Fabrication of dendritic PdCu alloy supported on 3D N-doped hollow graphene for efficient ethanol electrooxidation

Fabricating highly efficient Pd-based nanocatalysts with a well-defined structure is desired for the commercialization of direct ethanol fuel cell (DEFC). Herein, series hierarchical three-dimensional N-doped hollow graphene spheres (NHGS) supported dendritic PdCu alloy catalysts Pd$_{x}$Cu$_{(d)}$-NHGS (x: Cu/Pd theoretical molar ratio 4, 2, and 1) are assembled by one-pot ascorbic acid reduction-immobilization method. Aiming to maximize Pd utilization realize electrooxidation, this novel electrocatalyst offers potent activity sites promotes electron ion kinetics simultaneously. Characterization indicates that as-obtained Pd$_{4}$Cu$_{(d)}$ nanoparticles average sizes approximately 55 nm evenly dispersed on NHGS supporting materials obtained using SiO2 nanospheres template strategy. Three all exhibit enhanced electrocatalytic activity, which Pd$_{4}$Cu$_{(d)}$-NHGS shows highest mass current (2683 mA mg$_{Pd}$$^{-1}$), 2.59 times commercial Pd/C toward electrooxidation in alkaline medium. Based results, we believed could extensive application prospect DEFC. Key words: