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  • 251. Lu, Z.
    et al.
    Gao, Y.
    Chen, H.
    Liu, Z.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi. Dalian University of Technology (DUT), Dalian, China.
    Water oxidation catalyzed by a charge-neutral mononuclear ruthenium(III) complex2017Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 46, nr 4, s. 1304-1310Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new charge-neutral Ru(iii) complex RuL(pic)3 (1) (H3L = 3,6-di-tert-butyl-9H-carbazole-1,8-dicarboxylic acid, pic = 4-picoline) was synthesized and fully characterized. This complex promoted chemical and photochemical water oxidation efficiently with turnover frequencies of 0.28 s-1 and 5 min-1, respectively. In particular, for photochemical water oxidation, complex 1 showed excellent stability and good activity. The X-ray crystal structure, electrochemical results, and the detection of the RuIV-OH intermediate by high-resolution mass spectrometry revealed that complex 1 exchanged its 4-picoline ligand with water at the RuIII state to form the authentic water oxidation catalyst. The kinetics studies suggested a reaction mechanism involving nucleophilic attack by a water molecule.

  • 252. Lu, Zhongkai
    et al.
    Gao, Yan
    Chen, Hong
    Liu, Zhao
    Chen, Lifang
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian University of Technology (DUT), China.
    Efficient molecular ruthenium catalysts containing anionic ligands for water oxidation2016Inngår i: DALTON TRANSACTIONS, ISSN 1477-9226, Vol. 45, nr 46, s. 18459-18464Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two new mononuclear Ru complexes RuII(bipa)(pic) 3 (1; H(2)bipa = 6-(1H-benzo[d] imidazol-2-yl) picolinic acid, pic = 4-picoline) and RuII(pbic)(pic) 3 (2; H(2)pbic = 2-(pyridin-2-yl)-1H-benzo[d]imidazole-7-carboxylic acid, pic = 4-picoline) based on anionic ligands were successfully synthesized, and characterized using NMR spectroscopy, mass spectrometry, and X-ray crystallography. These catalysts showed high activities and stabilities in water oxidation in homogeneous systems with a high turnover number of 2100 and a turnover frequency of 0.21 s(-1) for complex 1. The O-O band formation mechanism involved water nucleophilic attack. An active catalytic intermediate, i.e., RuIV-OH, was detected using high-resolution mass spectrometry.

  • 253.
    Ma, Gui-Bin
    et al.
    KTH, Tidigare Institutioner, Kemi.
    Maliarik, Mikhail
    KTH, Tidigare Institutioner, Kemi.
    Sun, Licheng
    KTH, Tidigare Institutioner, Kemi.
    Glaser, Julius
    KTH, Tidigare Institutioner, Kemi.
    Novel porphyrin-thallium-platinum complex with naked metal-metal bond: multinuclear NMR characterization of (tpp)Tl-Pt(CN)(5) (2-) and (thpp)Tl-Pt(CN)(5) (2-) in solution2004Inngår i: Inorganica Chimica Acta, ISSN 0020-1693, E-ISSN 1873-3255, Vol. 357, nr 14, s. 4073-4077Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The novel porphyrin-thallium-platinum complexes with naked metal-metal bond, with the composition [(tpp)Tl-Pt(CN)(5)](2-) (1) and [(thpp)Tl-Pt(CN)(5)](2-) (2) (tpp = tetraphenylporphrin and thpp = tetrakis(4-hydroxyphenyl)-porphine), were synthesized and characterised by multinuclear NMR (Tl-205, Pt-195, C-13 and H-1) and Raman spectroscopies in solution. The presence of a direct Pt-Tl metal-metal bond in the complexes is convincingly confirmed by a very strong one-bond Pt-195-Tl-205 spin-spin coupling (47.8 and 48.3 kHz for 1 and 2, respectively) detected in both Pt and Tl NMR spectra. The corresponding force constant in molecule 1, 1.92 Ncm(-1), was calculated using Raman stretching frequency of the Pt-T1 vibration and is characteristic for a single metal-metal bond.

  • 254.
    Marinado, Tannia
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Edvinsson, Tomas
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Boschloo, Gerrit
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Influence of π-Conjugation Units in Organic Dyes for Dye-Sensitized Solar Cells2007Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 111, nr 4, s. 1853-1860Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two organic dyes with the general structure donor-conjugated chain-acceptor (D-pi-A) have been investigated as sensitizers for nanocrystalline TiO2 solar cells. The electron donor and acceptor groups were pyrrolidine and cyano acrylic acid, respectively. The conjugated chain of 2-cyano-3-{5-[2-(4-pyrrolidin-1-ylphenyl)vinyl]thiophen-2-yl}acrylic acid contains one phenyl ring and a thiophene unit and is therefore denoted PT, while for 2-cyano-3-{5 -[2-(5-pyrrolidin-1-ylthiophen-2-yl)vinyl]thiophen-2-yl}acrylic acid the phenyl ring is replaced by a second thiophene unit (TT). Solar-to-electrical energy conversion efficiencies under simulated AM 1.5 irradiation (1000 W m(-2)) of 2.3% were obtained for solar cells based on PT but of less than 0.05% for those based on TT. The reasons for the dramatic difference of the efficiencies were analyzed. Photoinduced absorption measurements revealed that the TT dye was not properly regenerated by redox electrolyte after electron injection. This sluggish regeneration is probably due to the 0.3 V less positive HOMO level for TT dye compared to the PT dye, resulting in a lower driving force for regeneration of the oxidized dye by iodide in the electrolyte. In addition, regeneration of the oxidized TT dye and electron injection from the excited TT dye may be poor due to formation of dye aggregates/complexes, as FT-IR measurements show an excess of not properly and/or unidentate bound TT dye molecules instead of bidentate bound PT dye molecules. The results highlight that small structural change of dyes results in significant changes in redox energies and binding features, affecting dramatically the performance of these dyes in dye-sensitized solar cells.

