Facile preparation of nanocrystalline TiO2 thin films using electrophoretic deposition for enhancing photoelectrochemical water splitting response

Titanium oxide (TiO2) nanocrystalline particles have been successfully deposited on fluorine-doped tin oxide (FTO) glass using an electrophoretic deposition (EPD) with a good uniformity. This study aims to optimize the heat treatment temperature, applied electric field, and deposition time to produce a good uniformity nanocrystalline TiO2 layer coating on FTO glass for better photoelectrochemical water splitting hydrogen generation performance under UV irradiation. In the present study, EPD technique allows controlling of TiO2 nanocrystalline layer characteristics on FTO glass, including smoothness and thickness. Characterisation like FE-SEM revealed that nanocrystalline TiO2 with a 14.6 μm thickness with good uniformity and minimal cracking surface exhibited the highest photocurrent density (2.12 mA/cm2) among samples. Besides, Raman and XRD analyses showed that nanocrystalline TiO2 thin coating form successfully. Based on our experiments, we proposed that the optimum condition to form nanocrystalline TiO2 thin film layer using EPD technique is 30 V, 60 s of deposition and post-annealing of the thin film at 400 °C based on the jp–V characteristic. Under illumination of 100 W UV light, the photoconversion efficiency can be up to 2.49%. In addition, hydrogen production was tested with the production rate is up to 0.45 mL/cm2/h and the photoelectrode can be re-used and remained stable for five cycles continuously.