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  • 301. Sun, Shiguo
    et al.
    Yang, Yang
    Liu, Fengyu
    Pang, Yi
    Fan, Jiangli
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Peng, Xiaojun
    Study of Highly Efficient Bimetallic Ruthenium Tris-bipyridyl ECL Labels for Coreactant System2009Inngår i: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 81, nr 24, s. 10227-10231Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of bimetallic ruthenium complexes [(bpy)(2)Ru(bpy)(CH2)(n)(bpy)Ru(bpy)(2)](4+) (1, where bpy is 2,2'-bipyridinyl, n = 3, 5, 8) for the coreactant electrochemiluminescence (ECL) system have been synthesized. Their ECL property at different working electrode has been studied in 0.1 M phosphate buffer by using tripropylamine (TPrA) and 2-(dibutylamino) ethanol (DBAE) as the coreactant. The results demonstrate that the ECL intensity depends largely on the length of the saturated carbon chain linkage: the longer is the carbon chain, the higher is the ECL intensity. A remarkable ECL enhancement (up to about 25 times), in comparison with the commonly used metallic [Ru(bpy)(3)](2+), has been observed from 1c (n = 8) at Pt electrode. With 20 mM TPrA, the log of the ECL intensity increases linearly with the log of complex 1c concentrations over the concentration range of 1.0 x 10(-16) to 1.0 x 10(-6) M at glassy carbon electrode. The detection limit is 1.0 x 10(-16) M at a signal-to-noise ratio of 3. This is the highest ECL detection limit for bimetallic system reported until now. The study provides a general methodology to further improve and tune the ECL efficiency by using multimetallic ruthenium complexes.

  • 302.
    Sun, Shiguo
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhang, Rong
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Andersson, Samir
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Pan, Jingxi
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Akermark, Bjorn
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    The photoinduced long-lived charge-separated state of Ru(bPY)(3)-methylviologen with cucurbit 8 uril in aqueous solution2006Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 40, s. 4195-4197Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A stable 1 : 1 inclusion complex of Ru(bpy)(3)-MV2+ with cucurbit[8]uril (CB[8]) is formed in aqueous solution; upon light irradiation, a long lived (tau similar to 2 mu s) charge-separated state Ru3+- MV+.-CB[8] is observed.

  • 303.
    Sun, Shiguo
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhang, Rong
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Andersson, Samir
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Pan, Jingxi
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Zou, Dapeng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Åkermark, Björn
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Host-guest chemistry and light driven molecular lock of Ru(bpy)(3)-viologen with cucurbit 7-8 urils2007Inngår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 111, nr 47, s. 13357-13363Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Host-guest chemistry and photoinduced electron-transfer processes have been studied in the systems containing Ru(bPy)(3) complex covalently linked to viologen as a guest molecule and cucurbit[n]urils (n = 7, 8) as host molecules in aqueous solution. The Ru(bpy)(3)-viologen complex,[Ru(2,2 '-bipyridine)(2)(4-(4-(1 '-methyl-4,4 '-bipyridinediium-1-yl)butyl)-4 '-methyl-2,2 '-bipyridine)]Cl-4(denoted as RU2+-MV2+, 1) was shown to form stable 1:1 inclusion complexes with cucurbit[7]uril (CB[7]) and cucurbit[8] uril (CB[8]). The binding modes are slightly different with CB[7] and CB[8]. CB[7] preferentially binds to part of the viologen residue in 1 together with the butyl chain, whereas CB[8] preferentially encloses the whole viologen residue. Photoinduced intramolecular electron transfer from the excited-state of the Ru moiety to MV2+ which is inserted into the cavity of the CBs occurred. Long-lived charge-separated states RU3+-MV+center dot, were generated with the lifetimes of 280 ns with CB[7] and 2060 ns with CB[8]. This shows that CBs can slow down the charge recombination within supramolecular systems, and the difference in lifetimes seems to be due to the difference in binding modes. In the presence of a sacrificial electron donor triethanolarnine, light-driven formation of a dimer of MV+center dot inside the CB[8] cavity was observed. This locked molecular dimer can be unlocked by molecular oxygen to give back the original form of the molecular dyad 1 with the MV2+ moiety inserted in the cavity of CB[8]. The processes could be repeated several times and showed nice reversibility.

  • 304. Tan, Qin
    et al.
    Yang, Xichuan
    Cheng, Ming
    Wang, Haoxin
    Wang, Xiuna
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. State Key Laboratory of Fine Chemicals, Dalian, China .
    Application of Small Molecule Donor Materials Based on Phenothiazine Core Unit in Bulk Heterojunction Solar Cells2014Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 118, nr 30, s. 16851-16855Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A D-pi-A type small molecule PTZ1 and an A-pi-D-pi-A type small molecule PTZ2 with phenothiazine as the central building block and dicyanovinyl as the electron-withdrawing end-group have been designed and synthesized. Compared with D-pi-A type donor material PTZ1, the donor material PTZ2 with A-pi-D-pi-A configuration shows much wider response to solar light. The donor material PTZ1 possesses more positive highest occupied molecular orbital level, and higher V obtained for devices with PTZ1/PC71BM blend as the active layer. An improved efficiency of 3.25% was obtained for the PTZ2/PC71BM based solar cells.

  • 305. Teng, Chao
    et al.
    Yang, Xichuan
    Li, Shifeng
    Cheng, Ming
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Wu, Li-Zhu
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Tuning the HOMO Energy Levels of Organic Dyes for Dye-Sensitized Solar Cells Based on Br(-)/Br(3)(-) Electrolytes2010Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, nr 44, s. 13127-13138Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of novel metal free organic dyes TC301-TC310 with relatively high HOMO levels were synthesized and applied in dye sensitized solar cells (DSCs) based on electrolytes that contain Br(-)/Br(3)- and I(-)/I(3)(-) The effects of additive Li(+) ions and the HOMO levels of the dyes have an important influence on properties of the dyes and performance of DSCs The addition of Li(+) ions in electrolytes can broaden the absorption spectra of the dyes on TiO(2) films and shift both the LUMO levels of the dyes and the conduction band of TiO(2) thus leading to the increase of J(sc) and the decrease of V(oc) Upon using Br(-)/Br(3)(-) instead of I(-)/I(3)(-), a large increase of V(oc) is attributed to the enlarged energy difference between the redox potentials of electrolyte and the Fermi level of TiO(2), as well as the suppressed electron recombination Incident photon to current efficiency (IPCE) action spectra, electrochemical impedance spectra, and nanosecond laser transient absorption reveal that both the electron collection yields and the dye regeneration yields ((sic)(r)) depend on the potential difference (the driving forces) between the oxidized dyes and the Br(-)/Br(3)(-) redox couple For the dyes for which the HOMO levels are more positive than the redox potential of Br(-)/Br(3)(-) sufficient driving forces lead to the longer effective electron diffusion lengths and almost the same efficient dye regenerations, whereas for the dyes for which the HOMO levels are similar to the redox potential of Br(-)/Br(3)(-), insufficient driving forces lead to shorter effective electron-diffusion lengths and inefficient dye regenerations

