Tungsten carbide nanowalls as electrocatalyst for hydrogen evolution reaction: New approach to durability issue

Abstract

We report a new approach to the durability issue in tungsten carbide electrocatalyst for hydrogen evolution reaction (HER), in a form radically differing from that of the conventional nanoparticle approach: the WC nanowalls, bottom-up grown by a plasma-assisted deposition on Si wafer. The pristine nanowall was highly crystalline and its surface was smooth in atomic scale, which enabled a superior durability in HER environment: no oxidation occurred at prolonged cycling (10,000 cycles) in the HER environment, even without additional functionalization or modification. The electrochemical activity, as presented by Tafel slope and turnover frequency (TOF), was as excellent as those of the best data in the literature.