Photoelectrochemical cells based on nanocrystalline Sb2S3 thin films

Abstract

Metal chalcogenide thin films prepared by chemical methods are currently attracting considerable attention, as it is relatively inexpensive, simple, and convenient for large area deposition. Nanocrystalline Sb2S3 thin films of different thicknesses were deposited from solutions containing antimony chloride, tartaric acid, and thioacetamide maintained at a bath temperature of 6°C. These films were prepared for different deposition time periods. Uniform thin films having thicknesses up to 206nm were obtained on the fluorine doped tin oxide (FTO) coated glass substrates.The photoelectrochemical (PEC) cell configuration was n-Sb2S3|0.1M (NaOH–KI–I2)|C. From the current–voltage characteristics (I–V) and capacitance–voltage (C–V) plots, it is concluded that the films are of n-type conductivity. The photovoltaic output characteristics were used to calculate fill factor (ff) and solar conversion efficiency (η). The low value of n may be due to the high value of series resistance (Rs) and interface states in the cell, which are responsible for the recombination mechanism. The magnitude of bandgap energy of Sb2S3 photoelectrode estimated from spectral response of PEC cell agrees with the magnitude obtained from optical absorption of films. The grain size and thickness of Sb2S3 films were found to cause significant changes in the photovoltaic performance.