单一光催化剂容易出现可见光利用率低、电子空穴对失活及复合等问题，而经掺杂改性的复合光催化剂往往表现出更优良的效能。本文采用液相合成法制备得到一种以贵金属金（Au）为核，宽禁带的半导体二氧化錫（SnO₂）为外壳的Au@SnO₂核壳结构纳米材料。在532 nm可见光的照射下，Au@SnO₂核壳结构纳米粒子能够有效降解包括染料分子罗丹明B、亚甲基蓝以及抗生素四环素在内的有机化合物，表現出较好的光催化活性。此外，我们还讨论了Au@SnO₂核壳纳米颗粒的光催化机制。当前的研究结果可为核壳结构纳米材料的合成以及光催化技术的发展提供借鉴，并为旨在解决水污染问题的环保行业提供一些参考方向。

Single photocatalysts usually have the following shortcomings such as low utilization of visible light, deactivation and recombination of electron-hole pairs, while composite photocatalysts modified by doping tend to show better performance. In this thesis, liquid-phase synthesis method is used to prepare Au@SnO₂ core-shell nanomaterial, a new composite material with the noble metal gold (Au) as the core and the band gap semiconductor SnO₂ as the shell, which exhibits excellently photocatalytic activity in the later experiments. Upon the irradiation of 532 nm visible light, Au@SnO₂ core-shell structured nanoparticles can effectively degrade the organic compounds, including the dye molecules rhodamine B, methylene blue and antibiotic tetracycline. In addition, the photocatalytic mechanisms of Au@SnO₂ core-shell nanoparticles are also discussed. These results can provide some useful information on the synthesis of core-shell nanomaterials and the development of photocatalytic technology, as well as directions for the environmental protection industry aimed at solving water pollution.