Bimetallic polyoxometalate derived Co/WN composite as electrocatalyst for high-efficiency hydrogen evolution

Electrocatalytic hydrogen evolution reaction (HER) is a simple way to generate environment-friendly hydrogen energy. Due to the high price and low content, the wide application of noble metal-based electrocatalysts is limited. It is of great significance to study inexpensive, high-performance non-precious metal-based electrocatalysts. In this work, bimetallic nitride (Co/[email protected]) was successfully prepared through a one-step high-temperature calcination way using dicyandiamide (DCA), bimetallic polyoxometalates, and cobalt nitrate. Co/[email protected] exhibits outstanding catalytic performance with the same overpotentials of 143 mV in both alkaline and acidic media at 10 mA cm−2. The Tafel slopes are 90 mV dec−1 and 118 mV dec−1, respectively. Co/[email protected] exhibits good stability in acidic and alkaline solutions for up to 30 h. The splendid catalytic performance can be mainly ascribed to the synergistic effect between Co and WN. This work shows experimental guiding significance for preparing simple transition metal-based electrocatalysts.