  • 306. Teng, Chao
    et al.
    Yang, Xichuan
    Yang, Chao
    Li, Shifeng
    Cheng, Ming
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemivetenskap (CHE), Kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Molecular Design of Anthracene-Bridged Metal-Free Organic Dyes for Efficient Dye-Sensitized Solar Cells2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 19, s. 9101-9110Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of metal-free organic dyes bridged by anthracene-containing pi-conjugations were designed and synthesized as new chromophores for the application of dye-sensitized solar cells (DSCs). Detailed investigations on the relationship between the dye structures, photophysical properties, electrochemical properties, and performances of DSCs are described. With the introduction of the anthracene moiety, together with a triple bond for the fine-tuning of molecular planar configurations and to broaden absorption spectra, the short-circuit photocurrent densities (J(sc)) and open-circuit photovoltages (V-oc) of DSCs were improved to a large extent. The improvement of J(sc) is attributed to much broader absorption spectra of the dyes with the anthracene moiety. Electrochemical impedance spectroscopy (EIS) analysis reveals that the introduction of the anthracene moiety suppresses the charge recombination arising from electrons in TiO2 films with I-3(-) ions in the electrolyte, thus improving V-oc considerably. On the basis of optimized molecular structures and DSC test conditions, the dye TC501 shows a prominent solar energy conversion efficiency (eta) up to 7.03% (J(sc) = 12.96 mA . cm(-2), V-OC = 720 mV, ff = 0.753) under simulated AM 1.5 irradiation (100 mW . cm(-2)).

  • 307. Teng, Chao
    et al.
    Yang, Xichuan
    Yang, Chao
    Tian, Haining
    Li, Shifeng
    Wang, Xiuna
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Influence of Triple Bonds as pi-Spacer Units in Metal-Free Organic Dyes for Dye-Sensitized Solar Cells2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 25, s. 11305-11313Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Four metal-free organic sensitizers (TC101-TC104) with triple bonds in pi-spacers and five reference dyes (TC, TC105, TPC1, D5, and TH208) without triple bonds were applied in dye-sensitized solar cells to study the influence of triple bonds as pi-spacer units on their photoelectrochemical properties and dye-sensitized solar cells (DSCs) performance. Results show that the introduction of triple bond could red-shift the dye's absorption spectrum due to the enhancement of the pi-spacer. However, the spectrum red-shift is much less than that of the introduction of double bond because of more electronegativity of triple bond. The incident photon-to-current conversion efficiency reveals that the electron transfer yield (Phi(nu)(ET)) of DSCs becomes larger with the introduction of triple bond. Electrochemical impedance spectroscopy analysis reveals that the introduction of triple bond almost does not change the electron lifetimes in TiO2 films but decreases the effective diffusion lengths.

  • 308. Teng, Chao
    et al.
    Yang, Xichuan
    Yuan, Chunze
    Li, Chaoyan
    Chen, Ruikui
    Tian, Haining
    Li, Shifeng
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Two Novel Carbazole Dyes for Dye-Sensitized Solar Cells with Open-Circuit Voltages up to 1 V Based on Br-/Br-3(-) Electrolytes2009Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 11, nr 23, s. 5542-5545Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dye-sensitized solar cells (DSCs) based on two novel carbazole dyes (TC301 and TC306) and a Br-/Br-3(-) redox mediator in dried CH3CN solutions as electrolytes yielded a V-oc of 1.156 V and a eta value of 3.68% and a V-oc of 0.939 V and a eta value of 5.22% under simulated AM 1.5, respectively. The dyes TC301 and TC306 have more positive HOMO levels (1.59 and 1.38 V vs NHE) than the redox potential of Br-/Br-3(-)-based electrolytes, which have sufficient driving force to regenerate dyes. Under similar conditions with an I-/I-3(-) instead of a Br-/Br-3(-) redox mediator, DSCs sensitized by the dyes TC301 and TC306 produced a V-oc of 0.696 V and a eta value of 2.36% and a V-oc of 0.621 V and a eta value of 4.10%, respectively.

  • 309.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Bora, Ilkay
    KTH, Skolan för kemivetenskap (CHE), Kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Jiang, Xiao
    Gabrielsson, Erik
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Karlsson, Karl Martin
    KTH, Skolan för kemivetenskap (CHE), Kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Modifying organic phenoxazine dyes for efficient dye-sensitized solar cells2011Inngår i: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 21, nr 33, s. 12462-12472Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Four organic dyes bearing the phenoxazine chromophore have been synthesized and applied in dye-sensitized solar cells (DSCs). The effect of different dye structures on the performance of the DSCs was investigated systematically with photophysical, photovoltaic as well as photoelectrochemical methods. Due to the slow recombination process between injected electrons and electrolyte, the IB3 dye with two 2,4-dibutoxyphenyl units showed the best efficiency of 7.0% under 100 mW cm(-2) light illumination in the liquid state-DSCs. Moreover, the phenoxazine dyes-based solid state-DSCs were fabricated for the first time. With the IB4 dye, a higher efficiency of 3.2% has been achieved under the same light intensity.

  • 310.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Gabrielsson, Erik
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lohse, Peter William
    Vlachopoulos, Nick
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Hagfeldt, Anders
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Development of an organic redox couple and organic dyes for aqueous dye-sensitized solar cells2012Inngår i: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 5, nr 12, s. 9752-9755Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A water-soluble organic redox couple (TT-/DTT) and new organic dyes (D45 and D51) have been developed for aqueous dye-sensitized solar cells (DSCs). An optimal efficiency of 3.5% was obtained using the D51 dye and an optimized electrolyte composition. The highest IPCE value obtained was 68% at 460 nm.

  • 311.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Gabrielsson, Erik
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Yu, Ze
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    A thiolate/disulfide ionic liquid electrolyte for organic dye-sensitized solar cells based on Pt-free counter electrodes2011Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 47, nr 36, s. 10124-10126Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ionic liquid, 1-ethyl-3-methylimidazolium tetracyanoborate, was employed to prepare a thiolate/disulfide ionic liquid electrolyte with low viscosity for organic dye-sensitized solar cells (DSCs). CoS was introduced and showed better photovoltaic performance in DSCs than the ubiquitous platinized FTO CE.

  • 312.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Jiang, Xiao
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Yu, Ze
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi (stängd 20110630).
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi (stängd 20110630).
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Efficient Organic-Dye-Sensitized Solar Cells Based on an Iodine-Free Electrolyte2010Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 49, nr 40, s. 7328-7331Artikkel i tidsskrift (Fagfellevurdert)
  • 313.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Oscarsson, Johan
    Gabrielsson, Erik
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Eriksson, Susanna K.
    Lindblad, Rebecka
    Xu, Bo
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Hao, Yan
    Boschloo, Gerrit
    Johansson, Erik M. J.
    Gardner, James M.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Hagfeldt, Anders
    Rensmo, Håkan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Enhancement of p-Type Dye-Sensitized Solar Cell Performance by Supramolecular Assembly of Electron Donor and Acceptor2014Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 4, s. 4282-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Supramolecular interactions based on porphyrin and fullerene derivatives were successfully adopted to improve the photovoltaic performance of p-type dye-sensitized solar cells (DSCs). Photoelectron spectroscopy (PES) measurements suggest a change in binding configuration of ZnTCPP after co-sensitization with C60PPy, which could be ascribed to supramolecular interaction between ZnTCPP and C60PPy. The performance of the ZnTCPP/C60PPy-based p-type DSC has been increased by a factor of 4 in comparison with the DSC with the ZnTCPP alone. At 560 nm, the IPCE value of DSCs based on ZnTCPP/C60PPy was a factor of 10 greater than that generated by ZnTCPP-based DSCs. The influence of different electrolytes on charge extraction and electron lifetime was investigated and showed that the enhanced V-oc from the Co2+/(3+)(dtbp)(3)-based device is due to the positive E-F shift of NiO.

