Scalable processing hollow tungsten carbide spherical superstructure as an enhanced electrocatalyst for hydrogen evolution reaction over a wide pH range

Abstract Developing highly efficient hydrogen evolution reaction (HER) electrocatalysts is of scientific and industrial importance. We report a hollow WC electrocatalyst obtained through a scalable strategy which is a combination of spray drying method with a subsequent gas-solid carburization reaction by using ammonium metatungstate (AMT) as the precursor. The as-prepared hollow structured WC catalyst has an improved BET surface area and a pore volume in comparison with the normal bulky WC (B-WC) catalyst synthesized using the same procedure but without the spray drying treatment for the precursor, which provides the hollow WC (H-WC) electrode a highly efficient catalytic structure to drive the electrocatalytic reactions such as HER. The attractive catalytic activity of this materials is that it can catalyze the HER over a wide pH range. And the comprehensive electrochemical characterization show the H-WC superstructure has the promising potential to be well coupled with many pH-dependent oxygen evolution reaction (OER) electrocatalysts in acid, neutral, and alkaline electrolytes for an overall water splitting reaction to generate hydrogen and oxygen.