Design and Application of Hollow Flower-like Trimetallic Nanocrystals in Real-Time Catalytic Process Analysis

Hollow flower-like multi-metallic nanocrystals have attracted significant research attention due to their exceptional catalytic properties, which stem from their high surface area-to-volume ratio and abundant active sites. Nevertheless, conventional synthesis methods for noble metal nanocrystals typically involve complex procedures or require harsh reaction conditions. In this work, we developed a facile and environmentally benign strategy for fabricating hollow flower-shaped trimetallic nanocrystals at ambient temperature. Our approach employs AgCl nanocubes, derived from AgNO3 and HAuCl4, as self-sacrificing templates. Through ascorbic acid-mediated reduction of metal precursors, we successfully synthesized three distinct types of hollow flower-like nanocrystals: AuAgCu, AuAgPt, and AuAgPd. Comprehensive characterization confirmed the well-defined morphology and precise composition control of the as-prepared nanocrystals. The catalytic performance was systematically evaluated through in situ UV–vis spectroscopy monitoring of 4-nitrophenylthiophenol reduction, revealing the following activity trend: AuAgCu > AuAgPt > AuAgPd. This study not only provides a versatile platform for constructing sophisticated multi-metallic nanostructures but also offers valuable insights into the structure–activity relationship of complex catalysts.