  • 255.
    Marinado, Tannia
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagberg, Daniel P.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Edvinsson, Tomas
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    Boschloo, Gerrit
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Tian, Haining
    Yang, Xixhuan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Energy level tuning of organic dyes for fundamental studies of the oxide/dye/electrolyte interface in solar cellsManuskript (Annet vitenskapelig)
  • 256.
    Marinado, Tannia
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hahlin, Maria
    Jiang, Xiao
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Quintana, Maria
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Johansson, Erik M J
    Gabrielsson, Erik
    Plogmaker, Stefan
    Hagberg, Daniel P
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Boschloo, Gerrit
    Zakeeruddin, M
    Gratzel, Michael
    Siegbahn, Hans
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Rensmo, Håkan
    Surface Molecular Quantification and Photoelectrochemical Characterization of Mixed Organic Dye and Coadsorbent Layers on TiO2 for Dye-Sensitized Solar Cells2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 27, s. 11903-11910Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Different molecular layers on TiO2 were prepared by using the p-dimethylaniline triphenylamine based organic dye, D29, together with the coadsorbents decylphosphonic acid (DPA), dineohexyl bis(3,3-dimethylbutyl)phosphinic acid (DINHOP), and chenodeoxycholic acid (CDCA). The surface molecular structure of dye and coadsorbent layers on TiO2 was investigated by photoelectron spectroscopy (PES). A focus was to determine the surface molecular concentrations using characteristic photoelectron core levels. Dye-sensitized solar cells (DSCs) were prepared from the same substrate and were further characterized by photoelectrochemical methods. Together the investigation gives information on the arrangement of the mixed molecular layer and a first insight to the extent to which the coadsorbents exchange with dye molecules on the TiO2 surface for the examined conditions.

  • 257.
    Marinado, Tannia
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Nonomura, Kazuteru
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Nissfolk, Jarl
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Karlsson, Martin K
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagberg, Daniel P
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Mori, Shogo
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    How the Nature of Triphenylamine-Polyene Dyes in Dye-Sensitized Solar Cells Affects the Open-Circuit Voltage and Electron Lifetimes2010Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 26, nr 4, s. 2592-2598Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three donor-linker-acceptor triphenylamine-based cyanoacrylic acid organic dyes used For dye-sensitized solar cells (DSCs) have been examined with respect to their effect on the open-circuit voltage (V-oc). Our previous study showed a decrease in V-oc for DSCs based oil dyes with increased molecular size (increased linker conjugation). In the present study, we investigate the origin of V-oc with respect to (i) conduction band (E-CB) positions of TiO2 and (ii) degree of recombination between electrons in TiO2 and electrolyte acceptor species at the interface. These parameters were Studied its it function of dye structure, dye load, and I-2 concentration. Two types of behavior were identified: the smaller polyene dyes show a surface-protecting effect preventing recombination upon increased dye loading, whereas the larger dyes enhance the recombination. How the different dye structures affect the recombination is discussed in terms of dye surface blocking and intermolecular interactions between dyes and electrolyte acceptor species.

  • 258. Meng, Peng
    et al.
    Wang, Mei
    Yang, Yong
    Zhang, Shuai
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, China.
    CdSe quantum dots/molecular cobalt catalyst co-grafted open porous NiO film as a photocathode for visible light driven H-2 evolution from neutral water2015Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, nr 37, s. 18852-18859Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An active noble-metal-free photocathode was fabricated by co-grafting water-soluble thioglycolic acid-stabilized CdSe quantum dots and a molecular cobaloxime catalyst (CoP) through chemical linkage on a p-type open porous NiO film. This photocathode was used as a working electrode in a three-electrode cell, which displayed a photocurrent density up to 110 mu A cm(-2) at an applied potential of 0 V vs. NHE in 0.1 M Na2SO4 solution at pH 6.8 upon visible light illumination. The comparative studies showed that the open porous NiO/CdSe electrode did display a higher photocurrent density than that exhibited by an analogous planar NiO/CdSe electrode made by doctor-blading a NiO paste. Long-time photoelectrolysis experiments revealed that about 83% of the photocurrent density remained after 3.5 h illumination at 0.2 V vs. NHE. The open porous NiO/CdSe/CoP photocathode showed a considerably better current density and photocatalytic stability compared to the so-far reported dye-or QD-sensitized NiO cathodes with a cobaloxime catalyst chemically attached or physically adsorbed on the electrode surface under similar conditions.

  • 259.
    Monhaphol, Thitinun
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Andersson, Samir
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Isolated Supramolecular [Ru(bpy)(3)]-Viologen-[Ru(bpy)(3)] Complexes with Trapped CB[7,8] and Photoinduced Electron-Transfer Study in Nonaqueous Solution2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, Vol. 17, nr 41, s. 11604-11612Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The synthesis of two supramolecular diruthenium complexes, 1 subset of CB[7] and 1 subset of CB[8] (CB[n]=cucurbit[n]uril), which contain the respective host CB[7] and CB[8], were synthesized and isolated. In the case of host CB[8], the desired supramolecular complex was obtained by utilizing dihydroxynapthalene as a template during the synthesis. The (1)H NMR spectra, electrochemistry, and photochemistry of these supramolecular complexes were performed in nonaqueous solution. The results show that both CB[7,8] hosts mainly bind to the linker part in solution in acetonitrile. This binding also lowers the oxidation potential of the ruthenium metal center and hinders the quenching effect by the viologen moiety. It has also been shown that external methylviologen can be included into 1 subset of CB[8]. Analysis with NMR spectroscopy, electrochemistry, and photochemistry clearly shows a viologen radical dimer formation between the bound viologen and free methylviologen, thereby showing that the unique abilities of the CB[8] host can be utilized even in nonaqueous solution.

  • 260. Na, Yong
    et al.
    Pan, Jingxi
    Wang, Mei
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Intermolecular electron transfer from photogenerated Ru(bpy)(3)(+) to 2Fe2S model complexes of the iron-only hydrogenase active site2007Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 46, nr 10, s. 3813-3815Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Visible light-driven intermolecular electron transfer was observed from a reduced species Ru(bpy)(3)(+), photogenerated via a reductive quenching of the ruthenium photosensitizer by a diethyldithiocarbamate anion, to bioinspired [2Fe2S] model complexes of the iron-only hydrogenase active site. The results indicate that Ru(bpy)(3)(2+) can act as a photoactive functional model of the [4Fe4S] cluster, playing the role of an electron-transfer relay. The photogenerated (FeFe0)-Fe-I species, which is proposed to be a crucial intermediate for proton reduction catalyzed electrochemically by the [2Fe2S] complexes, gives promise in the light-driven dihydrogen evolution using diiron complexes as surrogates of noble platinum catalysts.

