Small angle X-ray scattering and photoluminescence study of ZnO nanoparticles synthesized by hydrothermal process

Polydisperse ZnO nanoparticles have been synthesized by a hydrothermal process. Small-angle X-ray Scattering (SAXS) was performed for particle size distribution analysis of ZnO nanoparticles. Room-temperature photoluminescence measurements revealed that the ZnO nanoparticles have a single visible emission peak ∼600 nm, although polydispersity of the sample shows no presence on PL spectrum. It seems the orange emission ∼600 nm is due to the presence of Zn(OH)2 on the surface of ZnO nanoparticles, instead of the commonly assumed interstitial oxygen defect.