Engineering of NiO/ZnO Core-Shell Nanostructure via Facile Chemical Processes for Environmental Application

Abstract

NiO/ZnO core–shell nanoflakes structures were successfully fabricated using a unique strategy consisting of a simple chemical bath deposition (CBD) route followed by a metal-organic chemical vapor deposition (MOCVD) technique with different growth times. The XRD results combined with Raman measurements and X-ray photoelectron spectroscopy confirmed that the surface property and photocatalytic activity of NiO/ZnO core–shell nanostructures affected by varying the growth time of ZnO on the surface of NiO nanoflakes. The Scanning electron microscopy images exhibited that the NiO/ZnO samples have a porous core–shell architecture with high surface area and abundant open sites, resulting in enhanced photocatalytic activity. The photocatalytic activity was tested for the prepared samples by measuring the degradation of crystal violet (CV) dye under ultraviolet irradiation. NiO/ZnO core–shell nanostructures deposited at 30 min exhibits higher photodegradation efficiency toward CV dye compared to NiO/ZnO core–shell deposited at 60 min and NiO nanoflakes standing alone. The enhanced photocatalytic activity is due to the formation of p–n heterojunction between ZnO and NiO with a high specific area and more active site of core–shell nanoflakes architecture. The obtained results in this research suggest a new strategy for the fabrication of highly efficient photocatalytic activity semiconducting metal oxide with core–shell.