Au–Ag alloy nanoparticles with different cavity sizes have great potential for improving photocatalytic performance due to their tunable plasmon effect. In this study, galvanic replacement was combined with co-reduction with the reaction kinetics processes regulated to rapidly synthesize Au–Ag hollow alloy nanoparticles with tunable cavity sizes. The position of the localized surface plasmon resonance (LSPR) peak could be effectively adjusted between 490 nm and 713 nm by decreasing the cavity size of the Au–Ag hollow nanoparticles from 35 nm to 20 nm. The plasmon-enhanced photocatalytic H₂ evolution of alloy nanoparticles with different cavity sizes was investigated. Compared with pure P25 (TiO₂), intact and thin-shelled Au–Ag hollow nanoparticles (HNPs)-supported photocatalyst exhibited an increase in the photocatalytic H₂ evolution rate from 0.48 µmol h⁻¹ to 4 µmol h⁻¹ under full-spectrum irradiation. This improved photocatalytic performance was likely due to the plasmon-induced electromagnetic field effect, which caused strong photogenerated charge separation, rather than the generation of hot electrons.

具有不同腔尺寸的Au-Ag合金纳米粒子由于具有可调节的等离激元效应，具有改善光催化性能的巨大潜力。在这项研究中，电流置换与共还原相结合，其反应动力学过程被调节以快速合成具有可调腔尺寸的Au-Ag中空合金纳米颗粒。通过将Au-Ag空心纳米颗粒的腔尺寸从35 nm减小到20 nm，可以有效地在490 nm和713 nm之间调整局部表面等离子体共振（LSPR）峰的位置。研究了不同腔尺寸的合金纳米粒子的等离子体增强光催化H ₂演化。与纯P25（TiO ₂），完整且薄壳的Au-Ag空心纳米颗粒（HNPs）负载的光催化剂在全光谱照射下，其光催化H ₂释放速率从0.48 µmol h ^-1增加到4 µmol h ^-1。这种改善的光催化性能可能是由于等离激元引起的电磁场效应，该效应导致了强烈的光生电荷分离，而不是热电子的产生。