Investigating the Hybrid-Structure-Effect of CeO -Encapsulated Au Nanostructures on the Transfer Coupling of Nitrobenzene.

Due to the obvious distinctions in structure, core-shell nanostructures (CSNs) and yolk-shell nanostructures (YSNs) exhibit different catalytic behavior for specific organic reactions. In this work, two unique autoredox routes are developed to the fabrication of CeO -encapsulated Au nanocatalysts. Route A is the synthesis of well-defined CSNs by a one-step redox reaction. The process involves an interesting phenomenon in which Ce can act as a weak acid to inhibit the hydrolysis of Ce under the condition of OH shortage. Route B is the fabrication of monodispersed YSNs by a two-step redox reaction with amorphous Co O as an in situ template. Furthermore, the transfer coupling of nitrobenzene is chosen as a probe reaction to investigate their catalytic difference. The CSNs can gradually achieve the conversion of nitrobenzene into azoxybenzene, while the YSNs can rapidly convert nitrobenzene into azobenzene. The different catalytic results are mainly attributed to their structural distinctions.