Enhanced Photovoltaic Performance of Nanowire Dye-Sensitized Solar Cells Based on Coaxial TiO2@TiO Heterostructures with a Cobalt(II/III) Redox Electrolyte
2013 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, Vol. 5, no 20, 9872-9877 p.Article in journal (Refereed) Published
The growth of a TiO shell at the surface of TiO2 nanowires (NWs) allowed us to improve the power conversion efficiency of NW-based dye-sensitized solar cells (DSCs) by a factor 2.5. TiO2@TiO core-shell NWs were obtained by a two-step process: First, rutile-phase TiO2 NWs were hydrothermally grown. Second, a hongquiite-phase TiO shell was electrochemically deposited at the surface of the TiO2 NWs. Bare TiO2 and heterojunction TiO2@TiO NW-based DSCs were obtained using a cobalt(II/III) redox electrolyte and LEG4 as the dye. With this electrolyte/dye combination, DSCs with outstanding V-oc values above 900 mV were systematically obtained. While TiO2@TiO NW-based DSCs had slightly lower V-oc values than bare TiO2 NW-based DSCs, they provided 3-fold higher photocurrents, overall reaching 2.5-fold higher power conversion efficiencies. The higher photocurrents were associated with the larger surface roughness and an enhanced charge-carrier separation/transfer at the NW/dye interface.
Place, publisher, year, edition, pages
2013. Vol. 5, no 20, 9872-9877 p.
hydrothermal deposition, electrochemical deposition, nanowires, TiO2, cobalt(II/III) electrolyte, dye-sensitized solar cells
IdentifiersURN: urn:nbn:se:uu:diva-211461DOI: 10.1021/am402344dISI: 000326212900002OAI: oai:DiVA.org:uu-211461DiVA: diva2:667156