Green, Multi-Gram One-Step Synthesis of Core-Shell Nanocomposites in Water and Their Catalytic Application to Chemoselective Hydrogenations.

We devise a new and green route for the multi-gram synthesis of core-shell nanoparticles (NPs) in one step under organic-free and pH-neutral conditions. Simply mixing core and shell metal precursors in the presence of solid metal oxides in water allowed for the facile fabrication of small CeO2 -covered Au and Ag nanoparticles dispersed on metal oxides in one step. The CeO2 -covered Au nanoparticles acted as a highly efficient and reusable catalyst for a series of chemoselective hydrogenations, while retaining C=C bonds in diverse substrates. Consequently, higher environmental compatibility and more efficient energy savings were achieved across the entire process, including catalyst preparation, reaction, separation, and reuse.