Effect of H3BO3 on the persistent luminescence and photocatalytic properties of ZnGa2O4 phosphors

Abstract

The phosphor ZnGa2O4 was synthesized via H3BO3 assisted solid-state reaction method. The effect of H3BO3 on the crystal structure, photoluminescence, persistent luminescence, and photocatalytic properties of the phosphor was studied in detail. X-ray diffraction patterns indicated that a pure phase ZnGa2O4 could be achieved at the sintered temperature 1200°C adding H3BO3 of 10mol%. The samples exhibited a wide emission band peak at 423nm and a narrow emission peak at 502nm under ultraviolet excitation (254nm). Moreover, H3BO3 improved the persistent luminescence properties of ZnGa2O4 phosphor effectively because H3BO3 increased the electron traps and improved the depth of the traps. In addition, photocatalytic activity test shown that ZnGa2O4 phosphor with H3BO3 exhibited lower catalytic activities than the pure ZnGa2O4 for the degradation of Rhodamine B by the ultraviolet irradiation. The reason was that the particle size of the ZnGa2O4 phosphor became larger when the ZnGa2O4 was synthesized using H3BO3 as flux.