Enhanced photocatalytic hydrogen generation and photostability of ZnO nanoparticles obtained via green synthesis

Abstract ZnO nanoparticles are prepared by green synthesis using Moringaoleifera natural extract. XRD and Raman analysis show crystalline ZnO with wurtzite structure. SEM and TEM images show the average size of the nanoparticles to be 100–200 nm. Photocatalytic generation of hydrogen by these nanoparticles has been investigated under UV–Visible light irradiation. Na 2 S and Na 2 SO 3 sacrificial agents dispersed with the photocatalyst are employed as hole scavengers. ZnO nanoparticles with smaller size shows better H 2 evolution rates up to 360 μmol hg −1 . It is noteworthy that ZnO nanoparticles prepared via novel green synthesis exhibits oxygen vacancies and registers enhanced photocatalytic activity as well as good photostability.