Yolk‐Shell AuAgPt Alloy Nanostructures with Tunable Morphologies: Plasmon‐Enhanced Photothermal and Catalytic Properties

Herein, the preparation of AuAgPt alloy yolk‐shell nanostructures with tunable elemental compositions and morphologies by conducting the mild, successive galvanic replacement reaction (GRR) between Au@Ag core‐shell nanocubes and H2PtCl6 is reported. In particular, the resulting products can be featured with well‐defined cubic frames and the distribution of all the three metals over the whole particle, which is enabled by the unique “etching and regrowth” mechanism. Due to the strong absorbance in visible region, the current products exhibit superb performances in two localized surface plasmon resonance (LSPR)‐based applications, photothermal heat conversion, and plasmon‐enhanced catalytic reduction of 4‐nitrophenol (4‐NP). In particular, the optimized photothermal heat conversion efficiency and the apparent rate constant of photocatalytic 4‐NP reduction reach 12.9% and 0.155 min−1, respectively, for the sample AuAgPt‐6 and AuAgPt‐12, respectively. Herein the present study, a feasible strategy for fabrication of plasmonic‐active multimetallic alloy nanocrystals with yolk‐shell structure and cubic frame‐like edges is offered and their promising use in photothermal heat conversion and photocatalysis is validated, which could be extended to other alloys or material combinations for rational design of nanoscale materials with plasmon‐enhanced properties. Herein, AuAgPt alloy yolk‐shell nanostructures with tunable elemental compositions and morphologies by conducting the mild, successive galvanic replacement reaction (GRR) between Au@Ag core‐shell nanocubes and H2PtCl6 is reported, which exhibit plasmon‐enhanced activity in both photothermal conversion and catalytic reduction of 4‐NP.