In Situ Growth of Co_0.85Se and Ni_0.85Se on Conductive Substrates as High-Performance Counter Electrodes for Dye-Sensitized Solar Cells

Abstract

We present herein a facile one-step low-temperature hydrothermal approach for in situ growth of metal selenides (Co(0.85)Se and Ni(0.85)Se) on conductive glass substrates. The as-prepared metal selenides on conductive substrates can be used directly as transparent counter electrodes for dye-sensitized solar cells (DSSCs) without any post-treatments. It is found that graphene-like Co(0.85)Se exhibits higher electrocatalytic activity than Pt for the reduction of triiodide. As a consequence, the DSSC with Co(0.85)Se generates higher short-circuit photocurrent and power conversion efficiency (9.40%) than that with Pt.