  • 314.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Soto, Andrea
    Xu, Bo
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Hagfeldt, Anders
    Fabregat-Santiago, Francisco
    Mora-Sero, Ivan
    Kang, Yong Soo
    Bisquert, Juan
    Barea, Eva M.
    Effect of the chromophores structures on the performance of solid-state dye sensitized solar cells2014Inngår i: Nano, ISSN 1793-2920, Vol. 9, nr 5, s. 1440005-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The er effect of metal-free chromophores on dye-sensitized solar cell performance is investigated. Solid state dye-sensitized solar cells (ssDSCs) using dirfferent molecular sensitizers based on tri-phenylamine (TPA) with thiophene linkers and different alkyl chain in the donor unit have been characterized using impedance spectroscopy (IS). We show that different molecular structures play a fundamental role on solar cell performance, by the effect produced on TiO2 conduction band position and in the recombination rate. Dye structure and its electronic properties are the main factors that control the recombination, the capacitance and the efficiency of the cells. A clear trend between the performance of the cell and the optimization level of the blocking effect of the dye structure has been identified in the solid state solar cells with Spiro-OMeTAD hole conductor.

  • 315.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Iodine-free redox couples for dye-sensitized solar cells2011Inngår i: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 21, nr 29, s. 10592-10601Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Redox couples, as one of the crucial components of dye-sensitized solar cells, have been investigated for many years. Due to the many drawbacks of I I(-)/I(3)(-) electrolyte, scientists have paid more attention to seeking other alternative electrolyte systems. Up to now, the best efficiency of iodine-free redox couple-based DSCs, 7.5%, has been achieved by ferrocene/ferrocenium redox couple under AM 1.5G, 100mW cm(-2) light illumination and other redox couples also show the promising future in DSCs. In this feature article, we systematically present three series of iodine-free redox couples including metal-complexes, inorganic and pure organic redox couples, and further compare the different photovoltaic and photophysical properties of these redox couples. As a consequence, the goals of this article are to show the important progress achieved in the redox couples research area of DSCs and analyze the advantages as well as the disadvantages of these redox couples to speed up the further development of iodine-free redox couples in the future.

  • 316. Tian, Haining
    et al.
    Yang, Xichuan
    Chen, Ruikui
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    A metal-free "black dye'' for panchromatic dye-sensitized solar cells2009Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A novel metal-free "black dye'' was designed and synthesized for panchromatic dye-sensitized solar cells. Based on this dye, the broader incident photon-to-current conversion efficiency spectrum was obtained over the whole visible range extending into the near-IR region up to 920 nm.

  • 317. Tian, Haining
    et al.
    Yang, Xichuan
    Chen, Ruikui
    Pan, Yuzhen
    Li, Lin
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Phenothiazine derivatives for efficient organic dye-sensitized solar cells2007Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 36, s. 3741-3743Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Novel organic dyes based on the phenothiazine (PTZ) chromophore were designed and synthesized for dye-sensitized solar cells, which give solar energy-to-electricity conversion efficiency (eta) of up to 5.5% in comparison with the reference Ru-complex (N3 dye) with an eta value of 6.2% under similar experimental conditions.

  • 318. Tian, Haining
    et al.
    Yang, Xichuan
    Cong, Jiayan
    Chen, Ruikui
    Liu, Jing
    Hao, Yan
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi (stängd 20110630). KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. Dalian Univ Technol, China.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. Dalian Univ Technol, China.
    Tuning of phenoxazine chromophores for efficient organic dye-sensitized solar cells2009Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 41, s. 6288-6290Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Through introducing an energy antenna system into a simple phenoxazine dye (TH301), a novel and efficient dye TH305 was designed and synthesized for application in a dye sensitized solar cell with prominent overall conversion efficiency of 7.7%.

  • 319. Tian, Haining
    et al.
    Yang, Xichuan
    Cong, Jiayan
    Chen, Ruikui
    Teng, Chao
    Liu, Jing
    Hao, Yan
    Wang, Lei
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Effect of different electron donating groups on the performance of dye-sensitized solar cells2010Inngår i: Dyes and pigments, ISSN 0143-7208, E-ISSN 1873-3743, Vol. 84, nr 1, s. 62-68Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of organic sensitizers containing identical pi-spacers and electron acceptors but different, aromatic amine electron-donating groups, were used in dye-sensitized solar cells to study the effect of the electron donating groups on device performance. The derived photophysical and photovoltaic properties, as well as density functional theory calculations, revealed that the tetrahydroquinoline dye was prone to aggregate upon the surface of titanium dioxide owing to the dye's planar structure. A 45% improvement in efficiency of a tetrahydroquinoline dye based cell was achieved when chenodeoxycholic acid was employed as co-adsorbent. However, the airscrew type of triphenylamine unit and Y type structure of the substituted phenothiazine framework suppressed dye aggregation on titanium dioxide. The efficiency of a phenothiazine dye-based cell fabricated using saturated co-adsorbent in dichloromethane was only 15% greater than that achieved in the absence of co-adsorbent. Electrochemical Impedance Spectroscopy was used to determine the interfacial charge transfer process occurring in solar cells that employed different dyes in both the absence and presence of chenodeoxycholic acid as co-adsorbent.

  • 320. Tian, Haining
    et al.
    Yang, Xichuan
    Pan, Jingxi
    Chen, Ruikui
    Liu, Ming
    Zhang, Qingyu
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    A Triphenylamine Dye Model for the Study of Intramolecular Energy Transfer and Charge Transfer in Dye-Sensitized Solar Cells2008Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 18, nr 21, s. 3461-3468Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A novel dye (2TPA-R), containing two triphenylamine (TPA) units connected by a vinyl group and rhodanine-3-acetic acid as the electron acceptor, is designed and synthesized successfully to reveal the working principles of organic dye in dye-sensitized solar cells (DSSCs). 2TPA and TPA-R, which consist of two TPA units connected by vinyl and a TPA unit linked with rhodanine-3-acetic acid, respectively, are also synthesized as references to study the intramolecular energy transfer (EnT) and charge transfer (ICT) processes of 2TPA-R in CH2Cl2 solution and on a TiO2 surface. The results suggest that the intramolecular EnT and ICT processes show a positive effect on the performance of DSSCs. However, the flexible structure and less-adsorbed amount of dye on TiO2 may make it difficult to improve the efficiency of DSSCs. This study on intramolecular EnT and ICT processes acts as a guide for the design and synthesis of efficient organic dyes in the future.