  • 261. Na, Yong
    et al.
    Wang, Mei
    Jin, Kun
    Zhang, Rong
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    An approach to water-soluble hydrogenase active site models: Synthesis and electrochemistry of diiron dithiolate complexes with 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo 3.3.1 nonane ligand(s)2006Inngår i: Journal of Organometallic Chemistry, ISSN 0022-328X, E-ISSN 1872-8561, Vol. 691, nr 23, s. 5045-5051Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to improve the hydro- and protophilicity of the active site models of the Fe-only hydrogenases, three diiron dithiolate complexes with DAPTA ligand(s) (DAPTA=3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonanc), (mu-pdt)[Fe(CO)(2)][Fe(CO)(2)(DAPTA)] (1, pdt = 1,3-propanedithiolato), (mu-pdt)[Fe(CO)(2)(DAPTA)](2) (2) and (mu-pdt)[Fe(CO)(2)(PTA)][Fe(CO)(2)(DAPTA)] (3), were prepared and spectroscopically characterized. The water solubility of DAPTA-coordinate complexes 1-3 is better than that of the PTA-coordinate analogues. With complexes 1-3 as electrocatalysts, the overvoltage is reduced by 460-770 mV for proton reduction from acetic acid at low concentration in CH3CN. Significant decrease, up to 420 mV, in reduction potential for the Fe(I)Fe(I) to Fe(I)Fe(0) process and the curve-crossing phenomenon are observed in cyclic voltammograms of 2 and 3 in CH3CN/H2O mixtures. The introduction of the DAPTA ligand to the diiron dithiolate model complexes indeed makes the water solubility of 2 and 3 sufficient for electrochemical studies in pure water, which show that the proton reduction from acetic acid in pure water is electrochemically catalyzed by 2 and 3 at ca. -1.3 V vs. NHE.

  • 262. Na, Yong
    et al.
    Wang, Mei
    Pan, Jingxi
    Zhang, Pan
    Akermark, Bjoern
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Visible light-driven electron transfer and hydrogen generation catalyzed by bioinspired 2Fe2S complexes2008Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 47, nr 7, s. 2805-2810Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Complexes [{(mu-SCH2)(2)NCH2C6H5){Fe(CO)(2)L-1){Fe(CO)(2)L-2}] (L-1 = CO, L-2 = P(Pyr)(3), 2; L-1 = L-2 = P(Pyr)(3), 3) were prepared, which have the lowest reduction potentials for the mono- and double-CO-displaced diiron complexes reported so far. Hydrogen evolution, driven by visible light, was successfully observed for a three-component system, consisting of a ruthenium polypyridine complex, the biomimetic model complex 2 or 3, and ascorbic acid as both electron and proton donor in CH3CN/H2O. The electron transfer from photogenerated Ru(bPY)(3)(+) to 2 or 3 was detected by laser flash photolysis. Under optimal conditions, the total turnover number for hydrogen evolution was 4.3 based on 2 and 86 based on Ru(bPY)(3)(2+) in a three-hour photolysis.

  • 263. Ni, Wenjun
    et al.
    Gurzadyan, Gagik G.
    Zhao, Jianzhang
    Che, Yuanyuan
    Li, Xiaoxin
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Singlet Fission from Upper Excited Electronic States of Cofacial Perylene Dimer2019Inngår i: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 10, nr 10, s. 2428-2433Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Singlet fission directly from the upper excited vibrational and electronic states of cofacial perylene dimers, bypassing the relaxed state S-1, was detected within 50 fs. This process competes well with vibrational cooling in S-1 (4.7-7.0 ps) and S-2 -> S-1 internal conversion (380 fs). The singlet fission has the energy threshold E = 3.06 eV. Other competitive relaxation processes are excimer and dimer cation formation on an ultrafast time scale. Excitation to higher energy levels (4.96 eV) leads to a higher efficiency of singlet fission.

  • 264.
    Ning, Zhijun
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Tian, Haining
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Qin, Haiyan
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Zhang, Qiong
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fu, Ying
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Wave-Function Engineering of CdSe/CdS Core/Shell Quantum Dots for Enhanced Electron Transfer to a TiO2 Substrate2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 35, s. 15184-15189Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we have synthesized a series of core/shell quantum dots (QDs) for the purpose of enhancing the electron transfer from the dots to a TiO2 substrate. We make use of the fact that CdSe is a small-bandgap material compared with CdS; therefore, in a common CdSe/CdS core/shell QD, the photo-excited electron is confined deeply in the CdSe core. By special construction of the CdS/CdSe core/shell QDs, referred as reversed type-I, the electron wave function will distribute largely in the shell region. This facilitates the transfer of the electron from the QD to the TiO2 substrate, resulting in significantly improved electron-injection efficiency. Such an enhanced electron-injection efficiency was confirmed by fluorescence lifetime decay measurements, showing the largest lifetime reduction after that the QDs were adsorbed on the TiO2 surface. The reversed type-I CdS/CdSe QDs show a much higher photon-to-current conversion efficiency than type-I CdSe/CdS and CdSe QDs without shell. Furthermore, by chemical-bath depositing of CdS on the QD-sensitized electrode to form a quantum-well structure, the electron recombination between the QDs and the redox couple was reduced, hence further enhancing the electron-injection efficiency. The absorbed-photon-to-current efficiency of the quantum well CdS/CdSe/CdS sensitized solar cells reaches a value as high as 60%.

  • 265.
    Ning, Zhijun
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Tian, Haining
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Yuan, Chunze
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Fu, Ying
    KTH, Skolan för bioteknologi (BIO).
    Qin, Haiyan
    KTH, Skolan för bioteknologi (BIO).
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi (stängd 20110512).
    Solar cells sensitized with type-II ZnSe-CdS core/shell colloidal quantum dots2011Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 47, nr 5, s. 1536-1538Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Type-II quantum dots (QDs) were applied for QDs-sensitized solar cells for the first time and showed prominent absorbed photon to current conversion efficiency.

  • 266.
    Ning, Zhijun
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Tian, Haining
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Yuan, Chunze
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Fu, Ying
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Pure Organic Redox Couple for Quantum-Dot-Sensitized Solar Cells2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 23, s. 6330-6333Artikkel i tidsskrift (Fagfellevurdert)
  • 267.
    Ning, Zhijun
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Yuan, Chunze
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Tian, Haining
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fu, Ying
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Li, Lin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Type-II colloidal quantum dot sensitized solar cells with a thiourea based organic redox couple2012Inngår i: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 22, nr 13, s. 6032-6037Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, one kind of organic electrolyte based on tetramethylthiourea is employed for quantum dot sensitized solar cells (QDSCs). By reducing the impedance between the electrolyte and the counter electrode, the fill factor of such organic electrolyte based QDSCs is significantly improved. It is possible to substantially increase the photovoltage and to reach an efficiency three times higher than that of a commonly used inorganic electrolyte. The light harvesting ability of the organic electrolyte based QDSCs is successfully extended by using type-II QDs, where the adsorption of ZnS gives an additional advantage in further enhancing the stability of the cells. It is observed that core/shell ZnSe/CdS type-II QDs give higher electron injection than CdS/ZnSe QDs, proving that the electron distribution in the QDs is important for the electron extraction. A full working mechanism of the organic redox couple for the QDSCs is proposed.

