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Andersson, Richard L.ORCID iD iconorcid.org/0000-0002-0236-5420
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Publications (10 of 21) Show all publications
Pourrahimi, A. M., Andersson, R. ., Tjus, K., Ström, V., Björk, A. & Olsson, R. T. (2019). Making an ultralow platinum content bimetallic catalyst on carbon fibres for electro-oxidation of ammonia in wastewater. Sustainable Energy and Fuels, 3(8), 2111-2124
Open this publication in new window or tab >>Making an ultralow platinum content bimetallic catalyst on carbon fibres for electro-oxidation of ammonia in wastewater
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2019 (English)In: Sustainable Energy and Fuels, ISSN 2398-4902, Vol. 3, no 8, p. 2111-2124Article in journal (Refereed) Published
Abstract [en]

Electrocatalysis of wastewater containing ammonia is a promising alternative to chemical and biological water purification for several reasons, one being that energy-rich hydrogen gas is generated as a by-product while the reaction can be strictly controlled to meet demands. An objective has been to reduce the loading of expensive platinum (Pt) in the catalyst electrodes, and to reduce the poisoning of the metal surface during the electrolysis. Herein, the co-deposition of a copper-platinum (Cu-Pt) bimetallic alloy onto carbon filaments, stripped from their polymeric coating, is shown to give an electrocatalytic performance superior to that of pure Pt at a content of less than 3 wt% Pt. The key to the enhanced performance was to take advantage of micrometer-sized carbon filaments to distribute a very large bimetallic alloy surface uniformly over the filaments. The Cu-Pt-alloy-coated filaments also suffer less electrode poisoning than pure Pt, and are bonded more strongly to the carbon fibre due to better mechanical interlocking between the bimetallic alloy and the carbon filaments. High-resolution electron microscopy studies combined with a tuned electro-deposition process made it possible to tailor the catalyst micro/nano morphology to reach a uniform coverage, surrounding the entire carbon filaments. The results are promising steps towards large-scale wastewater treatment, combined with clean energy production from regenerated hydrogen.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2019
National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-255760 (URN)10.1039/c9se00161a (DOI)000476912900020 ()2-s2.0-85069762947 (Scopus ID)
Note

QC 20190809

Available from: 2019-08-09 Created: 2019-08-09 Last updated: 2019-08-09Bibliographically approved
Antonio, C., Andersson, R. ., Ström, V., Wu, Q., Sacchi, B., Farris, S., . . . Olsson, R. T. (2019). Preparation and Comparison of Reduced Graphene Oxide and Carbon Nanotubes as Fillers in Conductive Natural Rubber for Flexible Electronics. Omega, 4(2)
Open this publication in new window or tab >>Preparation and Comparison of Reduced Graphene Oxide and Carbon Nanotubes as Fillers in Conductive Natural Rubber for Flexible Electronics
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2019 (English)In: Omega, ISSN 0030-2228, E-ISSN 1541-3764, Vol. 4, no 2Article in journal (Refereed) Published
Abstract [en]

Conductive natural rubber (NR) nanocomposites were prepared by solvent-casting suspensions of reduced graphene oxide(rGO) or carbon nanotubes (CNTs), followed by vulcanization of the rubber composites. Both rGO and CNT were compatible as fillers in the NR as well as having sufficient intrinsic electrical conductivity for functional applications. Physical (thermal) and chemical reduction of GO were investigated, and the results of the reductions were monitored by X-ray photoelectron spectroscopy for establishing a reduction protocol that was useful for the rGO nanocomposite preparation. Field-emission scanning electron microscopy showed that both nanofillers were adequately dispersed in the main NR phase. The CNT composite displays a marked mechanical hysteresis and higher elongation at break, in comparison to the rGO composites for an equal fraction of the carbon phase. Moreover, the composite conductivity was always ca. 3-4 orders of magnitude higher for the CNT composite than for the rGO composites, the former reaching a maximum conductivity of ca. 10.5 S/m, which was explained by the more favorable geometry of the CNT versus the rGO sheets. For low current density applications though, both composites achieved the necessary percolation and showed the electrical conductivity needed for being applied as flexible conductors for a light-emitting diode. 