  • 321.
    Tian, Haining
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Yu, Ze
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi (stängd 20110630).
    Hagfeldt, Anders
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi (stängd 20110630).
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Organic Redox Couples and Organic Counter Electrode for Efficient Organic Dye-Sensitized Solar Cells2011Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 133, nr 24, s. 9413-9422Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of organic thiolate/disulfide redox couples have been synthesized and have been studied systematically in dye-sensitized solar cells (DSCs) on the basis of an organic dye (TH305). Photophysical, photoelectrochemical, and photovoltaic measurements were performed in order to get insights into the effects of different redox couples on the performance of DSCs. The polymeric, organic poly(3,4-ethylenedioxythiophene) (PEDOT) material has also been introduced as counter electrode in this kind of noniodine-containing DSCs showing a promising conversion efficiency of 6.0% under AM 1.5G, 100 mW.cm(-2) light illumination. Detailed studies using electrochemical impedance spectroscopy and linear-sweep voltammetry reveal that the reduction of disulfide species is more efficient on the PEDOT counter electrode surface than on the commonly used platinized conducting glass electrode. Both pure and solvated ionic-liquid electrolytes based on a thiolate anion have been studied in the DSCs. The pure and solvated ionic-liquid-based electrolytes containing an organic redox couple render efficiencies of 3.4% and 1.2% under 10 mW.cm(-2) light illumination, respectively.

  • 322. Tian, Jie
    et al.
    Yang, Xichuan
    Zhao, Jianghua
    Wang, Lei
    Wang, Weihan
    Li, Jiajia
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian Univ Technol, Peoples R China.
    Organic D-pi-A sensitizer with pyridinium as the acceptor group for dye-sensitized solar cells2014Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 4, nr 65, s. 34644-34648Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two metal-free organic dyes with triphenylamide (TPA) as the donor group and pyridinium (m-carboxyl-N-methylpyridinium and N-methylcarboxylpyridinium) as the acceptor and anchoring group have been synthesized for dye-sensitized solar cells (DSSCs). A systematic investigation of the relationship between the structures and physical, electrochemical and photovoltaic properties has been conducted. The devices sensitized by TJ101 which employed m-carboxyl-N-methylpyridinium as the acceptor group has achieved a conversion efficiency of 5.4% (J(sc) = 10.8 mA cm(-2), V-oc = 680 mV, FF = 74.2%) under AM 1.5 irradiation. In contrast, much lower efficiency of 4.0% was obtained when a reference dye TJ101R with m-carboxylpyridine as the acceptor group was employed as a sensitizer.

  • 323.
    Tong, Lianpeng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Xu, Yunhua
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Privalov, Timofei
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Structural Modifications of Mononuclear Ruthenium Complexes: A Combined Experimental and Theoretical Study on the Kinetics of Ruthenium-Catalyzed Water Oxidation2011Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 50, nr 2, s. 445-449Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Small change, big difference: A minor structural modification of water-oxidation catalysts changes the kinetics of O2 evolution from second- to first-order (see scheme). According to DFT calculations, the torsional flexibility of the chelating ligands and their reorganization through the catalytic cycle are implicated in pathway selectivity, and the auxiliary carboxylate group becomes involved in proton-coupled nucleophilic attack.

  • 324.
    Tong, Lianpeng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Götelid, Mats
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och tillämpad fysik, MAP.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Oxygen evolution at functionalized carbon surfaces: A strategy for immobilization of molecular water oxidation catalysts2012Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 48, nr 80, s. 10025-10027Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A molecular Ru(ii) water oxidation catalyst was immobilized on a conductive carbon surface through a covalent bond, and its activity was maintained at the same time. The method can be applied to other materials and may inspire development of artificial photosynthesis devices.

  • 325.
    Tong, Lianpeng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Inge, A. Ken
    Stockholm University.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Wang, Lei
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zou, Xiaodong
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Catalytic Water Oxidation by Mononuclear Ru Complexes with an Anionic Ancillary Ligand2013Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 52, nr 5, s. 2505-2518Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mononuclear Ru-based water oxidation catalysts containing anionic ancillary ligands have shown promising catalytic efficiency and intriguing properties. However, their insolubility in water restricts a detailed mechanism investigation. In order to overcome this disadvantage, complexes [Ru-II(bpc)(bpy)OH2](+) (1(+), bpc = 2,2'-bipyridine-6-carboxylate, bpy = 2,2'-bipyridine) and [Ru-II(bpc)(pic)(3)](+) (2(+), pic = 4-picoline) were prepared and fully characterized, which features an anionic tridentate ligand and has enough solubility for spectroscopic study in water. Using Ce-IV as an electron acceptor, both complexes are able to catalyze O-2-evolving reaction with an impressive rate constant. On the basis of the electrochemical and kinetic studies, a water nucleophilic attack pathway was proposed as the dominant catalytic cycle of the catalytic water oxidation by 1(+), within which several intermediates were detected by MS. Meanwhile, an auxiliary pathway that is related to the concentration of Ce-IV was also revealed. The effect of anionic ligand regarding catalytic water oxidation was discussed explicitly in comparison with previously reported mononuclear Ru catalysts carrying neutral tridentate ligands, for example, 2,2':6',2 ''-terpyridine (tpy). When 2(+) was oxidized to the trivalent state, one of its picoline ligands dissociated from the Ru center. The rate constant of picoline dissociation was evaluated from time-resolved UV-vis spectra.

  • 326.
    Tong, Lianpeng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Wang, Ying
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Xu, Yunhua
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Cheng, Xiao
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Fischer, Andreas
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Ahlquist, Mårten S. G.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Water Oxidation Catalysis: Influence of Anionic Ligands upon the Redox Properties and Catalytic Performance of Mononuclear Ruthenium Complexes2012Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 51, nr 6, s. 3388-3398Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Aiming at highly efficient molecular catalyts for water oxidation, a mononuclear ruthenium complex Ru-II(hqc)(pic)(3) (1; H(2)hqc = 8-hydroxyquinoline-2-carboxylic acid and plc = 4-picoline) containing negatively charged carboxylate and phenolate donor groups has been designed and synthesized. As a comparison, two reference complexes, Ru-II(pdc)(pic)(3) (2; H(2)pdc = 2,6-pyridine-dicarboxylic acid) and Ru-II(tpy)(pic)(3) (3; tpy = 2,2':6',2 ''-terpyridine), have also been prepared. All three complexes are fully characterized by NMR, mass spectrometry (MS), and X-ray crystallography. Complex 1 showed a high efficiency toward catalytic water oxidation either driven by chemical oxidant (Ce-IV in a pH 1 solution) with a initial turnover number of 0.32 s(-1), which is several orders of magnitude higher than that of related mononuclear ruthenium catalysts reported in the literature, or driven by visible light in a three-component system with [Ru(bpy)(3)](2+) types of photosensitizers. Electrospray ionization MS results revealed that at the Rum state complex 1 undergoes ligand exchange of 4-picoline with water, forming the authentic water oxidation catalyst in situ. Density functional theory (DFT) was ernployed to explain how anionic ligands (hqc and pdc) facilitate the 4-picoline dissociation compared with a neutral ligand (tpy). Electrochemical measurements show that complex 1 has a much lower E(Ru-III/Ru-II) than that of reference complex 2 because of the introduction of a phenolate ligand. DFT was further used to study the influence of anionic ligands upon the redox properties of mononuclear aquaruthenium species, which are postulated to be involved in the catalysis cycle of water oxidation.

