Electrospun TiC/C nano-felt surface-decorated with Pt nanoparticles as highly efficient and cost-effective counter electrode for dye-sensitized solar cells

Abstract

Electrospun nano-felt consisting of overlaid TiC/C composite nanofibers was surface-decorated with Pt nanoparticles (Pt NPs) for use as highly efficient and cost-effective counter electrode (CE) in dye-sensitized solar cells (DSSCs). In the nanofibers, the self-generated TiC crystallites (∼70 wt%) with sizes of ∼20 nm were randomly embedded in carbon (∼30 wt%). Upon surface-decoration, most Pt NPs were distributed on TiC crystallites, leading to substantial enhancement in the electrocatalytic activity/efficiency of Pt due to the strong interaction between Pt and TiC as well as the resulting synergetic effect on electrocatalysis. Electrochemical measurements indicated that the TiC/C–Pt CE exhibited low charge transfer resistance (R_ct), large capacitance (C), and fast reaction rate towards the reduction of I₃⁻ ions, and the prototype DSSC exhibited a performance comparable to that with conventional Pt CE in terms of short circuit current density (J_sc), open circuit voltage (V_oc), fill factor (FF), and energy conversion efficiency (η).