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Natural Sciences
Identifiers
urn:nbn:se:kth:diva-246150 (URN)10.1021/acsomega.8b03630 (DOI)000460237300107 ()2-s2.0-85061903645 (Scopus ID)
Note

QC 20190318

Available from: 2019-03-14 Created: 2019-03-14 Last updated: 2019-05-22Bibliographically approved
Paulraj, T., Riazanova, A. V., Yao, K., Andersson, R. ., Mullertz, A. & Svagan, A. J. (2017). Bioinspired Layer-by-Layer Microcapsules Based on Cellulose Nanofibers with Switchable Permeability. Biomacromolecules, 18(4), 1401-1410
Open this publication in new window or tab >>Bioinspired Layer-by-Layer Microcapsules Based on Cellulose Nanofibers with Switchable Permeability
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2017 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 18, no 4, p. 1401-1410Article in journal (Refereed) Published
Abstract [en]

Green, all-polysaccharide based microcapsules with mechanically robust capsule walls and fast, stimuli-triggered, and switchable permeability behavior show great promise in applications based on selective and timed permeability. Taking a cue from nature, the build-up and composition of plant primary cell walls inspired the capsule wall assembly, because the primary cell walls in plants exhibit high mechanical properties despite being in a highly hydrated state, primarily owing to cellulose microfibrils. The micro capsules (16 +/- 4 mu m in diameter) were fabricated using the layer-by-layer technique on sacrificial CaCO3 templates, using plant polysaccharides (pectin, cellulose nanofibers, and xyloglucan) only. In water, the capsule wall was permeable to labeled dextrans with a hydrodynamic diameter of similar to 6.6 nm. Upon exposure to NaC1, the porosity of the capsule wall quickly changed allowing larger molecules (similar to 12 nm) to permeate. However, the porosity could be restored to its original state by removal of NaCl, by which permeants became trapped inside the capsule's core. The high integrity of cell wall was due to the CNF and the ON/OFF alteration of the permeability properties, and subsequent loading/unloading of molecules, could be repeated several times with the same capsule demonstrating a robust microcontainer with controllable permeability properties.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2017
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:kth:diva-207697 (URN)10.1021/acs.biomac.7b00126 (DOI)000399061100036 ()28323423 (PubMedID)2-s2.0-85017647489 (Scopus ID)
Note

QC 20170531

Available from: 2017-05-31 Created: 2017-05-31 Last updated: 2019-10-08Bibliographically approved
Paulraj, T., Riazanova, A., Yao, K., Andersson, R. ., Müllertz, A. & Svagan, A. J. (2017). Bioinspired Layer-by-Layer Microcapsules Based on CelluloseNanofibers with Switchable Permeability. Biomacromolecules, 18, 1401-1410
Open this publication in new window or tab >>Bioinspired Layer-by-Layer Microcapsules Based on CelluloseNanofibers with Switchable Permeability
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2017 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 18, p. 1401-1410Article in journal (Refereed) [Artistic work] Published
National Category
Medical and Health Sciences Natural Sciences
Identifiers
urn:nbn:se:kth:diva-261397 (URN)10.1021/acs.biomac.7b00126 (DOI)
Available from: 2019-10-06 Created: 2019-10-06 Last updated: 2019-10-06
Wu, Q., Sundborg, H., Andersson, R. ., Peuvot, K., Guex, L., Nilsson, F., . . . Olsson, R. T. (2017). Conductive biofoams of wheat gluten containing carbon nanotubes, carbon black or reduced graphene oxide. RSC Advances, 7(30), 18260-18269
Open this publication in new window or tab >>Conductive biofoams of wheat gluten containing carbon nanotubes, carbon black or reduced graphene oxide
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2017 (English)In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 7, no 30, p. 18260-18269Article in journal (Refereed) Published
Abstract [en]