  • 327. Tran, Lien-Hoa
    et al.
    Eriksson, Lars
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Akermark, Bjorn
    A new square planar mononuclear Mn-III complex for catalytic epoxidation of stilbene2008Inngår i: Journal of Organometallic Chemistry, ISSN 0022-328X, E-ISSN 1872-8561, Vol. 693, nr 6, s. 1150-1153Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The manganese(III) complex (2) with a diamide ligand has been synthesized. This complex was found to catalyze both the epoxidation of (Z)- and (E)-stilbene with high conversion and the oxidation of benzyl alcohol to benzaldehyde.

  • 328. Troppmann, Stefan
    et al.
    Brandes, Eva
    Motschmann, Hubert
    Li, Fei
    Wang, Mei
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian Univ Technol, China.
    Koenig, Burkhard
    Enhanced Photocatalytic Hydrogen Production by Adsorption of an [FeFe]-Hydrogenase Subunit Mimic on Self-Assembled Membranes2016Inngår i: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, nr 4, s. 554-560Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Self-assembled vesicles with membrane-embedded or adsorbed ruthenium polypyridine complexes were further functionalized by the adsorption of an [FeFe]-hydrogenase subunit mimic to the membrane interface enhancing the photocatalytic hydrogen production in water under acidic conditions. The resulting two-dimensional membrane assembly places the photosensitizer and hydrogen-evolving diiron complex in close proximity resulting in a six-to twelvefold increase in the turnover number as compared to the same system in the absence of lipid membranes. The interface assembly then enables the combining of hydrophilic and hydrophobic catalytic entities for light-driven proton reduction in acidic water and provides a flexible method for membrane functionalization.

  • 329. Wang, Dongping
    et al.
    Wang, Mei
    Wang, Xiuna
    Zhang, Rong
    Ma, Jia
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Influence of the built-in pyridinium salt on asymmetric epoxidation of substituted chromenes catalysed by chiral (pyrrolidine salen)Mn(III) complexes2007Inngår i: Journal of Molecular Catalysis A: Chemical, ISSN 1381-1169, E-ISSN 1873-314X, Vol. 270, nr 02-jan, s. 278-283Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Chiral (pyrrolidine salen)Mn(III) complexes 1 with an N-benzoyl group and 2 with an N-isonicotinoyl group as well as the corresponding N-methyl (3) and N-benzyl (4) pyridinium salts of 2 were synthesized. The catalytic properties of 1-4 and 2 with excess CH3I were explored to figure out the influence of the internal pyridinium salt in the catalyst on asymmetric epoxidation of substituted chromenes with NaClO/PPNO as an oxidant system in the aqueous/organic biphasic medium. The (pyrrolidine salen)Mn(III) complexes with an internal pyridinium salt, either formed in situ or isolated, displayed higher activities than analogous complexes 1, 2 and Jacobsen's catalyst in the aforementioned reaction, with comparable high yields and ee values. The acceleration of the reaction rate is attributed to the phase transfer capability of the built-in pyridinium salt of the (salen)Mn(III) catalyst. The effect of the internal pyridinium salt on the epoxidation of substituted chromenes is similar to that of the external pyridinium salts and ammonium halides.

  • 330. Wang, Dongping
    et al.
    Wang, Mei
    Zhang, Rong
    Wang, Xiuna
    Gao, Aiping
    Ma, Jia
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Asymmetric epoxidation of styrene and chromenes catalysed by dimeric chiral (pyrrolidine salen)Mn(III) complexes2006Inngår i: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 315, s. 120-127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two dimeric chiral (pyrrolidine salen)Mn(III) complexes 3 and 4 were prepared, in which the two (pyrrolidine salen)Mn(III) units are linked either by a p-xylylene or by ap-phthalyl bridge. High yields were attained for asymmetric epoxidation of styrene and substituted chromenes at 0.5-4.0 mol% catalyst loading of 3 and 4 using NaClO/PPNO and m-CPBA/NMO as oxidant systems, with 37-39% ee for styrene and 86-95% ee for substituted chromenes. Dimeric complexes 3 and 4 displayed higher activities than their parent monomeric complexes 1 and 2 of double equiv for epoxidation of substituted chromenes. Complex 3 bearing two tertiary amine units displayed considerably higher activity than analogous dimeric complex 4 containing two carboxamide units in the aforementioned reaction. The effect of excess CH3I on the epoxidation of 6-nitro-2,2-dimethylchromene catalysed by 3 in the aqueous/organic biphasic medium was explored. The recovery and recycling possibilities of the dimeric complexes 3 and 4 were studied.

  • 331. Wang, F. J.
    et al.
    Wang, M.
    Liu, X. Y.
    Jin, K.
    Dong, W. B.
    Li, G. H.
    Åkermark, B.
    Sun, Licheng C.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian University of Technology, China.
    Spectroscopic and crystallographic evidence for the N-protonated (FeFeI)-Fe-I azadithiolate complex related to the active site of Fe-only hydrogenases2005Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 25, s. 3221-3223Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The complex [{(mu-SCH2)(2)N(CH2C6H4-2-Br)}Fe-2(CO)(6)] and its N-protonated species, as structural models of the Fe-only hydrogenase active site, were identified spectroscopically and crystallographically, and their molecular structures show the 0.04 - 0.1 angstrom lengthening of the three N-C bonds and an intramolecular H center dot center dot center dot Br contact (2.82 angstrom) in the crystalline state of the N-protonated species.

  • 332. Wang, Fujun
    et al.
    Wang, Mei
    Liu, Xiaoyang
    Jin, Kun
    Donga, Weibing
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Protonation, electrochemical properties and molecular structures of halogen-functionalized diiron azadithiolate complexes related to the active site of iron-only hydrogenases2007Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, nr 34, s. 3812-3819Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diiron complexes [{( mu-SCH2) 2NCH(2)C(6)H(4)X}{Fe( CO)(2)L}(2)] ( L = CO, X = 2-Br, 1; 2-F, 2; 3-Br, 3; L = PMe3, X = 2-Br, 4) were prepared as biomimetic models of the iron-only hydrogenase active site. The N-protonated species [ 1( NH)]+ClO4-, [ 2( NH)]+ClO4- and the mu-hydride diiron complex [ 4( FeHFe)]+PF6- were obtained in the presence of proton acids and well characterized. The protonation process of 4 was studied by in-situ IR and NMR spectroscopy, which suggests the formation of the diprotonated species [ 4( NH)( FeHFe)](2+) in the presence of an excess of proton acid. The molecular structures of 1, [ 1( NH)]+ClO4-, 4 and [ 4( FeHFe)]+PF6- were determined by X-ray crystallography. The single-crystal X-ray analysis reveals that an intramolecular H center dot center dot center dot Br contact ( 2.82 angstrom) in the crystalline state of [ 1( NH)]+ClO4-. In the presence of 1-6 equiv of the stronger acid HOTf, complex 1 is readily protonated on the bridged-N atom and can electrochemically catalyze the proton reduction at a relatively mild potential ( ca. -1.0 V). Complex 4 is also electrocatalytic active at -1.4 V in the presence of HOTf with formation of the mu-hydride diiron species.

