▎ 摘　　要

In this study, graphene nanosheets (GNs) were used to fabricate novel counter electrodes (CEs) for dye-sensitized solar cells (DSSCs). The electrode properties of various CEs were comprehensively analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectrometry (EDS), and cyclic voltammetry (CV). DSSCs with various GN CEs were characterized using current density-voltage (J-V), incident photo-to-current conversion efficiency (IPCE), and electrochemical impedance spectroscopy (EIS) measurements. The results show that GN CEs sintered at 400 degrees C in a nitrogen atmosphere for 30 min yielded the optimal electrode properties and DSSC efficiency. This study also fabricated GN-Pt composite and GN-Pt stacked CEs for the DSSCs, and the influences of the CEs on the efficiency of the DSSCs were investigated. The results show that the GN-Pt stacked CEs yielded the optimal electrochemical catalytic properties and DSSC efficiency. The power conversion efficiency of the DSSCs based on GN-Pt stacked CEs yielded a 16.7% improvement compared with conventional Pt CEs. (C) 2014 Elsevier B.V. All rights reserved.