  • 268.
    Ning, Zhijun
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Yuan, Chunze
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Tian, Haining
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Quantum rod-sensitized solar cells2011Inngår i: ChemSusChem, ISSN 1864-5631, Vol. 4, nr 12, s. 1741-1744Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An electron injection highway: CdSe nanorods with CdS seed material were applied to a quantum rod-sensitized TiO 2 solar cell that showed a higher electron injection efficiency than analogous quantum dot-sensitized solar cells: reducing the nanocrystals carrier confinement dimensions can improve electron injection efficiency of nanocrystal-sensitized solar cells.

  • 269.
    Nonomura, Kazuteru
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Xu, Yunhua
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Marinado, Tannia
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagberg, Daniel P.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Zhang, Rong
    Boschloo, Gerrit
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    The Effect of UV-Irradiation (under Short-Circuit Condition) on Dye-Sensitized Solar Cells Sensitized with a Ru-Complex Dye Functionalized with a (diphenylamino)Styryl-Thiophen Group2009Inngår i: International Journal of Photoenergy (Online), ISSN 1110-662X, E-ISSN 1687-529XArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new ruthenium complex, cis-di(thiocyanato)(2,2'-bipyridine-4,4'-dicarboxylic acid)(4,4'-bis(2-(5-(2-(4-diphenylaminophenyl)ethenyl)-thiophen-2-yl)eth enyl)-2,2'-bipyridine)ruthenium(II) (named E322) has been synthesized for use in dyesensitized solar cells (DSCs). Higher extinction coefficient and a broader absorption compared to the standard Ru-dye, N719, were aimed. DSCs were fabricated with E322, and the efficiency was 0.12% initially. (4.06% for N719, as reference). The efficiency was enhanced to 1.83% by exposing the cell under simulated sunlight containing UV-irradiation at short-circuit condition. The reasons of this enhancement are (1) enhanceing electron injection from sensitizer to TiO2 following a shift toward positive potentials of the conduction band of TiO2 by the adsorption of protons or cations from the sensitizer, or from the redox electrolyte and (2) improving the regeneration reaction of the oxidized dye by the redox electrolyte by the dissolution of aggregated dye from the surface of TiO2 following the treatment.

  • 270. Nyhlén, Jonas
    et al.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Åkermark, Björn
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Privalov, Timofei
    Evolution of O-2 in a Seven-Coordinate Ru-IV Dimer Complex with a [HOHOH] (-) Bridge: A Computational Study2010Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 49, nr 10, s. 1773-1777Artikkel i tidsskrift (Fagfellevurdert)
  • 271. Ou, J.
    et al.
    Xiang, J.
    Liu, J.
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, Dalian University of Technology, Dalian, 116024, China.
    Surface-Supported Metal-Organic Framework Thin-Film-Derived Transparent CoS 1.097 @N-Doped Carbon Film as an Efficient Counter Electrode for Bifacial Dye-Sensitized Solar Cells2019Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, nr 16, s. 14862-14870Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An effective design for counter electrode (CE) catalytic materials with superior catalytic activity, excellent stability, low cost, and a facile fabrication process is urgently needed for industrialization of dye-sensitized solar cells (DSSCs). Herein, we report a facile in situ method to fabricate transparent CoS 1.097 anchored on an N-doped carbon film electrode through sulfurization of a cobalt-metalloporphyrin metal-organic framework thin film on fluorine-doped tin oxide glass. The transparent film as counter electrode in bifacial DSSCs exhibited higher power conversion efficiency (9.11% and 6.64%), respectively, from front and rear irradiation than that of Pt (8.04% and 5.87%). The uniformly dispersed CoS 1.097 nanoparticles on an N-doped carbon film provide a large catalytic active area and facilitate the electron transfer, which leads to the excellent catalytic ability of the CoS 1.097 @N-doped carbon film. In addition, the in situ preparation of the uniform film with a nanosheet structure offers high electrical conductivity and unobstructed access for the diffusion of triiodide to available electroactive sites, resulting in excellent device performance with superior long-term stability over 1000 h under natural conditions.

  • 272. Pan, Y. -Z
    et al.
    Wang, Y. -G
    Liu, J. -H
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    10-Ethyl-3-(5-methyl-1,3,4-oxadiazol-2-yl)-10H-phenothiazine2012Inngår i: Acta Crystallographica Section E: Structure Reports Online, ISSN 1600-5368, E-ISSN 1600-5368, Vol. 68, nr 3, s. o649-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the title compound, C 17H 15N 3OS, the phenothia-zine ring system is slightly bent, with a dihedral angle of 13.68 (7)° between the benzene rings. The dihedral angle between the oxadiazole ring and the adjacent benzene ring is 7.72 (7)°. In the crystal, a π-π interaction with a centroid-centroid distance of 3.752 (2) Å is observed between the benzene rings of neighbouring molecules.

  • 273. Pan, Y. -Z
    et al.
    Wang, Y. -G
    Liu, Jianhui
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    2-(5-Bromothiophen-2-yl)-5-[5-(10-ethyl-phenothia-zin-3-yl)thiophen-2-yl] -1,3,4-oxadiazole2012Inngår i: Acta Crystallographica Section E: Structure Reports Online, ISSN 1600-5368, E-ISSN 1600-5368, Vol. 68, nr 5, s. o1383-o1384Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The molecule of the title compound, C 24H 16BrN 3OS 3, contains three approximately planar fragments, viz. an oxadiazole ring plus two adjacent thiophene groups, and two phenothia-zine benzene rings, with largest deviations from the least-squares planes of 0.051 (3), 0.019 (4) and 0.014 (3) Å, respectively. The phenothia-zine unit adopts a butterfly conformation, with a dihedral angle of 38.06 (15)°between the terminal benzene rings. The dihedral angle between the 2,5-bis-(thiophen-2- yl)oxadiazole unit and the attached benzene ring is 15.35 (11)°. In the crystal, molecules form stacks along the b-axis direction; neighboring molecules within the stack are related by inversion centers, with shortest inter-centroid separations of 3.741 (2) and 3.767 (2) Å.