  • 333.
    Wang, Haoxin
    et al.
    DUT, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    Yu, Ze
    DUT, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    Lai, Jianbo
    DUT, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    Song, Xinkai
    DUT, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    Yang, Xichuan
    DUT, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Lab Photomol Sci, CH-1015 Lausanne, Switzerland..
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. DUT, Inst Energy Sci & TechnolROYAL SOC CHEMISTRY, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem,Inst Artificial Photosynt, Dalian 116024, Peoples R China..
    One plus one greater than two: high-performance inverted planar perovskite solar cells based on a composite CuI/CuSCN hole-transporting layer2018Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 43, s. 21435-21444Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The low-cost and stable inorganic p-type semiconductor copper(i) iodide (CuI) is a promising hole-transporting layer (HTL) material for inverted planar perovskite solar cells (PSCs). However, the power conversion efficiencies (PCEs) of inverted planar PSCs based on CuI HTLs reported so far are not satisfactory and far behind those of their organic counterparts. Herein, we demonstrate a simple but effective approach to improve the performance of inverted planar PSCs based on the CuI HTL through the incorporation of copper thiocyanate (CuSCN) into the CuI HTL. As compared to pristine CuI, the introduction of CuSCN significantly improves the quality of the film, resulting in a smooth and uniform film while maintaining relatively high electrical conductivity. As a consequence, the champion device based on the composite CuI/CuSCN HTL affords an impressive PCE of 18.76% under full sun illumination (100 mW cm(-2), AM 1.5G), which is substantially higher than the corresponding values of the respective devices containing pristine CuI (14.53%) and CuSCN (16.66%). This value is one of the highest efficiencies reported thus far for CuI- and CuSCN-based HTLs in PSCs. This work demonstrates the great potential of low-temperature solution-processed CuI/CuSCN composites as hole-selective layers for low-cost and efficient PSCs as well as other optoelectronic devices.

  • 334.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Chen, Hong
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Daniel, Quentin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Philippe, Bertrand
    Yang, Yi
    Rensmo, Hakan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian Univ Technol, Peoples R China.
    Promoting the Water Oxidation Catalysis by Synergistic Interactions between Ni(OH)(2) and Carbon Nanotubes2016Inngår i: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 6, nr 15, artikkel-id 1600516Artikkel i tidsskrift (Fagfellevurdert)
  • 335.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ambre, Ram B.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Quentin, Daniel
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Chen, Hong
    Sun, Junliang
    Das, Biswanath
    Thapper, Anders
    Uhlig, Jens
    Dinér, Peter
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian University of Technology (DUT), China.
    A Nickel (II) PY5 Complex as an Electrocatalyst for Water Oxidation2016Inngår i: Journal of Catalysis, ISSN 0021-9517, Vol. 335, s. 72-78Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A Ni-PY5 [PY5 = 2,6-bis(1,1-bis(2-pyridyl)ethyl)pyridine)] complex has been found to act as an electrocatalyst for oxidizing water to dioxygen in aqueous phosphate buffer solutions. The rate of water oxidation catalyzed by the Ni-PY5 is remarkably enhanced by the proton acceptor base HPO42−, with rate constant of 1820 M−1 s−1. Controlled potential bulk electrolysis with Ni-PY5 at pH 10.8 under an applied potential of 1.5 V vs. normal hydrogen electrode (NHE) resulted in dioxygen formation with a high faradaic efficiency over 90%. A detailed mechanistic study identifies the water nucleophilic attack pathway for water oxidation catalysis.

  • 336.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Stewart, Beverly
    Pu, Maoping
    Liu, Jianhui
    Privalov, Timofei
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Toward Controlling Water Oxidation Catalysis: Tunable Activity of Ruthenium Complexes with Axial Imidazole/DMSO Ligands2012Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 134, nr 45, s. 18868-18880Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Using the combinations of imidazole and dimethyl :sulfoxide (DMSO) as axial ligands and 2,2'-bipyridine-6,6'-dicarboxylate (bda) as the equatorial ligand, we have synthesized six novel ruthenium complexes with noticeably different activity as water oxidation catalysts (WOCs). In four C-s symmetric Ru-II(kappa(3)-bda)(DMSO)L-2 complexes L = imidazole (1), N-methylimidazole (2), 5-methylimidazole (3), and 5-bromo-N-methylimidazole (4). Additionally, in two C-2v symmetric Ru-II(kappa(4)-bda)L-2 complexes L = 5-nitroimidazole (5) and 5-bromo-N-methylimidazole (6), that is, fully equivalent axial imidazoles. A detailed characterization of all complexes and the mechanistic investigation of the catalytic water oxidation have been carried out with a number of experimental techniques, that is, kinetics, electrochemistry and high resolution mass spectrometry (HR-MS), and density functional theory (DFT) calculations. We have observed the in situ formation: of a Ru-II-complex with the accessible seventh coordination position. The measured catalytic activities and kinetics of complex 1-6 revealed details about an important structure activity relation: the connection between the nature of axial ligands in the combination and either the increase or decrease of the catalytic activity. In particular, an axial DMSO group substantially increases the turnover frequency of WOCs reported in article, with the ruthenium-complex having one axial 5-bromo-N-methylimidazole and one axial DMSO: (4), we have obtained a high initial turnover frequency of similar to 180 s(-1). DFT modeling Of the binuclear reaction pathway of the O-O bond formation in catalytic Water oxidation further corroborated the concept of the mechanistic significance of the axial ligands and rationalized the experimentally observed difference in the activity of complexes with imidazole/DMSO and imidazole/imidazole combinations of axial ligands.

  • 337.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Tong, Lianpeng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Visible light-driven water oxidation catalyzed by mononuclear ruthenium complexes2013Inngår i: Journal of Catalysis, ISSN 0021-9517, E-ISSN 1090-2694, Vol. 306, s. 129-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of mononuclear ruthenium water oxidation catalysts (WOCs) [Ru(bda)L-2] (H(2)bda = 2,2'-bipyridine-6,6'-dicarboxylic acid; L = N-cyclic aromatic ligands) were investigated in three-component light-driven water oxidation systems composed of photosensitizers, a sacrificial electron acceptor, and WOCs. A high turnover number of 579 for water oxidation was achieved in the homogeneous system using complex 4 ([Ru(bda)(4-Br-pyridine)(2)]) as the WOC, and a high quantum efficiency of 17% was found which is a new record for visible light-driven water oxidation in homogeneous systems.

