Preparation of tungsten carbide-supported nano platinum catalyst and its electrocatalytic activity for hydrogen evolution

Using ammonium metatungstate (AMT) treated by spay drying as precursors, the tungsten carbides (WC) catalyst with meso-porosity was prepared by gas-solid reaction in the atmosphere of CH4/H-2. The WC-supported nano platinum (Pt) catalyst was prepared by impregnation. SEM and XRD results showed that the average diameter of the Pt particles which were well dispersed on the surface of Pt/WC, was about 13.5 nm. The electro-catalytic properties and chemical stability of the Pt/WC powder microelectrode (PME) for the hydrogen evolution reaction in acid solution were investigated using the electrochemical techniques of cyclic voltammetry and linear sweep voltammetry. The results showed that the Pt/WC-PME exhibited an attractive catalytic activity in hydrogen evolution with parameter a in Tafel equation was 0.292 V, and the exchange current density of hydrogen evolution was 4.42 mA (.) cm(-2). When the overpotential was 250 mV, the activation energy of hydrogen evolution was 26.20 kJ (.) mol(-1).