Performance Enhancement of Trimetallic Nanoparticles in Photocatalysis through Chemical Etching

Trimetallic nanoparticles have shown significant potential as multifunctional nanomaterials due to their superior photocatalytic performance, making them highly promising in materials science and nanotechnology. In this study, we designed and synthesized a trimetallic nanostructure consisting of a gold nanorod (Au NR) core, a silver (Ag) intermediate shell, and a silver-platinum (AgPt) alloy outer layer. The Au@Ag core-shell structure was first prepared by depositing silver onto the Au NR surface through a reduction reaction. Subsequently, an AgPt alloy was deposited via a reduction and replacement process, followed by oxidative etching to remove excess silver, resulting in the etched trimetallic nanostructure (Au@AgPt-E). Using methylene blue (MB) as the model system, the photocatalytic activity of Au@AgPt-E under visible and near-infrared light irradiation was significantly enhanced, achieving a rate 4.19 times higher than Au@Ag@AgPt and 7.67 times higher than single-metal Au NRs. The performance enhancement is primarily attributed to the surface plasmon resonance (SPR) effect of the Au NR core, which efficiently absorbs light energy and converts it into heat, facilitating the generation and separation of charge carriers. Additionally, the etching process increases the catalytic active sites on the AgPt surface. This study provides a novel approach for developing efficient plasmon-mediated photocatalysts and demonstrates broad application prospects in photocatalytic reduction processes.