Effects of Ni(OH)₂ Morphology on the Catalytic Performance of Pd/Ni(OH)₂/Ni Foam Hybrid Catalyst toward Ethanol Electrooxidation

Abstract

Creating concerted active sites composed of noble metals and oxophilic metal hydroxides/oxides has proven to be an effective approach for improving the performance of the electrocatalysts toward ethanol oxidation. However, the effects of hydroxide morphology on the catalytic property have received very limited attention. Herein, we report the synthesis of a nickel foam (NF)-supported hybrid electrocatalyst by using a facile glucose-assisted hydrothermal method followed by an electrodeposition process. The resulting catalyst was composed of the grown Ni(OH)2 nanosheets on NF, the amorphous-like carbon resulting from hydrothermal carbonization of glucose and nanosized Pd. Our study found that the presence of glucose in the hydrothermal process resulted in a notable morphology change of Ni(OH)2 nanosheets, and the resulting hybrid catalyst exhibited remarkable property improvements in terms of electrocatalytic activity and long-term durability for ethanol oxidation reaction (EOR) in alkaline solutions. Our study highlights the important role of morphology control of hydroxide in the EOR electrocatalysis.