The photocatalytic reaction can carry out only under light irradiation, which limits the application of photocatalytic technology in the wastewater treatment and hydrogen production under no-light condition. In this study, Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ with unique luminescence property was combined with Ag₃PO₄ to construct a novel Z-scheme Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺/Ag₃PO₄ photocatalyst. The morphology, structure, luminescence and photoelectric properties of the prepared samples were investigated by various characterization techniques. Besides, some important influencing factors such as the mass ratios of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ and Ag₃PO₄, illumination times and cycling times were investigated. The results indicate that the Z-scheme Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺/Ag₃PO₄ photocatalyst with the best mass ratio (15:1) possesses superior photocatalytic activity. In addition, levofloxacin (LEV) is selected as the organic pollutant and the photocatalytic performance of the prepared samples were evaluated. The results show that the LEV degradation rate is 81.94 % and the hydrogen production reaches 491 μmol/g under simulated sunlight irradiation. The long-afterglow Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ material can continue to support the photocatalytic reaction even after the light is turned off. The final LEV degradation is 86.84 % and the final hydrogen production amount reaches 591 μmol/g after the external light is removed. Meanwhile, the process and possible mechanism of the round-the-clock photocatalytic LEV degradation with simultaneous hydrogen production were reported for the first time. This work cleverly uses the long-afterglow Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ material combined with Ag₃PO₄ to form a novel Z-scheme photocatalyst, which realizes the organic pollutant degradation with simultaneous hydrogen production under the sunlight or no external light conditions, providing a new strategy for the round-the-clock efficient utilization of the photocatalyst.
 

photocatalytic hydrogen production;photocatalytic degradation;Round-the-clock photocatalytic activity;Z-scheme photocatalyst