DNA assembled single-walled carbon nanotube nanocomposites for high efficiency dye-sensitized solar cells

Abstract

The performances of photovoltaic devices can be improved by using high electron mobility nanocomposites to increase charge collection and transportation. Single-walled carbon nanotubes (SWNTs) exhibit high electron mobility and are believed to be promising materials to enhance the power conversion efficiency of photovoltaic devices. Herein, we present DNA applied as a biological scaffold to fabricate SWNTs/TiO₂ and SWNTs/TiO₂/Ag nanocomposites, which are integrated into photoanode films to achieve high efficiency dye-sensitized solar cells (DSSCs). The effects of the amounts of SWNTs and Ag NPs in photoanode films on the performances of DSSCs are investigated. After incorporating the nanocomposites into photoanode films, the power conversion efficiency is enhanced. In particular, when the amounts of SWNTs and Ag NPs in the photoanode are 0.15 wt% and 0.8 wt%, the DSSC exhibits a high power conversion efficiency of ∼5.99%, ∼37.07% improvement compared with conventional TiO₂-only DSSCs. The mechanisms of the performance improvement are discussed in detail.