X-ray excited luminescence of Ga- and In-doped ZnO microrods by annealing treatment

Ga- and In-doped ZnO microrods were prepared by low temperature hydrothermal process, and the effect of annealing temperature on morphology, crystallization, photoluminescence and X-ray excited luminescence were deeply researched. The results showed that both Ga- and In-doped ZnO microrods were possessed of a good crystalline quality and exhibited an intense visible emission band with a blue-shift under X-ray excitation. This blue-shift of the visible luminescence could be ascribed to the different contributions of the defect emissions, i.e. the increase in the oxygen vacancy (VO) emission and the decrease of the oxygen interstitial (Oi) emission. Moreover, a strong ultraviolet luminescence was also obtained by further hydrogen annealing. It is expected that Ga- and In-doped microrods are promising candidates for development of fast and high-spatial-resolution X-ray imaging detectors.