Enhanced photoelectrochemical performance of nanoparticle ZnO photoanodes for water-splitting application

Abstract

Abstract In this paper, fabrication of ZnO nanoparticle photoanodes for water splitting application is presented. At first, metal zinc films have been deposited on bare fluorine-doped tin oxide glass substrates by thermal evaporation method with chamber pressure 0.05 mbar, source temperature 700 °C and source-substrate distance 3 cm for fabrication of the photoanodes. This deposited zinc films have been annealed at 500 °C for 2 h in atmosphere for obtaining ZnO films. The prepared ZnO films with deposition times (10, 20 and 30 min) are characterized and investigated to find out the photoelectrochemical properties and their suitability for splitting of water. It has been observed that all the ZnO films have high crystallinity wurtzite structure and uniformly distributed nanoparticles with the size of 32–58 nm. ZnO film with 20 min sample has smallest nanoparticles (32 nm) than the others. All the ZnO photoanodes have exhibited higher solar to hydrogen conversion efficiency (0.29–0.42%) than the other researchers data. Among them, ZnO with 20 min sample has been showed maximum efficiency of 0.64% for UV illumination and 0.42% for visible light illumination than the ZnO photoanodes prepared with other deposition times (10 and 30 min).