(Photo)electrochemical investigations on spray deposited n-Sb2S3 thin film/polyiodide/C photoelectrochemical solar cells

Sb2S3 thin films have been prepared by spraying the mixture of non-aqueous equimolar solutions of antimony trichloride [SbCl3] and thiourea [CS(NH2)2] in acetic acid (glacial) onto fluorine doped tin oxide (FTO) coated glass substrates. The cell configuration n-Sb2S3/0.5M (KCl + KI) + 0.01M I2/C is used for studying the current–voltage (I–V) characteristics in dark and light, photovoltaic output, spectral response, photoresponse and photovoltaic rise and decay characteristics. The studies reveal that the Sb2S3 thin films are n-type in conductivity. Using the Butler model, the optical band gap and minority carrier diffusion length (LP) are found to be 1.73 eV and 0.033 μm, respectively. The junction quality factor in dark (nd) and light (nl), series and shunt resistance (Rs and Rsh), fill factor (FF) and efficiency (η) for the cell have been estimated. The measured FF and η of the cell are 59.5 and 0.30%, respectively. Annealing and etching are found to improve the photoelectrochemical performance of the PEC cell.