Structural, magnetic and optical properties of ZnO nanostructures converted from ZnS nanoparticles

•Phase change of cubic ZnS to hexagonal ZnO via heat treatment.•Band gap was found to decrease with increasing calcinations temperature.•ZnO samples have higher magnetic moment than ZnS.•Blocking Temperature of the samples is well above room temperature.•Maximum negative%MR with saturation value ∼38% was found for sample calcined at 600° C.

The present work concentrates on the synthesis of cubic ZnS and hexagonal ZnO semiconducting nanoparticle from same precursor via co-precipitation method. The phase conversion of ZnS to highly crystalline hexagonal ZnO was done by heat treatment. From the analysis of influence of calcination temperature on the structural, optical and vibrational properties of the samples, an optimum temperature was found for the total conversion of ZnS nanoparticles to ZnO. Role of quantum confinement due to finite size is evident from the blue shift of the fundamental absorption in UV–vis spectra only in the ZnS nanoparticles. The semiconducting nature of the prepared samples is confirmed from the UV–vis, PL study and transport study. From the magnetic and transport studies, pure ZnO phase was found to be more prone to magnetic field.

Graphical abstractThe phase conversion of ZnS to highly crystalline hexagonal ZnO was done by heat treatment.Figure optionsDownload full-size imageDownload as PowerPoint slide