  • 274. Pettersson, Henrik
    et al.
    Gruszecki, Tadeusz
    Schnetz, Christine
    Streit, Micha
    Xu, Yunhua
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Gorlov, Mikhail
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Oorganisk kemi (stängd 20110630).
    Boschloo, Gerrit
    Häggman, Leif
    Hagfeldt, Anders
    Parallel-connected monolithic dye-sensitised solar modules2010Inngår i: Progress in Photovoltaics, ISSN 1062-7995, E-ISSN 1099-159X, Vol. 18, nr 5, s. 340-345Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Light-soaking and high-temperature storage testing of monolithic dye-sensitised solar modules with total area module efficiencies above 5% have been performed. Our experiences from the development of a four-layer monolithic dye-sensitised solar test cell for comparative testing of material components for dye-sensitised solar cells have directed our module development to a novel device design consisting of parallel-connection of individual monolithic cells. The results from the accelerated testing of the modules (total area of 17.0 cm(2)) with four parallel-connected cells (active area of 3.38 cm(2)/cell) are equivalent to those obtained for the monolithic single test cells when using identical device components. The successful transfer from cell to module stability is an important milestone in our ambition to develop a low-cost Photovoltaic (PV) technology. Moreover, our results indicate that intensified research and development to define the procedures for relevant accelerated testing of dye-sensitised solar modules is urgently required.

  • 275. Privalov, Timofei
    et al.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Akermark, Bjorn
    Catalytic water oxidation: DFT study of a competitive involvement of Lewis acid-Lewis base cooperation and radical coupling2011Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 242, s. 490-INOR-Artikkel i tidsskrift (Fagfellevurdert)
  • 276.
    Privalov, Timofei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Akermark, Bjorn
    Liu, Jianhui
    Gao, Yan
    Wang, Mei
    A computational study of O-O bond formation catalyzed by monoand Bis-Mn-IV-Corrole complexes2007Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 46, nr 17, s. 7075-7086Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A detailed computational study of O-O bond formation, catalyzed by monomeric and dimeric Mn-corrole complexes, is reported. The model explicitly takes into account the solvent, with respect to the first and second coordination spheres, while the bulk solvent is described by the polarizable continuum model. Two reaction mechanisms are proposed and computationally characterized: the concerted and the two-step mechanisms. The concerted mechanism is based on a OH--(MnO)-O-IV interaction via the outer-sphere pathway involving the bridging solvent molecules in the first coordinating sphere. The two-step mechanism is proposed to operate via the coordination of a hydroxide to the Mn-Iv ion, forming a MnO(OH)(-)-corrole complex with a strongly nonplanar corrole ligand. Comparison of the proposed mechanisms with available experimental data. is performed.

  • 277. Privalov, Timofei
    et al.
    Åkermark, Björn
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    The O-O Bonding in Water Oxidation: the Electronic Structure Portrayal of a Concerted Oxygen Atom-Proton Transfer Pathway2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 30, s. 8313-8317Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The two-phased reaction: Calculations on the monomeric ruthenium catalyst with 1,10-phenanthroline-2,9-dicarboxylic acid reveals an interaction of the RuV=O complex with water that proceeds through two main phases and involves partial charge separation in an early encounter complex. Further along the reaction path, that effect leads to an electronic reorganization in the Ru complex; this directs the donor-acceptor interaction between the attacking water and the COO-group in concert with the O-atom transfer to form an O-O bond via a relatively low-energy barrier (see graphic).

  • 278.
    Qin, Peng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Linder, Mats
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Boschloo, Gerrit
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    High Incident Photon-to-Current Conversion Efficiency of p-Type Dye-Sensitized Solar Cells Based on NiO and Organic Chromophores2009Inngår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 21, nr 29, s. 2993-2996Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The synthesis and characterization of an organic dye, P4, together with its performance in p-type dye-sensitized solar cells (DSSCs) is presented. A solar-cell device based on P4 and an electrolyte that contains the I-/I-3(-) couple in acetonitrile yielded an IPCE value of 44% on a transparent NiO film only 1-1.4 mu m thick, the highest value obtained so far.

  • 279.
    Qin, Peng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Wiberg, Joanna
    Gibson, Elizabeth A.
    Linder, Mats
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Li, Lin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Albinsson, Bo
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Synthesis and Mechanistic Studies of Organic Chromophores with Different Energy Levels for p-Type Dye-Sensitized Solar Cells2010Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 10, s. 4738-4748Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of donor-pi-acceptor dyes with different electron-withdrawing groups were designed and synthesized for p-type dye-sensitized Solar cells. The modification of dye structures shows significant influence on the photophysical, electrochemical, and photovoltaic performance of the dyes. DSSCs based on these dyes show maximum 63% and minimum 6% of incident monochromatic photon-to-current conversion efficiencies. The two dyes with the highest (P1) and lowest (P3) efficiencies were Studied by femtosecond transient absorption spectroscopy, which shows a fast injection rate of more than (250 fs)(-1) for both dyes. Such fast injection corresponds to more than 90% injection efficiency. The photoinduced absorption Spectroscopy Study of sensitized NiO films in the presence of electrolyte showed poor regeneration of 113 due to all insufficient driving force. This, together with aggregation of the dye on the NiO film, explained the poor solar cell performance.

  • 280.
    Qin, Peng
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Zhu, Hongjun
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi (stängd 20110630). KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Edvinsson, Tomas
    Boschloo, Gerrit
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi (stängd 20110630).
    Hagfeldt, Anders
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi (stängd 20110630). 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.
    Design of an organic chromophore for p-type dye-sensitized solar cells2008Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 130, nr 27, s. 8570-8571Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A successful model for the design of efficient dyes for p-type dye-sensitized solar cells (DSSCs) is presented. As an example, a novel and efficient organic dye containing a triphenylamine chromophore has been synthesized and successfully applied in a p-type DSSC. The highest incident photon-to-current conversion efficiency (IPCE) of 18% in the visible region has been obtained, which is the highest value so far in p-type DSSCs. This is remarkably high, considering that only 600 nm thin NiO mesoporous films were used as p-type DSSC electrodes.

  • 281. Qu, Jishuang
    et al.
    Jiang, Xiaoqing
    Yu, Ze
    Lai, Jianbo
    Zhao, Yawei
    Hu, Maowei
    Yang, Xichuan
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Improved performance and air stability of perovskite solar cells based on low-cost organic hole-transporting material X60 by incorporating its dicationic salt2018Inngår i: Science in China Series B: Chemistry, ISSN 1674-7291, E-ISSN 1869-1870, Vol. 61, nr 2, s. 172-179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development of an efficient, stable, and low-cost hole-transporting material (HTM) is of great significance for perovskite solar cells (PSCs) from future commercialization point of view. Herein, we specifically synthesize a dicationic salt of X60 termed X60(TFSI)(2), and adopt it as an effective and stable "doping" agent to replace the previously used lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) for the low-cost organic HTM X60 in PSCs. The incorporation of this dicationic salt significantly increases the hole conductivity of X60 by two orders of magnitude from 10(-6) to 10(-4) S cm(-1). The dramatic enhancement of the conductivity leads to an impressive power conversion efficiency (PCE) of 19.0% measured at 1 sun illumination (100 mW cm(-2), AM 1.5 G), which is comparable to that of the device doped with LiTFSI (19.3%) under an identical condition. More strikingly, by replacing LiTFSI, the PSC devices incorporating X60(TFSI)(2) also show an excellent long-term durability under ambient atmosphere for 30 days, mainly due to the hydrophobic nature of the X60(TFSI)(2) doped HTM layer, which can effectively prevent the moisture destroying the perovskite layer. The present work paves the way for the development of highly efficient, stable, and low-cost HTM for potential commercialization of PSCs.

