Synthesis of a hollow structured core-shell Au@CeO2-ZrO2 nanocatalyst and its excellent catalytic performance

We proposed a hard-templated and electrostatic attraction induced deposition method to prepare a hollow core-shell Au@CeO2-ZrO2 nanocatalyst with a high surface area, in which a 6-8 nm ultrathin layer composed of CeO2-ZrO2 nanocrystals is embedded with individual Au nanoparticles, forming a sub-10 nm core-shell-like structure. In this hollow core-shell nanocatalyst, the mobility and growth of Au nanoparticles can be well inhibited even at 700 degrees C. For two model reactions of the selective reduction of 4-nitrophenol and CO oxidation, this Au@CeO2-ZrO2 nanocatalyst shows good catalytic activity and stability, compared with Au/CeO2-ZrO2 prepared by the deposition-precipitation (DP) method. For the CO oxidation, the activity of Au@CeO2-ZrO2 can be well maintained after calcination at 700 degrees C, while negligible CO conversion is observed over DP-Au/CeO2-ZrO2. Further research shows that the improved catalytic performance of this hollow core-shell nanocatalyst can be attributed to the nanoscale core-shell structure, which effectively inhibits the migration and growth of the Au NPs, and maximizes the interface between the Au NPs and the CeO2-ZrO2.