One-Pot Production of Pt–Ni Alloy Nanodendrites on Ceria Nanosheet Supporting Materials with High Electrocatalytic Performance Toward Methanol Oxidation and Oxygen Reduction

Abstract

To create better fuel cell catalysts, effective approaches to generate hybrid materials comprised of intimately connected metal nanocatalysts and nonstoichiometric metal oxides with finely regulated topologies are very desirable. The production of closely connected metal (PtNi alloy)–metal oxide (CeOx, ceria) hybrid nanostructures is reported here using a simple one-pot synthesis technique. Heating a mixed metal (Pt, Ni, and Ce) precursor solution in oleylamine/oleic acid resulted in well-defined PtNi/ceria hybrids, in which PtNi alloy nanodendrites with multiple branches are evenly spread over small-grained ceria nanosheets. The ceria nanosheets in the hybrids have a large number of oxygen vacancies and a high conductivity due to their small grain size. In comparison to carbon-supported counterparts and a commercial catalyst, the prepared PtNi/ceria hybrids exhibited outstanding electrocatalytic activity and stability for both methanol oxidation and oxygen reduction reactions, which can be attributed to the synergistic effects of the Ni component and ceria on the enhancement of the electrocatalytic function. The current technique will be used to create the best multicomponent catalysts for specific processes.