Persistent luminescence and photocatalytic properties of Ga2O3:Cr3+,Zn2+ phosphors

• Compare the persistent luminescence of Ga2O3:Cr3+,Zn2+ and Ga2O3:Cr3+.
• Research the photocatalytic properties of Ga2O3:Cr3+,Zn2+ and Ga2O3:Cr3+.
• Discuss the relationship between the persistent luminescence and photocatalytic properties.

Ga2O3:Cr3+0.01, Zn2+0.005 and Ga2O3:Cr3+0.01 phosphors were synthesized by the high temperature solid state reaction. The emission and excitation spectra, persistent luminescence decay curve, thermoluminescence curve and photocatalytic properties were measured. The emission and excitation spectra indicate that the Zn2+ doping has no effect on photoluminescent properties of Ga2O3:Cr3+0.01. The red persistent luminescence of Ga2O3:Cr3+0.01, Zn2+0.005 could be observed for 20 min by naked eye. The thermoluminescence (TL) curve shows that a suitable trap was introduced into the Ga2O3:Cr3+ host by Zn2+ doping. The photocatalytic activity toward rhodamineB (RhB) was obtained to evaluate photocatalytic properties by Zn2+ doping. The results indicate that the Zn2+ doping could improve the photocatalytic properties of Ga2O3:Cr3+0.01 phosphors. It was considered that the new traps play an important role for trapping the electrons or holes to decrease the combination of the electrons and holes producing by the light irradiation and increase the photocatalytic activity.