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The modifications of local structure in solid solution are a crucial step to regulate the photoluminescence properties of rare-earth ion-based phosphors. However, the structural diversity of host matrices and the uncertain occupation of activators make it challenging to obtain phosphors with both high stability and tailored emission. Herein, We synthesized a series of β-Ca3(PO4)2-type Ca8ZnGa(1–x)La x (PO4)7:Eu2+ solid solution phosphors by design. By modifying the Ga/La ratio, controllable regulation of the emission spectrum and thermal stability of the phosphors can be achieved at the same time. The introduction of La3+ can regulate the crystal field splitting strength of the Eu2+ activators, causing redshifts in the emission spectrum while increasing Ga3+ content will lead to enhanced energy transfer between the oxygen vacancy and Eu2+, as well as improved thermal stability. Through local structure modification, the spectrum and thermal stability of phosphors can be facilely tuned. The results indicate that this series of phosphors have versatile potentials in various applications.

The long-afterglow luminescent material Sr 2 MgSi 2 O 7 :(Eu, Dy) was combined with the photocatalytic material g-C 3 N 4 to construct a type of Sr 2 MgSi 2 O 7 : (Eu, Dy)/g-C 3 N 4 self-luminous photocatalytic composite. This overcomes the limitation that photocatalytic experiments can only be carried out under an external light source, and it provides a more flexible way to use photocatalytic technology in environmental purification. The morphology, structure, luminescence, and photocatalytic properties of the samples were investigated using a variety of advanced characterization techniques. The results show that the significant improvement in the photocatalytic performance is attributed to the formation of a Z-scheme heterojunction between the luminescent and photocatalytic materials and the promotion of the photocatalytic reaction by the properties of the long-afterglow luminescent material itself. A possible mechanism for the photocatalytic process of the composite is proposed, and it is speculated that the reason for the increased photocatalytic activity is internal electron transfer and electron−hole pair separation based on tests such as X-ray photoelectron spectroscopy and density functional theory calculations. This study provides a strategy for enhancing the photocatalytic activity of photocatalysts and achieving round-the-clock degradation of pollutants.

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