Synthesis of Tungsten Oxide Nanorods by the Controlling Precipitation Reaction: Application for Hydrogen Evolution Reaction on a WO_3 Nanorods/Carbon Nanotubes Composite Film Modified Electrode

摘要

Tungsten trioxide nanorods (WO_3) were prepared by controlling the precipitation reaction of sodium tungstate dehydrates solution and hydrothermal process. The synthesized tungsten trioxide nanorods have been characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), cyclic voltammetry (CV) and linear sweep voltammetry (LSV). Electrochemical activity for hydrogen evolution reaction (HER) on WO_3 nanorods / carbon nanotube (WO_3/CNT) composite electrocatalyst was first studied in acid solution (0.1 M H_2SO_4) at room temperature. The overall experimental results revealed that the electrocatalytic activity for HER on WO_3/CNT is two order magnitude higher than those obtained with WO_3 nanorods and is four times than in the case of commercial WO_3 in 0.1 M H_2SO_4. On the other hand, the kinetic reaction mechanisms were discussed on WO_3/CNT electrocata-lysts in acid solution for HER. However, the rate-determining step carries through Tafel reaction on commercial WO_3, CNT, WO_3 nanorods and WO_3/CNT electrocatalysts in acidic solution was introduced.