Carbon nanoparticle template assisted formation of mesoporous TiO2 photoanodes for quantum dot-sensitized solar cells

Abstract

While the power conversion efficiency (PCE) of quantum dot-sensitized solar cells (QDSSCs) is still far below their theoretical efficiency, we herein provide a method to improve the solar cell performance by using carbon nanoparticles as a template to construct TiO₂ mesoporous photoanodes. Carbon nanoparticles are obtained by microwave synthesis and are further mixed with TiO₂ nanoparticles as a paste, and the photoanodes are prepared by spin-coating followed by thermal treatment. In comparison to the photoanodes fabricated from pure TiO₂ nanoparticles, the performance of the cells that are prepared from the carbon nanoparticle template assisted mesoporous TiO₂ photoanodes show obvious improvement. The best performance is achieved with a carbon nanoparticle content of 15 wt% in the photoanode. A maximum PCE of 4.41% is achieved, giving a 35.3% enhancement in cell efficiency. Systematic investigations are carried out to reveal the role of the carbon nanoparticles in the photoanode performance and the corresponding mechanism is proposed.