▎ 摘　　要

The electrooxidation of ethanol in alkaline media by palladium (Pd) nanoparticles supported on 3D-Graphene nanosheets with varying morphological and physicochemical properties was investigated using potentiodynamic and potentiostatic techniques. 30 wt.% Pd electrocatalysts were synthesized using a surfactant -free soft alcohol reduction method (SARM) and deposited on thermally (7 at.% H2, 800 degrees C) and chemically reduced (N(2)FI(4)rxH(2)O, 80 degrees C) 3D-Graphene nanosheets. The morphology of the nanosheets was modified using silica (L90 and EH5) sacrificial templates. For the sake of comparison, Pd nanoparticles were also deposited on a commercial carbon support (Vulcan) using SARM and physically characterized using X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). The morphological and physicochemical properties of the 3D-Graphene supports were analyzed using Scanning Electron Microscopy (SEM), Nitrogen-sorption Brunauer-Emmett-Teller (BET), Energy dispersive X-ray Spectroscopy (EDS) and Raman Spectroscopy. Our results show that thermally reduced 3D-Graphene nanosheets with a higher the degree of C-C sp2 hybridization improved the dispersion and reduced the average crystallite size of the Pd nanoparticles. Moreover, Pd nanoparticles supported on 3D-Graphene nanosheets modified with larger silica templates (L90) showed better tolerance towards poisoning species, possibly due to the larger pores etched into its matrix. Among the as-prepared catalysts, Pd nanoparticles of 6.3 nm supported on thermally reduced 3D-Graphene (BET surface area of 300 m(2) g (1)) exhibited the highest stability as well as peak current density of 1568 Ag (11, which was about 1.5, 2.5 and 3 times greater than Pd nanoparticles supported on chemically reduced 3D-Graphene, Vulcan and commercial Pt/C catalysts respectively. (C) 2016 Elsevier Ltd. All rights reserved.