Conductive biofoams made from glycerol-plasticized wheat gluten (WGG) are presented as a potential substitute in electrical applications for conductive polymer foams from crude oil. The soft plasticised foams were prepared by conventional freeze-drying of wheat gluten suspensions with carbon nanotubes (CNTs), carbon black (CB) or reduced graphene oxide (rGO) as the conductive filler phase. The change in conductivity upon compression was documented and the results show not only that the CNT-filled foams show a conductivity two orders of magnitude higher than foams filled with the CB particles, but also that there is a significantly lower percolation threshold with percolation occurring already at 0.18 vol%. The rGO-filled foams gave a conductivity inferior to that obtained with the CNTs or CB particles, which is explained as being related to the sheet-like morphology of the rGO flakes. An increasing amount of conductive filler resulted in smaller pore sizes for both CNTs and CB particles due to their interference with the ice crystal formation before the lyophilization process. The conductive WGG foams with CNTs were fully elastic with up to 10% compressive strain, but with increasing compression up to 50% strain the recovery gradually decreased. The data show that the conductivity strongly depends on the type as well as the concentration of the conductive filler, and the conductivity data with different compressions applied to these biofoams are presented for the first time.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2017
Keywords
Carbon black, Carbon nanotubes, Compaction, Crude oil, Fillers, Graphene, Nanotubes, Pore size, Solvents, Yarn, Compressive strain, Conductive fillers, Conductive Polymer, Electrical applications, Orders of magnitude, Percolation thresholds, Reduced graphene oxides, Reduced graphene oxides (RGO), Foams
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-207441 (URN)10.1039/c7ra01082f (DOI)000399005500011 ()2-s2.0-85016468994 (Scopus ID)
Note

Funding details: EIT, European Institute of Innovation and Technology; Funding details: 243-2011-1436, Svenska Forskningsrådet Formas; Funding text: This work was financed by the Swedish Research Council Formas (No. 243-2011-1436). R. L. Andersson acknowledges the support from: European Institute of Innovation and Technology (EIT)-KIC InnoEnergy, Swedish Centre for Smart Grids and Energy Storage (SweGRIDS) and ABB AB.

QC 20170523

Available from: 2017-05-23 Created: 2017-05-23 Last updated: 2017-11-29Bibliographically approved
Andersson, R., Cabedo, L., Hedenqvist, M., Olsson, R. & Ström, V. (2016). Superparamagnetic [sic] nanofibers by electrospinning. RSC Advances, 6(26), 21413-21422
Open this publication in new window or tab >>Superparamagnetic [sic] nanofibers by electrospinning
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2016 (English)In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 6, no 26, p. 21413-21422Article in journal (Refereed) Published
Abstract [en]

The preparation of superparamagnetic thin fibers by electrospinning dispersions of nanosized magnetite (Fe3O4, SPIO/USPIO) in a PMMA/PEO polymer solution is reported. The saturation magnetization and coercivity were not affected by the concentration (0, 1, 10, 20 wt%) or fiber orientation, showing hysteresis loops with high magnetization (64 A m(2) kg(-1) @ 500 kA m(-1)) and record low coercivity (20 A m(-1)). AC susceptibility measurements vs. temperature at frequencies from 60 to 2 kHz confirmed superparamagnetism. The mechanical properties were only slightly dependent on the particle concentration because the nanoparticles were separately encapsulated by the polymer. A uniform fibre fracture cross section was found at all the investigated particle contents, which suggests a strong interaction at the polymer/particle interface. A theoretical value of the magnetic low field susceptibility was calculated from the Langevin function and compared with measured values. The results show a distinct but concentration-independent anisotropy, favoring magnetization along the fiber orientation with no sign of exchange interaction, explained by complete nanoparticle separation. Superparamagnetism cannot be inferred from particle size alone, so a relevant interpretation and criterion for superparamagnetism is presented, in accordance with Neel's original definition. From the measurements, it can be concluded that magnetic characterization can be used to elucidate the material morphology beyond the resolution of available microscopy techniques (TEM and SEM).

National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-184563 (URN)10.1039/c5ra27791d (DOI)000371535200016 ()2-s2.0-84959386416 (Scopus ID)
Note

QC 20160405

Available from: 2016-04-05 Created: 2016-04-01 Last updated: 2017-11-30Bibliographically approved
Alipour, N., Andersson, R. L., Olsson, R. T., Gedde, U. W. & Hedenqvist, M. S. (2016). VOC-Induced Flexing of Single and Multilayer Polyethylene Films As Gas Sensors. ACS Applied Materials and Interfaces, 8(15), 9946-9953
Open this publication in new window or tab >>VOC-Induced Flexing of Single and Multilayer Polyethylene Films As Gas Sensors
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2016 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 8, no 15, p. 9946-9953Article in journal (Refereed) Published
Abstract [en]