  • 338.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Wang, Ying
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Ahlquist, Mårten
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. State Key Lab of Fine Chemicals, DUT-KTH Joint Education and Research Center on Molecular Devices, Dalian University of Technology (DUT)Dalian, China .
    Highly efficient and robust molecular water oxidation catalysts based on ruthenium complexes2014Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 50, nr 85, s. 12947-12950Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two monomeric ruthenium molecular catalysts for water oxidation have been prepared, and both of them show high activities in pH 1.0 aqueous solutions, with an initial rate of over 1000 turnover s(-1) by complex 1, and a turnover number of more than 100 000 by complex 2.

  • 339.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fan, Ke
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Chen, Hong
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Daniel, Quentin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Philippe, Bertrand
    Rensmo, Håkan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Towards efficient and robust anodes for water splitting: Immobilization of Ru catalysts on carbon electrode and hematite by in situ polymerization2017Inngår i: Catalysis Today, ISSN 0920-5861, E-ISSN 1873-4308, Vol. 290, s. 73-77Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ru-bda based molecular water oxidation catalysts 1 and 2 (H(2)bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) containing a thiophene group are attached to the surfaces of electrodes by the method of electropolymerization. The Ru-bda molecular catalyst functionalized graphite carbon electrode can catalyze water oxidation efficiently under a overpotential of ca 500 mV to obtain current density of 5 mA cm(-2); and the similarly functionalized photoelectrode based on alpha-Fe2O3 (hematite) film can work as an photoanode for light driven water splitting.

  • 340.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fan, Ke
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Chen, Hong
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Towards Water Splitting Device: Functionalizing Electrodes with Ru catalyst by in situPolymerizationManuskript (preprint) (Annet vitenskapelig)
  • 341.
    Wang, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fan, Ke
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Daniel, Quentin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Li, Fusheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Philippe, B.
    Rensmo, H.
    Chen, H.
    Sun, J.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Electrochemical driven water oxidation by molecular catalysts in situ polymerized on the surface of graphite carbon electrode2015Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 51, nr 37, s. 7883-7886Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A simple strategy to immobilize highly efficient ruthenium based molecular water-oxidation catalysts on the basal-plane pyrolytic graphite electrode (BPG) by polymerization has been demonstrated. The electrode 1@BPG has obtained a high initial turnover frequency (TOF) of 10.47 s-1 at ∼700 mV overpotential, and a high turnover number (TON) up to 31600 in 1 h electrolysis.

  • 342. Wang, Lei
    et al.
    Mirmohades, Mohammad
    Brown, Allison
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Li, Fusheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Quentin, Daniel
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lomoth, Reiner
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China.
    Hammarstrom, Leif
    Sensitizer-Catalyst Assemblies for Water Oxidation2015Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 54, nr 6, s. 2742-2751Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two molecular assemblies with one Ru(II)-polypyridine photosensitizer covalently linked to one Ru(II)(bda)L2 catalyst (1) (bda = 2,2'-bipyridine-6,6'-dicarboxylate) and two photosensitizers covalently linked to one catalyst (2) have been prepared using a simple C-C bond as the linkage. In the presence of sodium persulfate as a sacrificial electron acceptor, both of them show high activity for catalytic water oxidation driven by visible light, with a turnover number up to 200 for 2. The linked photocatalysts show a lower initial yield for light driven oxygen evolution but a much better photostability compared to the three component system with separate sensitizer, catalyst and acceptor, leading to a much greater turnover number. Photocatalytic experiments and time-resolved spectroscopy were carried out to probe the mechanism of this catalysis. The linked catalyst in its Ru(II) state rapidly quenches the sensitizer, predominantly by energy transfer. However, a higher stability under photocatalytic condition is shown for the linked sensitizer compared to the three component system, which is attributed to kinetic stabilization by rapid photosensitizer regeneration. Strategies for employment of the sensitizer-catalyst molecules in more efficient photocatalytic systems are discussed.

  • 343. Wang, Lei
    et al.
    Yang, Xichuan
    Wang, Xiuna
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Novel organic dyes with anchoring group of quinoxaline-2, 3-diol and the application in dye-sensitized solar cells2015Inngår i: Dyes and pigments, ISSN 0143-7208, E-ISSN 1873-3743, Vol. 113, s. 581-587Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two organic quinoxaline dyes (WQ-1 and WQ-2) with a structure of quinoxaline-2, 3-diol as the electron withdrawing and anchoring group were synthesized and applied in the dye-sensitized solar cells. Fourier transform infrared spectroscopy and two other reference dyes (WQ-R1 and WQ-R2) without the hydroxyl groups were introduced to ascertain the adsorption properties of the dye series. The effect of the new electron acceptor and anchoring group on the performance of solar cells was investigated systematically. Under the standard light illumination (100 mW m(-2)), WQ-2 got an efficiency of 2.25%, with a short circuit photocurrent density of 5.51 mA cm(-2), an open circuit voltage of 0.612 V and a fill factor of 66.74%.

  • 344. Wang, Lei
    et al.
    Yang, Xichuan
    Zhao, Jianghua
    Zhang, Fuguo
    Wang, Xiuna
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Efficient Organic Sensitizers with Pyridine-N-oxide as an Anchor Group for Dye-Sensitized Solar Cells2014Inngår i: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 7, nr 9, s. 2640-2646Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Five organic dyes with pyridine-N-oxide as the anchor group and electron acceptor have been synthesized and applied in dye-sensitized solar cells (DSSCs). Benzothiadiazole was introduced in the conjugation system to increase the electron withdrawing properties, FTIR spectra showed that the coordination was between the pyridine-N-oxide and the Bronsted acid site on the TiO2 surface. The relationship between different dye structures and the performance of the DSSCs was investigated systematically. The location of the thiophene unit was studied, and the direct linkage of benzothiadiazole with pyridine-Noxide was beneficial to broaden the absorption. The donor-acceptor-acceptor-configured dye WL307, which has 2-ethylhexyloxy chains in the donor part, showed the best efficiency of 6.08% under 100 mWcm(-2) light illumination. The dye series showed a fairly good stability during the one month test period.

  • 345.
    Wang, Linqin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Sheibani, Esmaeil
    Guo, Yu
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Zhang, Wei
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Li, Yuanyuan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Liu, Peng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Xu, Bo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Kloo, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. Dalian Univ Technol, State Key Lab Fine Chem, Inst Artificial Photosynth, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China.
    Impact of Linking Topology on the Properties of Carbazole-Based Hole-Transport Materials and their Application in Solid-State Mesoscopic Solar Cells2019Inngår i: SOLAR RRL, ISSN 2367-198X, artikkel-id 1900196Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Carbazole is a promising core for the molecular design of hole-transport materials (HTMs) for solid-state mesoscopic solar cells (ssMSCs), such as solid-state dye-sensitized solar cells (ssDSSCs) and perovskite solar cells (PSCs) due to its low cost and excellent optoelectronic properties of its derivatives. Although carbazole-based HTMs are intensely investigated in ssMSCs and promising device performance is demonstrated, the fundamental understanding of the impact of linking topology on the properties of carbazole-based HTMs is lacking. Herein, the effect of the linking topology on the optical and electronic properties of a series of carbazole-based HTMs with 2,7-substitution and 3,6-substitution is systematically investigated. The results demonstrate that the 2,7-substituted carbazole-based HTMs display higher hole mobility and conductivity among this series of analogous molecules, thereby exhibiting better device performance. In addition, the conductivity of the HTMs is improved after light treatment, which explains the commonly observed light-soaking phenomenon of ssMSCs in general. All these carbazole-based HTMs are successfully applied in ssMSCs and one of the HTMs X50-based devices yield a promising efficiency of 6.8% and 19.2% in ssDSSCs and PSCs, respectively. This study provides guidance for the molecular design of effective carbazole-based HTMs for high-performance ssMSCs and related electronic devices.

