The porous CeO2-CuxO Assembly Composed of Small-sized Particles with Optimized Electronic Structure for Effective Catalysis

Abstract

The reduction in size and regulation of the electronic structure are two promising approaches for achieving effective catalysis, yet their simultaneous regulation remains challenging. Here, we report the synthesis of porous CeO2-CuxO assembly composed of small-sized particles (below 10 nm) through the pyrolysis of a precursor containing glucose, Ce and Cu salts. The in-situ formed CeO2 can act as "spacers" to inhibit the aggregation and growth of CuxO, facilitating the formation of small-sized particles. The CeO2 can also regulate electronic structure of Cu-based components for the enhanced catalysis. The porous structure of the assembly show a large surface area, being advantageous for exposing catalytic sites. Typically, the reduction of 4-nitrophenolate (4-NP) to 4-aminophenol (4-AP) can be completed within 3 minutes at 25°C, with no significant change in the activity after 15 reuses, outperforming individual CuxO and most reported catalysts. Theoretical calculations indicate that the interface formed between CeO2 and Cu that is in-situ formed during the catalytic process can optimize the adsorption of key intermediates, thereby enhancing catalytic performance. The catalyst also shows good performance for the hydrogenation of a series of nitro compounds. The "spacers" function of CeO2 can extend to the synthesis of other composites (CeO2-NiO, Ce2O3-Co3O4 etc.)