Metal and Metal Oxide Interaction in Hollow CuO/Pd Catalyst Boosting Ethanol Electrooxidation

Abstract

A low Pd-loaded lychee-nut-like catalysts of CuO/Pd with hollow nanostructure are prepared by electrochemical displacement reaction, in which a Cu2O mesoporous sphere is as a sacrificial template in the presence of triblock copolymers Pluronic P123 (EO20PO70EO20). Furthermore, the feeding molar ratio of Cu2O and Na2PdCl4 is found to be critical factor for preparing well-defined hollow lychee-nut-like (HLN) CuO/Pd. Morphology, composition and crystal structure of the optimal HLN CuO/Pd catalysts are sufficiently characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy. The as-synthesized HLN CuO/Pd catalysts show high catalytic activity for ethanol oxidation in alkaline medium and the catalytic mass activity of the HLN CuO/Pd is 5.9-fold of commercial Pd/C and 10.8-fold of Pd black. In turn, HLN CuO/Pd catalysts possess outstanding stability and superior tolerance to CO species. The remarkably electrochemical catalysis performance of HLN CuO/Pd catalysts is attributed to the unique lychee-nut–like open nanostructures and the mutual interaction between Pd and CuO support, which optimizing the electronic structure.