The differential swelling and bending of multilayer polymeric films due to the dissimilar uptake of volatile organic compounds (VOCs; n-hexane, limonene) in the different layers was studied. Motions of thin polyethylene films triggered by the penetrant were investigated to learn more about how their deformation is related to VOC absorption. Single layers of metallocene or low-density polyethylene, and multilayers (2-288-layers) of these in alternating positions were considered. Single-, 24-, and 288 layer films displayed no motion when uniformly subjected to VOCs, but they could display simple curving modes when only one side of the film was wetted with a liquid VOC. Two-layer films displayed simple bending when uniformly subjected to VOCs due to the different swelling in the two layers, but when the VOC was applied to only one side of the film, more complex modes of motion as well as dynamic oscillations were observed (e.g., constant amplitude wagging at 2 Hz for ca. 50 s until all the VOC had evaporated). Diffusion modeling was used to study the transport behavior of VOCs inside the films and the different bending modes. Finally a prototype VOC sensor was developed, where the reproducible curving of the two-layer film was calibrated with n-hexane. The sensor is simple, cost-efficient, and nondestructive and requires no electricity.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2016
Keywords
VOC sensor, multilayer films, modeling, flexing, polyethylene
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-187820 (URN)10.1021/acsami.6b01178 (DOI)000374812000047 ()2-s2.0-84966293370 (Scopus ID)
Note

QC 20160531

Available from: 2016-05-31 Created: 2016-05-30 Last updated: 2017-11-30Bibliographically approved
Liu, D., Wu, Q., Andersson, R. L., Hedenqvist, M. S., Farris, S. & Olsson, R. T. (2015). Cellulose nanofibril core-shell silica coatings and their conversion into thermally stable nanotube aerogels. Journal of Materials Chemistry A, 3(30), 15745-15754
Open this publication in new window or tab >>Cellulose nanofibril core-shell silica coatings and their conversion into thermally stable nanotube aerogels
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2015 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, no 30, p. 15745-15754Article in journal (Refereed) Published
Abstract [en]

A facile water-based one-pot reaction protocol for obtaining 20 nm thick uniform silica coatings on cellulose nanofibrils (CNFs) is herein presented for the first time. The fully covering silica shells result in the thermal stability of the CNFs improved by ca. 70 degrees C and 50 degrees C under nitrogen and oxygen atmospheres, respectively. Heating of the core-shell hybrid fibres to 400 degrees C results in complete degradation/removal of the CNF cores, and demonstrates an inexpensive route to large-scale preparation of silica nanotubes with the CNFs used as templates. The key to a uniform condensation of silica (from tetraethyl orthosilicate) to cellulose is a reaction medium that permits in situ nucleation and growth of the silica phase on the fibrils, while simultaneously matching the quantity of the condensed silica with the specific surface area of the CNFs. Most coatings were applied to bundles of 2-3 associated CNFs, which could be discerned from their negative imprint that remained inside the silica nanotubes. Finally, it is demonstrated that the coated nanofibrils can be freeze-dried into highly porous silica/cellulose aerogels with a density of 0.005 g cm(-3) and how these hybrid aerogels preserve their shape when extensively exposed to 400 degrees C in air (>6 h). The resulting material is the first reported silica nanotube aerogel obtained by using cellulose nanofibrils as templates.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2015
National Category
Chemical Sciences Energy Engineering
Identifiers
urn:nbn:se:kth:diva-172186 (URN)10.1039/c5ta03646a (DOI)000358211700048 ()2-s2.0-84937468455 (Scopus ID)
Note

QC 20150817

Available from: 2015-08-17 Created: 2015-08-14 Last updated: 2017-12-04Bibliographically approved
Strain, I. N., Wu, Q., Pourrahimi, A. M., Hedenqvist, M. S., Olsson, R. T. & Andersson, R. L. (2015). Electrospinning of recycled PET to generate tough mesomorphic fibre membranes for smoke filtration. Journal of Materials Chemistry A, 3(4), 1632-1640
Open this publication in new window or tab >>Electrospinning of recycled PET to generate tough mesomorphic fibre membranes for smoke filtration
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2015 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 3, no 4, p. 1632-1640Article in journal (Refereed) Published
Abstract [en]

Tough fibrous membranes for smoke filtration have been developed from recycled polyethylene terephthalate (PET) bottles by solution electrospinning. The fibre thicknesses were controlled from 0.4 to 4.3 mu m by adjustment of the spinning conditions. The highest fibre strength and toughness were obtained for fibres with an average diameter of 1.0 mu m, 62.5 MPa and 65.8 MJ m(-3), respectively. The X-ray diffraction (XRD) patterns of the fibres showed a skewed amorphous halo, whereas the differential scanning calorimetry (DSC) results revealed an apparent crystallinity of 6-8% for the 0.4 and 1 mu m fibres and 0.2% crystallinity for the 4.3 mu m fibres. Heat shrinkage experiments were conducted by exposing the fibres to a temperature above their glass transition temperature (T-g). The test revealed a remarkable capability of the thinnest fibres to shrink by 50%, which was in contrast to the 4.3 mu m fibres, which displayed only 4% shrinkage. These thinner fibres aka showed a significantly higher glass transition temperature (+15 degrees C) than that of the 4.3 mu m fibres. The results suggested an internal morphology with a high degree of molecular orientation in the amorphous segments along the thinner fibres, consistent with a constrained mesomorphic phase formed during their rapid solidification in the electric field. Air filtration was demonstrated with cigarette smoke as a model substance passed through the fibre mats. The 0.4 mu m fibres showed the most effective smoke filtration and a capacity to absorb 43x its own weight in smoke residuals. whereas the 1 mu m fibres showed the best combination of filtration capacity (32x) and mechanical robustness. The use of recycled PET in the form of nanofibres is a novel way of turning waste into higher-value products.

Keywords
Differential scanning calorimetry, Electric fields, Electrospinning, Fibrous membranes, Filtration, Glass, Glass transition, Microfiltration, Molecular orientation, Plastic bottles, Polyethylenes, Rapid solidification, Recycling, Shrinkage, Smoke, Spinning (fibers), Temperature, X ray diffraction, Average diameter, Cigarette smokes, Filtration capacity, Internal morphology, Mechanical robustness, Mesomorphic phase, Recycled polyethylene terephthalates, Spinning conditions
National Category
Materials Chemistry
Identifiers
urn:nbn:se:kth:diva-159360 (URN)10.1039/c4ta06191h (DOI)000346906100035 ()2-s2.0-84919884625 (Scopus ID)
Note

QC 20150130

Available from: 2015-01-30 Created: 2015-01-29 Last updated: 2017-12-05Bibliographically approved
Liu, D., Pourrahimi, A. M., Pallon, L. K. H., Andersson, R. L., Hedenqvist, M. S., Gedde, U. & Olsson, R. T. (2015). Morphology and properties of silica-based coatings with different functionalities for Fe3O4, ZnO and Al2O3 nanoparticles. RSC Advances, 5(59), 48094-48103
Open this publication in new window or tab >>Morphology and properties of silica-based coatings with different functionalities for Fe3O4, ZnO and Al2O3 nanoparticles
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2015 (English)In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 5, no 59, p. 48094-48103Article in journal (Refereed) Published
Abstract [en]

A facile single-step method for obtaining 2–3 nm thick silsesquioxane coatings on metal oxide nanoparticles using different carbon-functional silane precursors is presented. Iron oxide nanoparticles 8.5 nm in diameter were used as a model to evaluate the possibilities of forming different uniform carbon-functional coatings, ranging from hydrophobic to hydrophilic in character. Electron microscopy showed that all the coated nanoparticles could be described as core-shell nanoparticles with single Fe3O4 cores and carbon-functional silsesquioxane shells, without any core-free silicone oxide phase. Steric factors strongly influenced the deposited silicon oxide precursors with octyl-, methyl- or aminopropyl functionalities, resulting in coating densities ranging from 260 to 560 kg/m3. The methyl-functional coatings required several layers of silsesquioxane, 3–4, to build up the 2 nm structures, whereas only 1-2 layers were required for silsesquioxane with octyl groups. Pure silica coatings from tetraethoxysilanes were however considerably thicker due to the absence of steric hindrance during deposition, allowing the formation of 5–7 nm coatings of ca. 10 layers. The coating method developed for the iron oxide nanoparticles was generic and successfully transferred and up–scaled 30 and 325 times (by volume) to be applicable to 25 nm ZnO and 45 nm Al2O3 nanoparticles.

National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-168258 (URN)10.1039/C5RA04452A (DOI)000355703700096 ()2-s2.0-84930623622 (Scopus ID)
Funder
Swedish Foundation for Strategic Research , EM11-0022
Note

Updated from "Submitted" to "Published". QC 20150703

Available from: 2015-05-29 Created: 2015-05-29 Last updated: 2017-12-04Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0002-0236-5420

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