In-situ Grown Hybrid Nanocarbon Composite for Dye Sensitized Solar Cells

Abstract

Herein, a facile in-situ grown nanocarbon composite including one dimensional (1D) carbon nanotubes (CNTs) and two dimensional (2D) graphene nanosheets on FTO conductive glass substrates is used directly as a transparent counter electrode (CE) for dye sensitized solar cells (DSSCs) without any post-treatments. In the novel nano-composite, the CNTs without aggregations are not woven into each other, which is beneficial for the transport of carriers. Additionally, the 2D graphene between CNTs and the FTO conductive glass substrates is thought as the platform for accelerating the ballistic transport. It is found that the hybrid CNTs/graphene nano-composite exhibits relative high electrocatalytic activity for the reduction of triiodide. Besides, the design of bifacial DSSC with the hybrid transparent CNTs/graphene CE improves the utilization ratio of incident light. As a consequence, the bifacial DSSC with the optimized hybrid CNTs/graphene exhibits energy conversion efficiency (η) of 5.16% and 4.30%, corresponding to front- and rear-side illumination, respectively.