Flexible Counter Electrodes Based on Mesoporous Carbon Aerogel for High-Performance Dye-Sensitized Solar Cells

Flexible counter electrodes (CEs) are designed and fabricated by depositing the composite film of carbon materials (carbon aerogel, carbon black, and active carbon) and poly(tetrafluoroethylene) on stainless steel mesh and applied in dye-sensitized solar cells (DSSCs). The effect of pore structure of the carbon materials on the electrocatalytic activity was investigated by cyclic voltammogram and electrochemical impedance spectroscopic analysis. The carbon aerogel with a mesopore structure showed the highest double-layer capacitance and best electrocatalytic activity. The DSSC, based on the carbon aerogel CE and a ruthenium dye (N719), showed a high power conversion efficiency of 9.06%, which is 99% of that based on a Pt CE (9.14%) under the same experimental conditions.