Fabricating core-shell WC@C/Pt structures and its enhanced performance for methanol electrooxidation

© 2017 Chinese Physical Society. The spray-dried spheres within a W/Pt multi-separation can be used to prepare discrete core-shell WC@C/Pt catalysts through a typical carburization production mechanism at 800 °C. In contrast with previous studies of the WC/Pt synthesis, the reaction observed here proceeds through an indirect annealing mechanism at 600 °C wherein species diffuse, thereby resulting in core-shell structure, and Pt nanoparticles were successfully dispersed in size/shape and randomly scattered across the in situ produced C spheres. Through direct carburization or at higher initial hydrochloroplatinic acid concentrations, however, complete reaction with core-shell spheres was not observed. Indirect carburization reduces the strain felt by the bonds featuring the larger WC particles and allows the motion of carbon around WC and Pt nanoparticles to be reserved, influencing the electrocatalytic performance and stability toward methanol oxidation.