Interconnected Pd Nanowire Networks Stereoassembled on Biomass-Derived Porous Carbon Skeletons as Bifunctional Electrocatalysts for Efficient Methanol and Formic Acid Oxidation
Zihan Zhu, Jinlong Qin, Qibin Yang, Haiyan He, Lu Yang, Huajie Huang, Guobing Ying
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) N-doped 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.