▎ 摘 要
Hierarchical hybrid of few-layer graphene (FLG)/tungsten monocarbide nanowires has been achieved by carbonization of metal tungsten nanowires under atmospheric pressure chemical vapor deposition. Morphology, structure, composition, element distribution, and surface microstructure variations of the hybrid nanostructure were characterized by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy, scanning transmission electron microscope energy dispersive X-ray spectroscopy (STEM-EDX) mapping, and Raman spectroscopy.The results indicate that the graphene nanosheets are made of FLG layers with good crystallinity and the nanowires can be characterized as single-phase tungsten monocarbide. In situ growth of the graphene layers on the. WC nanowires presents hierarchical architecture that exhibits notable electrocatalysis with enhanced methanol oxidation current and higher ratio of the forward anodic peak current density to the backward anodic peak current density (I-f/I-b). The methanol current and I-f/I-b ratio of the optimized hybrid is 5 times and 1.4 times as high as that of the pristine tungsten carbide, respectively. The obtained hierarchical hybrid exhibits great potential in direct methanol 'fuel cells and other electrocatalysis applications.