Interconnected Pd Nanowire Networks Stereoassembled on Biomass-Derived Porous Carbon Skeletons as Bifunctional Electrocatalysts for Efficient Methanol and Formic Acid Oxidation

Abstract

Although palladium (Pd)/carbon composites have been long regarded as key anode electrocatalysts for direct liquid fuel cells, the conventional particle-shaped Pd crystals as well as less porous carbon matrixes commonly render insufficient electrocatalytic efficiency. Here, we report a convenient and robust route to the bottom-up construction of one-dimensional (1D) interconnected Pd nanowire networks stereoassembled on wheat flour-derived three-dimensional (3D) Ndoped porous carbon skeletons (Pd/NPC) via a combined alkali-assisted thermal annealing and solvothermal process. This innovative design strategy is able to effectively harness the respective textural advantages of both ultrafine Pd nanocrystals and biomass-derived nanocarbons, resulting in a series of exceptional structural characteristics including 3D macroporous frameworks, large specific surface area, abundant N species, 1D cross-linked Pd nanowires, stable interfacial interaction, and high electron conductivity. Accordingly, the as-derived Pd/ NPC nanoarchitecture is capable to serve as a multifunctional electrocatalyst with large electrochemically active surface areas, high mass/specific activities, and dependable long-term durability toward both the methanol and formic acid oxidation reactions, which make it quite competitive against the traditional Pd/carbon black, Pd/carbon nanotube, and Pd/graphene catalysts with the same Pd loading content.