  • 346.
    Wang, Linqin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. KTH Royal Inst Technol, Dept Chem, Organ Chem, SE-10044 Stockholm, Sweden..
    Zhang, Jinbao
    Monash Univ, Dept Mat Sci & Engn, 22 Alliance Lane, Clayton, Vic 3800, Australia..
    Liu, Peng
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad materialfysik. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH Royal Inst Technol, Dept Chem, Ctr Mol Devices, Appl Phys Chem, SE-10044 Stockholm, Sweden..
    Xu, Bo
    Uppsala Univ, Dept Chem, Angstrom Lab, Box 523, S-75120 Uppsala, Sweden..
    Zhang, Biaobiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. KTH Royal Inst Technol, Dept Chem, Organ Chem, SE-10044 Stockholm, Sweden..
    Chen, Hong
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. KTH Royal Inst Technol, Dept Chem, Organ Chem, SE-10044 Stockholm, Sweden..
    Inge, A. Ken
    Stockholm Univ, Dept Mat & Environm Chem MMK, SE-10691 Stockholm, Sweden..
    Li, Yuanyuan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH Royal Inst Technol, Dept Fibre & Polymer Technol, Wallenberg Wood Sci Ctr, SE-10044 Stockholm, Sweden..
    Wang, Haoxin
    Dalian Univ Technol, Inst Artificial Photosynth, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Cheng, Yi-Bing
    Monash Univ, Dept Mat Sci & Engn, 22 Alliance Lane, Clayton, Vic 3800, Australia..
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH Royal Inst Technol, Dept Chem, Ctr Mol Devices, Appl Phys Chem, SE-10044 Stockholm, Sweden..
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. KTH Royal Inst Technol, Dept Chem, Organ Chem, SE-10044 Stockholm, Sweden.;Dalian Univ Technol, Inst Artificial Photosynth, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Design and synthesis of dopant-free organic hole-transport materials for perovskite solar cells2018Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, nr 69Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two novel dopant-free hole-transport materials (HTMs) with spiro[dibenzo[c,h]xanthene-7,9-fluorene] (SDBXF) skeletons were prepared via facile synthesis routes. A power conversion efficiency of 15.9% in perovskite solar cells is attained by using one HTM without dopants, which is much higher than undoped Spiro-OMeTAD-based devices (10.8%). The crystal structures of both new HTMs were systematically investigated to reveal the reasons behind such differences in performance and to indicate the design principles of more advanced HTMs.

  • 347. Wang, M.
    et al.
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Photochemical Hydrogen Production with Earth-Abundant Metal Complexes as Molecular Catalysts2012Inngår i: Applied Homogeneous Catalysis with Organometallic Compounds: A Comprehensive Handbook in Three Volumes, Wiley Blackwell , 2012, s. 1655-1687Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 348. Wang, Mei
    et al.
    Chen, Lin
    Li, Xueqiang
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Approaches to efficient molecular catalyst systems for photochemical H(2) production using [FeFe]-hydrogenase active site mimics2011Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 40, nr 48, s. 12793-12800Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The research on structural and functional biomimics of the active site of [FeFe]-hydrogenases is in an attempt to elucidate the mechanisms of H(2)-evolution and uptake at the [FeFe]-hydrogenase active site, and to learn from Nature how to create highly efficient H(2)-production catalyst systems. Undoubtedly, it is a challenging, arduous, and long-term work. In this perspective, the progresses in approaches to photochemical H(2) production using mimics of the [FeFe]-hydrogenase active site as catalysts in the last three years are reviewed, with emphasis on adjustment of the redox potentials and hydrophilicity of the [FeFe]-hydrogenase active site mimics to make them efficient catalysts for H(2) production. With gradually increasing understanding of the chemistry of the [FeFe]-hydrogenases and their mimics, more bio-inspired proton reduction catalysts with significantly improved efficiency of H(2) production will be realized in the future.

  • 349. Wang, Mei
    et al.
    Chen, Lin
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Recent progress in electrochemical hydrogen production with earth-abundant metal complexes as catalysts2012Inngår i: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 5, nr 5, s. 6763-6778Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This perspective article reviews the recent important progress in electrocatalytic hydrogen production catalyzed by earth-abundant metal complexes. The catalysts are divided into two categories depending on the media used in the hydrogen-evolving reactions, with an emphasis on the types of acids employed. The catalysts used in the first category, which work in organic solutions, include nickel and cobalt complexes with base-containing diphosphine ligands, cobaloximes, cobalt tetrapyridine complexs, and [NiFe]-and [FeFe]-hydrogenase mimics. Molybdenum and cobalt pentapyridine complexes, as well as the cobalt bis(iminopyridine) complex reported very recently, are the most important examples of catalysts used in the second category, which work in aqueous solutions. The advantages and disadvantages of the different types of catalysts are discussed and the hydrogen-evolving mechanisms for the well-studied catalysts are illustrated. In addition, several molecular catalyst-modified electrodes for hydrogen production are described.

  • 350. Wang, Mei
    et al.
    Han, Kai
    Zhang, Shuai
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian University of Technology (DUT), China.
    Integration of organometallic complexes with semiconductors and other nanomaterials for photocatalytic H-2 production2015Inngår i: Coordination chemistry reviews, ISSN 0010-8545, E-ISSN 1873-3840, Vol. 287, s. 1-14Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The development of energy-efficient, cost-effective and durable photocatalytic systems for water splitting is one of the scientific problems that must be solved before the successful transformation from a fossil fuel-based economy to a solar fuel-based economy can be realized. Conventional photocatalytic systems are generally divided into heterogeneous systems of semiconductors, usually modified by noble metals or inorganic cocatalysts, and homogeneous systems comprised of molecular catalysts and organic or organometallic chromophores. In recent years, some hybrid photocatalytic systems were reported to be highly active and robust for photoinduced H-2 production, indicating that the integration of semiconducting materials with proper molecular catalysts is an effective strategy for constructing efficient photocatalytic systems for water splitting. This review will focus on hybrid photocatalytic systems, developed in the past three years, in which proton reduction molecular catalysts incorporate either semiconducting materials or inorganic, metal-organic, and other polymeric nanomaterials for photochemical H-2 generation from water. In the last section of the review, problems existing in the current hybrid photocatalytic systems are discussed; future challenges and developments are envisaged.

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