Investigating the preparation parameters during the synthesis of CuInS2 thin film photoelectrodes

Effects of electrodeposition time during the n-type CuInS₂ thin film electrodes synthesis was studied in this work. All the CuInS₂ thin film were fabricated via a single-step electrodeposition of Cu/In/S precursors on a transparent fluorine-doped tin oxide (FTO) substrate and calcined in a reducing gas atmosphere at 500 °C without using the toxic H₂S gas for sulfurization. Thirty minute deposition time was the optimum condition based on the morphological features observed in the scanning electron microscope (SEM) images and the highest anodic photocurrent generated upon visible light illumination in the photoelectrochemical (PEC) test. The optical properties characterization revealed the CuInS₂ thin films to have a direct bandgap of 1.42 eV, which confirmed the visible light active properties in the PEC performance.