Switching the Charge Transfer Competition into Cooperative Utilization in Simultaneously Excited Plasmonic Metal and Semiconductor Systems

Abstract Integrating plasmonic metals with semiconductors offers an effective strategy to enhance photocatalytic efficiency. However, when both components are excited, there are two charge transfer processes in opposite directions between them, significantly reducing the charge carrier density. How to resolve this issue to realize the cooperative utilization of charge carriers remains exclusively explored. Herein, a plasmonic metal‐semiconductor composite prototype is constructed using Au nanobipyramids (Au NBPs) and CdS nanosheets. When Au NBPs and CdS are both excited, the photoactivity of Au NBPs/CdS composites is deteriorated compared to excitation of CdS alone, owing to the charge competition of hot electron injection and Schottky‐junction effect. Notably, the introduction of PdAg nanoparticles into Au NBPS/CdS can reverse the photoactivity trend, particularly through spatially optimized engineering of PdAg locations. The presence of PdAg with optimized location attenuates the charge transfer competition by directing electrons toward PdAg instead of offsetting each other. Consequently, the hydrogen evolution rate of the optimal Au NBP‐tip PdAg/CdS composite reaches 13.74 mmol g −1 h −1 under visible‐near infrared irradiation, a 57% increase over visible light irradiation. This study provides an in‐depth exploration of the electron transfer behavior within plasmonic metal‐semiconductor composites and offers new insights into the design of advanced photocatalytic materials.