A highly efficient dye-sensitized solar cell with a platinum nanoflowers counter electrode

Abstract

This study applied the pulse reversal electrodeposition (PRE) technique to deposit a platinum film having a nanoflowers (PtNFs) structure onto an indium tin oxide (ITO) glass. The physical characteristics and electro-catalytic abilities of the PtNF-CEs were analyzed by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) patterns, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). A double layer theory and a crystal facet formation mechanism are used to explain the catalytic abilities of the PtNFs. Scanning electron microscopy (SEM) images depict a dramatic transformation in the surface structure of the Pt clusters. The ITO glass with the PtNFs was used as the counter electrode (CE) of a dye-sensitized solar cell (DSSC). The DSSC assembled with the as-prepared PtNF-CE exhibits a high power conversion efficiency (η) of 7.74%, while the cell with an additional thin (2 nm) sputtered layer of platinum on the PtNF film shows much higher η of 8.13%, both at 1 sun conditions. The performances of the DSSCs are further substantiated by the data from electrochemical impedance spectroscopy (EIS) and UV-Vis reflectance spectra.