Optical and photocatalytic properties of Corymbia citriodora leaf extract synthesized ZnS nanoparticles

•ZnS nanoparticles were first time synthesized using Corymbia citriodora leaf extract.•Quantum confinement effects was observed in biosynthesized ZnS nanoparticles.•Biosynthesized ZnS was used for photodegradation of methylene blue.

ZnS nanoparticles were biosynthesized via a green and simple method using Corymbia citriodora leaf extract as reducing and stabilizing agent. The biosynthesized ZnS nanoparticles were in the size range of 45 nm with a surface plasmon resonance band at 325 nm. XRD analysis revealed that the nanoparticles were in the sphalerite phase. Quantum confinement effects of biosynthesized ZnS nanoparticles were observed using photoluminescence spectroscopy. The photocatalytic activity of the ZnS nanoparticles has been investigated by degradation methylene blue under UV light irradiation. Due to the smaller size and excellent dispersicity, the biosynthesized ZnS nanoparticles showed a superior photocatalytic performance compared with that of chemical synthesize ZnS nanoparticles.