Effect of CdSe thickness deposited by electrophoretic deposition for quantum-dot-sensitized solar cell

Abstract

Abstract Cadmium selenide (CdSe) and titanium dioxide (TiO2) nanoparticles in chloroform were deposited on fluorine-doped tin oxide (FTO) conducting glass-substrate by the electrophoretic deposition (EPD) method at varying voltages and deposition times. Firstly, TiO2 nanoparticles were deposited on FTO conducting glass-substrate at 150 V for 30 s by EPD method. The TiO2 films were then heated at 450°C for 3 h. After that, CdSe was deposited on TiO2 layer at 100 V for 60 s, 90 s, and 120 s by EPD method. The CdSe/TiO2 films were characterized using UV-visible spectroscopy (UV-vis) and scanning electron microscope (SEM). A complete quantum-dots-sensitized solar cells (QDSSCs) were assembled using polysulfide electrolyte and Cu2S counter electrodes. Polysulfide electrolyte was prepared with mixture of sulphur, sodium sulphide, sodium hydroxide and methanol/deionized water. The power conversion efficiency of 2% was achieved using a CdSe/TiO2 (100 V, 120 s) electrode, under simulated AM 1.5, 100 mW cm-2 illumination.