  • 282. Shen, J.
    et al.
    Wang, M.
    Gao, J.
    Han, H.
    Liu, H.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Improvement of Electrochemical Water Oxidation by Fine-Tuning the Structure of Tetradentate N4 Ligands of Molecular Copper Catalysts2017Inngår i: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 10, nr 22, s. 4581-4588Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two copper complexes, [(L1)Cu(OH2)](BF4)2 [1; L1=N,N′-dimethyl-N,N′-bis(pyridin-2-ylmethyl)-1,2-diaminoethane] and [(L2)Cu(OH2)](BF4)2 [2, L2=2,7-bis(2-pyridyl)-3,6-diaza-2,6-octadiene], were prepared as molecular water oxidation catalysts. Complex 1 displayed an overpotential (η) of 1.07 V at 1 mA cm−2 and an observed rate constant (kobs) of 13.5 s−1 at η 1.0 V in pH 9.0 phosphate buffer solution, whereas 2 exhibited a significantly smaller η (0.70 V) to reach 1 mA cm−2 and a higher kobs (50.4 s−1) than 1 under identical test conditions. Additionally, 2 displayed better stability than 1 in controlled potential electrolysis experiments with a faradaic efficiency of 94 % for O2 evolution at 1.58 V, when a casing tube was used for the Pt cathode. A possible mechanism for 1- and 2-catalyzed O2 evolution reactions is discussed based on the experimental evidence. These comparative results indicate that fine-tuning the structures of tetradentate N4 ligands can bring about significant change in the performance of copper complexes for electrochemical water oxidation.

  • 283. Shen, J.
    et al.
    Wang, M.
    Zhang, P.
    Jiang, J.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. Dalian University of Technology (DUT), China.
    Electrocatalytic water oxidation by copper(II) complexes containing a tetra- or pentadentate amine-pyridine ligand2017Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 53, nr 31, s. 4374-4377Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two water soluble copper(ii) complexes containing amine-pyridine ligands were found to be catalytically active for water oxidation reactions in basic solutions, with observed rate constants of 13.1-18.7 s−1. These complexes are robust in basic solutions and displayed good stability over 5 h of electrolysis in pH 11.5 phosphate buffer at 1.4 V vs. NHE.

  • 284. Shen, Z.
    et al.
    Xu, Bo
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Liu, Peng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Hu, Y.
    Yu, Y.
    Ding, H.
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Hua, J.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi. Dalian University of Technology (DUT), Dalian, China.
    Tian, H.
    High performance solid-state dye-sensitized solar cells based on organic blue-colored dyes2017Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 5, nr 3, s. 1242-1247Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development of novel photosensitizers with very high molar extinction coefficients and broad absorption spectra to enhance the light harvesting efficiency providing high PCEs for solid state dye sensitized solar cells (sDSCs) is a main target for improvement. In this work, two novel organic blue-colored dyes termed S4 and S5 with indeno[1,2-b]thiophene functionalized triphenylamine as the donor, 2,3-diphenylpyrido[3,4-b]pyrazine (PP) or 2,3-diphenylquinoxaline (QT) as the auxiliary acceptor and cyclopentadithiophene (CPDT) as the π-linker were designed and synthesized for sDSCs. S5 containing the QT unit as the electron-withdrawing group exhibits a high molar extinction coefficient of 6.3 × 104 M-1 cm-1 at 600 nm. Most importantly, the S5-based sDSCs shows record PCEs of 7.81% and 8.25% under one sun and 0.5 sun light intensities, respectively, exceeding the PCE of LEG4-based solar cells (7.34%). To the best of our knowledge, this is the first case where an organic blue-colored dye displays a PCE over 7.8% in sDSCs, thus representing record efficiencies for sDSCs. These results clearly show that molecular engineering is a viable way to develop blue-colored dyes with high molar extinction coefficients for use in highly efficient sDSCs. Also, blue-colored dyes open up co-sensitization strategies in combination with traditional organic dyes with yellow-red colours.

  • 285. Shi, Yu
    et al.
    Li, Xiaoyu
    Liu, Jianhui
    Jiang, Wenfeng
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    A Suzuki-type cross-coupling reaction of arylacetylene halides with arylboronic acids2011Inngår i: Applied organometallic chemistry, ISSN 0268-2605, E-ISSN 1099-0739, Vol. 25, nr 7, s. 514-520Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A PdCl(2)-catalyzed direct alkynylation of arylboronic acids to give diarylacetylenes is described. The optimal conditions using PdCl(2) as catalyst, MeOH-PhMe-H(2)O as solvent and K(2)CO(3) as base effectively suppressed the formation of homo-coupling product and afforded moderate to good yield of the desired unsymmetrical coupling product. This reaction represents a Suzuki-type sp(2)(C-B)-sp(C-X) cross-coupling.

  • 286. Shi, Yu
    et al.
    Li, Xiaoyu
    Liu, Jianhui
    Jiang, Wenfeng
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    PdCl2-catalyzed cross-coupling reaction of arylacetylene iodides with arylboronic acids to diarylacetylenes2010Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 51, nr 28, s. 3626-3628Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anew Suzuki-type cross-coupling reaction between 1-iodo-2-arylalkynes and arylboronic acids to afford a wide variety of functionalized diarylacetylenes in a mild reaction condition was developed. The reaction was catalyzed by a small amount of a structurally simple, commercially available, and stable PdCl2. This unique sp-sp(2) carbon-carbon bond formation provides a new protocol for the synthesis of diarylacetylenes, which is a new addition to the Suzuki cross-coupling reaction. (C) 2010 Elsevier Ltd. All rights reserved.

  • 287. Shifeng, Li
    et al.
    Xichuan, Yang
    Dingfeng, Qu
    Weihan, Wang
    Yu, Wang
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Molecular Design of D-pi-A Type II Organic Sensitizers for Dye Sensitized Solar Cells2012Inngår i: Chinese journal of chemistry, ISSN 1001-604X, E-ISSN 1614-7065, Vol. 30, nr 10, s. 2315-2321Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Four new type II organic dyes with D-pi-A structure (donor-p-conjugated-acceptor) and two typical type II sensitizers based on catechol as reference dyes are synthesized and applied in dye sensitized solar cells (DSCs). The four dyes can be adsorbed on TiO2 through hydroxyl group directly. Electron injection can occur not only through the anchoring group (hydroxyl group) but also through the electron-withdrawing group (?CN) located close to the semiconductor surface. Experimental results show that the type II sensitizers with a D-pi-A system obviously outperform the typical type II sensitizers providing much higher conversion efficiency due to the strong electronic push-pull effect. Among these dyes, LS223 gives the best solar energy conversion efficiency of 3.6%, with Jsc=7.3 mA center dot cm-2, Voc=0.69 V, FF=0.71, the maximum IPCE value reaches 74.9%.

