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Jeon I.,University of Tokyo | Cui K.,University of Tokyo | Chiba T.,University of Tokyo | Anisimov A.,Canatu Ltd. | And 6 more authors.
Journal of the American Chemical Society | Year: 2015

Organic solar cells have been regarded as a promising electrical energy source. Transparent and conductive carbon nanotube film offers an alternative to commonly used ITO in photovoltaics with superior flexibility. This communication reports carbon nanotube-based indium-free organic solar cells and their flexible application. Direct and dry deposited carbon nanotube film doped with MoOx functions as an electron-blocking transparent electrode, and its performance is enhanced further by overcoating with PEDOT:PSS. The single-walled carbon nanotube organic solar cell in this work shows a power conversion efficiency of 6.04%. This value is 83% of the leading ITO-based device performance (7.48%). Flexible application shows 3.91% efficiency and is capable of withstanding a severe cyclic flex test. © 2015 American Chemical Society. Source

Cui K.,University of Tokyo | Anisimov A.S.,Canatu Ltd. | Chiba T.,University of Tokyo | Fujii S.,Japan National Institute of Advanced Industrial Science and Technology | And 6 more authors.
Journal of Materials Chemistry A | Year: 2014

By using the excellent optical and electrical properties of pristine SWNTs with long bundle lengths, we present single-walled carbon nanotube-silicon (SWNT/Si) solar cells of 11% power conversion efficiency (PCE), prepared without doping. The PCEs of the fabricated solar cells even increased slightly after 10 months of exposure to ambient conditions, without any external protection. The open-circuit voltage of the SWNT/Si solar cells under low light intensities, down to 10 mW cm-2, demonstrated the characteristics of the ideal p-n junction model. The mechanism was discussed, taking into account the effect of varying the interfacial oxide layer thickness between the SWNTs and Si on the solar cell's performance. The high efficiency and stability demonstrated in this study make SWNT/Si solar cells one of practical choices for next generation energy system. © 2014 the Partner Organisations. Source

Gorkina A.L.,Skolkovo Institute of Science and Technology | Tsapenko A.P.,Skolkovo Institute of Science and Technology | Gilshteyn E.P.,Skolkovo Institute of Science and Technology | Koltsova T.S.,Polytechnic University of Mozambique | And 7 more authors.
Carbon | Year: 2016

Carbon nanomaterials (carbon nanotubes (CNTs) and graphene) are promising materials for optoelectronic applications, including flexible transparent and conductive films (TCFs) due to their extraordinary electrical, optical and mechanical properties. However, the performance of CNT- or graphene-only TCFs still needs to be improved. One way to enhance the optoelectrical properties of TCFs is to hybridize CNTs and graphene. This approach leads to creation of a novel material that exhibits better properties than its individual constituents. In this work, the novel hybrid CNT-graphene nanomaterial was fabricated by graphene oxide deposition on top of CNT films. The graphene oxide was then reduced by thermal annealing at ambient atmosphere or in H2 atmosphere. At the final step the CNT-graphene hybrids were chemically doped using gold(III) chloride. As a result, we show that the hybrids demonstrate excellent optoelectrical performance with the sheet resistance as low as 73 Ω/□ at 90% transmittance. © 2016 Elsevier Ltd. Source

Reynaud O.,Aalto University | Nasibulin A.G.,Aalto University | Nasibulin A.G.,Skolkovo Institute of Science and Technology | Anisimov A.S.,Canatu Ltd. | And 3 more authors.
Chemical Engineering Journal | Year: 2014

A mixture of single-walled and double-walled carbon nanotubes (CNTs) was synthesised by an aerosol CVD (floating catalyst) method for fabrication of highly conductive and transparent films. The feedstock solution contained ferrocene as a catalyst particle precursor, toluene and ethylene as carbon sources and thiophene as a promoter was introduced in the reactor in a hydrogen atmosphere and heated up in the temperature range of 1000-1200. °C. The product was collected downstream of the reactor by filtering the flow in the form of thin films with adjustable thicknesses (transmittance) and subsequently transferred on a desirable substrate by a dry transfer technique. This method allowed us to fabricate excellent quality CNT films with a high optoelectronic performance: with a sheet resistance of 86. Ω/sq. at the transmittance of T= 90%. To our best knowledge, for the first time the CNT transparent and conductive thin films were fabricated from direct filtration of gas phase grown CNTs using hydrocarbon as a carbon source. © 2014 Elsevier B.V. Source

Nasibulin A.G.,Aalto University | Kaskela A.,Aalto University | Mustonen K.,Aalto University | Anisimov A.S.,Aalto University | And 11 more authors.
ACS Nano | Year: 2011

We report a simple and rapid method to prepare multifunctional free-standing single-walled carbon nanotube (SWCNT) films with variable thicknesses ranging from a submonolayer to a few micrometers having outstanding properties for a broad range of exceptionally performing devices. We have fabricated state-of-the-art key components from the same single component multifunctional SWCNT material for several high-impact application areas: high efficiency nanoparticle filters with a figure of merit of 147 Pa-1, transparent and conductive electrodes with a sheet resistance of 84 ω/ and a transmittance of 90%, electrochemical sensors with extremely low detection limits below 100 nM, and polymer-free saturable absorbers for ultrafast femtosecond lasers. Furthermore, the films are demonstrated as the main components in gas flowmeters, gas heaters, and transparent thermoacoustic loudspeakers. © 2011 American Chemical Society. Source

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