Direct Observation of Hollow Bimetallic Nanoparticle Formation through Galvanic Replacement and Etching Reactions.
Wenhui WangIvan ErofeevYa HeFangqi YangHongwei YanJiong LuUtkur M MirsaidovPublished in: Nano letters (2023)
Hollow bimetallic nanoparticles (NPs) formed from metal oxide NP templates are widely used catalysts for hydrogen evolution and CO 2 reduction reactions. Despite their importance in catalysis, the details of how these NPs form on the NP templates remain unclear. Here, using in situ liquid-phase transmission electron microscopy (TEM) imaging, we describe the conversion of Cu 2 O template NPs to hollow PdCu NPs. Our observations show that a polycrystalline PdCu shell forms on the surface of the template via a galvanic replacement reaction while the template undergoes anisotropic etching. This study provides important insights into the synthesis of hollow metallic nanostructures from metal oxide templates.