Synthesis and Characterization of Bi2S3 Deposited on TiO2 Nanotubes (TiO2NTAs) as Photoanode in the Tandem DSSC-PEC System for Hydrogen Evolution

TiO2NTAs is one of the most frequently used photoanodes. However, TiO2NTAs has a wide bandgap, so it is only active under UV light. Therefore, this study modified TiO2NTAs photoanode film to increase its efficiency. A simple method that successfully assists the Bi2S3 coating process on the surface of TiO2NTAs film is the Successive Ionic Layer Adsorption and Reaction (SILAR) method. In this research, modified Bi2S3 with TiO2NTAs was prepared using the SILAR method with variations of the number of synthesis cycles at 1, 2, 4, and 6. Based on the synthesis results, the number of deposition cycles greatly influences the performance of TiO2NTAs films. The synthesized TiO2NTAs/Bi2S3 results were characterized using SEM, XRD, FTIR, UV-Vis DRS, and photoelectrochemistry. The X-ray diffractogram showed that the composite compound was obtained successfully. The SEM images showed that Bi2S3 was deposited on the surface of the TiO2NTAs without blocking the nanotube holes. The constructed DSSC-PEC system could produce hydrogen with an STH (solar-to-hydrogen) efficiency of 0.02318% in an H-type reactor using anode irradiation for 6 hrs.