Enhancement on Charge Generation and Transfer Properties of Sb2S3 Quantum-Dot-Sensitized Solar Cells by ZnO Nanorods Optimization

Abstract

ZnO nanorod films prepared using different electrochemical deposition processes have been employed as photoelectrodes for Sb2S3 quantum-dot-sensitized solar cells. The density and diameter of the ZnO nanorods were adjusted by varying the electrochemical deposition time. The optical absorption and photoluminescence spectra of the different Sb2S3-sensitized ZnO nanorod photoelectrodes were investigated, revealing that the best optical absorption and charge separation properties were exhibited by the Sb2S3-sensitized ZnO nanorod photoelectrodes obtained using an electrochemical deposition time of 120 min. The charge transfer property of the quantum-dot-sensitized solar cells was also optimized by using ZnO nanorods with different structures. The Sb2S3-based quantum-dot-sensitized solar cells based on the ZnO nanorod photoelectrodes with relatively high density and low diameter fabricated using a deposition time of 120 min exhibited excellent charge generation and transfer properties, enabling higher current density and thereby a photovoltaic power conversion efficiency of 2.04%.