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

• The ZnGa2O4 was synthesized by H3BO3 assisted solid-state reaction method.
• The ZnGa2O4:B3+ lasting phosphors could be observed for 1 h by naked eyes.
• The role of H3BO3 improved the depth of the traps.
• The photocatalytic performance of the ZnGa2O4 was measure.

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 10 mol%. The samples exhibited a wide emission band peak at 423 nm and a narrow emission peak at 502 nm under ultraviolet excitation (254 nm). 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.