  • 288.
    Song, Xinkai
    et al.
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yang, Xichuan
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Haoxin
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    An, Jincheng
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yu, Ze
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Xiuna
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland..
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, 2 Linggong Rd, Dalian 116024, Peoples R China.
    Improving energy transfer efficiency of dye-sensitized solar cell by fine tuning of dye planarity2019Inngår i: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 187, s. 274-280Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two push-pull metal-free sensitizers with 5,11-dihydroindolo[3,2-b]carbazole derivatives as electron-donating groups and 4-(benzo[c][1,2,5]thiadiazol-4-ylethynyl)benzoic acid (BTZ) as electron-withdrawing unit, denoted by SK201 and SK202, were synthesized and used for fabrication of dye-sensitized solar cells (DSSCs). SK202 contains a thienyl group between the donor and acceptor, whereas in SK201 the donor and acceptor are connected directly by a single bond. Introduction of a thienyl group improved the planarity of the dye molecule, broadened the absorption spectrum, enhanced the molar extinction coefficient, increased the dye loading on TiO2, and accelerated interface electron transfer on TiO2. This fine tuning of dye structure improved the performances of DSSCs based on SK202 sensitizers and gave a power conversion efficiency (PCE) of 11.0% (J(SC) 16.5 mA cm(-2), V-OC 932 mV, and fill factor 71.7%), compared with that of 7.2% for SK201, under standard AM1.5G solar irradiation (100 mW cm(-2)) with a Co(II/III) complex based redox couple.

  • 289.
    Staehle, Robert
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Tong, Lianpeng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Wang, Lei
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Fischer, Andreas
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Ahlquist, Mårten S. G.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Rau, Sven
    Water oxidation catalyzed by mononuclear ruthenium complexes with a 2,2′-bipyridine-6,6′-dicarboxylate (bda) ligand: How ligand environment influences the catalytic behavior2014Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 53, nr 3, s. 1307-1319Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new water oxidation catalyst [RuIII(bda)(mmi)(OH 2)](CF3SO3) (2, H2bda = 2,2′-bipyridine-6,6′-dicarboxylic acid; mmi = 1,3- dimethylimidazolium-2-ylidene) containing an axial N-heterocyclic carbene ligand and one aqua ligand was synthesized and fully characterized. The kinetics of catalytic water oxidation by 2 were measured using stopped-flow technique, and key intermediates in the catalytic cycle were probed by density functional theory calculations. While analogous Ru-bda water oxidation catalysts [Ru(bda)L2] (L = pyridyl ligands) are supposed to catalyze water oxidation through a bimolecular coupling pathway, our study points out that 2, surprisingly, undergoes a single-site water nucleophilic attack (acid-base) pathway. The diversion of catalytic mechanisms is mainly ascribed to the different ligand environments, from nonaqua ligands to an aqua ligand. Findings in this work provide some critical proof for our previous hypothesis about how alternation of ancillary ligands of water oxidation catalysts influences their catalytic efficiency.

  • 290. Sun, Hongfei
    et al.
    Wang, Mei
    Jin, Kun
    Ma, Chengbing
    Zhang, Rong
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Effect of deprotonation of a benzimidazolyl ligand on the redox potential and the structures of mononuclear ruthenium(II) complexes2007Inngår i: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, nr 26, s. 4128-4131Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A monoruthenium(II) complex of the benzimidazolyl ligand and its deprotonated counterpart were prepared and structurally characterized. The reversible protonation/deprotonation process of the ancillary ligand switches the redox potential of the ruthenium(II) core from 0.69 to 0.26 V vs. Ag/AgNO3. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

  • 291. Sun, Hongfei
    et al.
    Wang, Mei
    Li, Fei
    Li, Ping
    Zhao, Zhenbo
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Synthesis and structure of a mu-oxo diiron(III) complex with an N-pyridylmethyl-N,N-bis(4-methylbenzimidazol-2-yl)amine ligand and its catalytic property for hydrocarbon oxidation2008Inngår i: Applied organometallic chemistry, ISSN 0268-2605, E-ISSN 1099-0739, Vol. 22, nr 10, s. 573-576Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A mu-oxo diiron(III) complex [{Fe(pbba)Cl}(2)(mu-O)]Cl-2 (1, pbba = N-pyridylmethyl-N,N-bis(4-methylbenzimidazol-2-yl)amine) bearing multi-imidazolyl motifs was synthesized and characterized by X-ray crystallography to closely mimic the structural features of methane monooxygenase. As shown by its X-ray crystal structure, complex 1 is a centrosymmetric dimer with an Fe-O-Fe angle of 180 degrees, and pseudo-octahedral around each iron(III) center. The catalytic ability of title compound in the oxidation of alkane and alkene is investigated by employing tert-butylhydroperoxide and m-chloroperbenzoic acid as oxidants under mild conditions. The catalytic oxidation results showed that radical intermediate dominates the oxidation process.

  • 292.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi. Dalian University of Technology (DUT), China.
    A closer mimic of the oxygen evolution complex of photosystem II2015Inngår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 348, nr 6235, s. 635-636Artikkel i tidsskrift (Annet vitenskapelig)
  • 293.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Across the Board: Licheng Sun2015Inngår i: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 8, nr 1, s. 22-23Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this series of articles the board members of ChemSusChem discuss recent research articles that they consider of exceptional quality and importance for sustainability. In this entry, Prof. Licheng Sun discusses how solar fuel production (such as water splitting) can be made more efficient and economic on an industrial scale. Recommended is the work by Prof. Xuping Sun, who use non-noble metal-phosphorus-based nanostructures as efficient electrocatalysts for hydrogen generation from water.

