Preparation and characterization of Co and Ga2O3-codoped ZnS and ZnSe bulk ceramics

Abstract

The bulk ceramics (Co)_x(Ga₂O₃)_0.6−x(ZnS/Se)_0.4 (x = 0.1, 0.3 and 0.5) were fabricated via a solid state reaction in a high temperature pipe boiler at temperatures ranging from 1000 to 1400 °C. The structure, optical, valence and morphological properties were determined by XRD, XPS, Raman spectroscopy, SEM, UV-vis spectroscopy and IR absorption spectroscopy. The impressive effect of the sintering temperature on the doping elements was investigated, and the optimum sintering temperature in the range 1000–1200 °C was revealed, by analysis of the mass loss, molar ratio and shrinkage rate of (Co)_x(Ga₂O₃)_0.6−x(ZnS/Se)_0.4. The zinc-blende structure of the bulk ceramic, and optimum doping ratio of (Co)_0.5(Ga₂O₃)_0.1(ZnS/Se)_0.4, was confirmed by XRD and Raman spectroscopy. A broad and continuous absorption band from visible to infrared wavelengths was demonstrated for (Co)_0.5(Ga₂O₃)_0.1(ZnS/Se)_0.4. The +2 and +3 valences of Co and Ga in the materials was proved by XPS. The surface morphology of the films was visualised by SEM and exhibited excellence when sintering temperatures were in the range 1000–1200 °C. The bulk ceramics (Co)_x(Ga₂O₃)_0.6−x(ZnS/Se)_0.4 show a promising potential for future applications.