Zn2SiO4 Hollow Nanoparticles with Persistent Luminescence: Implications for Drug Loading

Here, we report a synthesis method of Zn2SiO4@SiO2 hollow nanoparticles with adjustable thickness. A core–shell structured coordination polymer (CP) @ silica precursor was constructed by encapsulating silica on the surface of the CP through surface adsorption induced self-assembly. Then, the ideal shapes and large hollow cavities were produced through high-temperature calcination, and the formation process of hollow spheres was studied. Thanks to the hollow structure of the material, it has excellent drug loading capacity. It is worth noting that the thickness of the silica shell can be modulated by adjusting reagent amounts, calcination temperature, and time. Furthermore, this method exhibits broad applicability and can be extended to the synthesis of other hollow metal oxide materials. Persistent luminescence (PresL) was achieved through a simple ion-doping strategy. Notably, the silica shell thickness was found to regulate luminescence performance, and its underlying mechanism was further explored. This study not only establishes a synthetic route for designing hollow-structured PersL materials, but also offers perspectives on regulating the structure–performance relationships in multiphase composite materials. We hope the methodology developed and luminescent properties observed in this study will inspire the development of other innovative architectures integrating both physiological compatibility and theranostic capabilities.