  • 294.
    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.;KTH Royal Inst Technol, Dept Chem, S-10044 Stockholm, Sweden..
    PEROVSKITE SOLAR CELLS: Crystal crosslinking2015Inngår i: Nature Chemistry, ISSN 1755-4330, E-ISSN 1755-4349, Vol. 7, nr 9, s. 684-685Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 295. Sun, Licheng
    et al.
    Fan, X. H.
    Yao, P. J.
    Multi-objective fuzzy optimization algorithm for separation-recycle system2004Inngår i: Chinese Journal of Chemical Engineering, ISSN 1004-9541, E-ISSN 2210-321X, Vol. 12, nr 2, s. 221-226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Separation-recycle system is an important part in chemical process, and its optimization is a multi-objective problem. In this paper the process optimization procedure is proposed. The fuzzy optimization algorithm with the concept of relative importance degree (RID) is utilized to transfer multi-objective optimization (MO-O) model into a single-objective optimization (SO-O) framework. The treatment of process condensate in synthesis ammonia plant is taken as example to illustrate the optimization procedure, and the satisfactory result demonstrates feasibility and effectiveness of the suggested method.

  • 296.
    Sun, Shiguo
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Andersson, Samir
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhang, Rong
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Unusual partner radical trimer formation in a host complex of cucurbit 8 uril, ruthenium(II) tris-bipyridine linked phenol and methyl viologen2010Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 46, nr 3, s. 463-465Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A stable 1 : 1 : 1 inclusion complex of Ru(bpy)(3)-phenol (1), MV2+ and cucurbit[8]uril (CB[8]) is formed in aqueous solution. In the presence of triethanolamine (TEOA), a light-induced formation of unusual partner radical trimer 1-(MV+center dot)(2)-CB[8] has been observed for the first time.

  • 297. Sun, Shiguo
    et al.
    He, Yanxia
    Yang, Zhigang
    Pang, Yi
    Liu, Fengyu
    Fan, Jiangli
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Peng, Xiaojun
    Synthesis and DNA photocleavage study of Ru(bpy)(3)(2+)-(CH2)(n)-MV2+ complexes2010Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 39, nr 18, s. 4411-4416Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of Ru(bpy)(3)(2+)-(CH2)(n)-MV2+ complexes (1, n = 3, 4, 7) used for DNA photocleavage have been designed and synthesized. Under the irradiation of visible light, complexes 1 can cleave supercoiled plasmid DNA (pBR322) both in air and under Ar atmosphere. Radical species such as O2(-center dot), (OH)-O-center dot and the light-induced charge-separated (CS) oxidation state Ru(bpy)(3)(3+)-(CH2)(n)-MV+center dot are responsible for the cleavage. The longer the carbon chain linkage, the higher the DNA photocleavage efficiency. It is noted that backwards intramolecular electron transfer (ET) that exist in complexes 1 can lead to some decreasing effect on the cleavage result, while inclusion of complexes 1 with cucurbit[8]uril (CB[8]) inhibits the backwards ET to some extent, thereby increasing photocleavage efficiency.

  • 298. Sun, Shiguo
    et al.
    Li, Fusheng
    Liu, Fengyu
    Yang, Xue
    Fan, Jiangli
    Song, Fengling
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Peng, Xiaojun
    Synthesis and ECL performance of highly efficient bimetallic ruthenium tris-bipyridyl complexes2012Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 41, nr 40, s. 12434-12438Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to find the ideal carbon chain linkage number n for achieving the highest ECL in bimetallic ruthenium tris-bipyridyl complexes, a series of novel complexes [(bpy)(2)Ru(bpy')(CH2)(n)(bpy')Ru(bpy)(2)](4+) (1, where bpy is 2,2'-bipyridyl, n = 10, 12, 14) for a coreactant electrochemiluminescence (ECL) system have been synthesized. Their ECL properties at a Au electrode have been studied in 0.1 M phosphate buffer by using tripropylamine (TPrA), 2-(dibutylamino)ethanol (DBAE) and melamine as the coreactant, to compare with that of the previously reported bimetallic ruthenium analogous complex [(bpy)(2)Ru(bpy')(CH2)(8)(bpy')Ru(bpy)(2)](4+). The results demonstrate that the ECL intensity depends largely on the length of the saturated carbon chain linkage number n. The highest ECL is reached when n = 10, suggesting that a synergistic effect on ECL enhancement co-exists between the two intramolecular linked ruthenium activating centers. Density functional theory (DFT) calculation demonstrated that the optimized bond distances between Ru and N(bpy') are the longest both in the ground and the excited triplet states in the case of n = 10, while those for Ru and N(bpy) are the shortest in the excited triplet states. All these factors may be responsible for the above mentioned results. This study provided a methodology to further improve and tune ECL efficiency by using bimetallic ruthenium complexes linked by a flexible saturated carbon chain.

  • 299. Sun, Shiguo
    et al.
    Yang, Yang
    Liu, Fengyu
    Fan, Jiangli
    Kehr, Jan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Peng, Xiaojun
    ECL performance of ruthenium tris-bipyridyl complexes covalently linked with phenothiazine through different bridge2010Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 39, nr 37, s. 8626-8630Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three ruthenium complexes 1a, 1b and 1c were synthesized, in which the phenothiazine moiety was covalently linked to the ruthenium complex through a 4 carbon chain and amide bond, respectively. The results demonstrate that one PTZ moiety is preferred to reach a good ECL performance, and the 4 carbon chain linked complex 1a exhibits the highest ECL enhancement (up to about 9 times), in comparison with the commonly utilized parent Ru(bpy)(3)(2+), permitting a lower detection limit of 1.0 x 10(-14) M with signal to noise of 3 for 20 mM DBAE at Au electrode.

  • 300. Sun, Shiguo
    et al.
    Yang, Yang
    Liu, Fengyu
    Fan, Jiangli
    Peng, Xiaojun
    Kehr, Jan
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Intra- and intermolecular interaction ECL study of novel ruthenium tris-bipyridyl complexes with different amine reductants2009Inngår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, nr 38, s. 7969-7974Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of ruthenium(II) tris-bipyridyl complexes covalently linked with different amine reductants such as tripropylamine (TPrA), ethanolamine and diethanolamine for an electrochemiluminescence (ECL) system have been synthesized. Their ECL property at different working electrodes has been studied with and without the presence of TPrA, triethanolamine (TEOA) and 2-(dibutylamino) ethanol (DBAE) as the coreactant, respectively. The results demonstrate that the conjugated ruthenium complex alone can generate ECL through intramolecular interaction at a relatively low concentration, while with intermolecular interaction the ECL intensity increases progressively and becomes increasingly dominant with increasing complex concentration. For the coreactant system ECL, the amine coreactant needed for the conjugate complexes can be significantly lowered in comparison with that of the well known [Ru(bpy)(3)](2+)/TPrA system. One amine substituent is better for the system in order to diminish the steric hindrance, and the intramolecular amine reductant employed should have a similar structure with that of the additive amine coreactant to achieve a good ECL performance, which can pave a new route to further improving the ECL efficiency and increase the sensitivity of detection through combining both intra-and intermolecular interaction.

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