Vanadium and nitrogen co-doped CoP nanoleaf array as pH-universal electrocatalyst for efficient hydrogen evolution

Exploring electrocatalysts which efficiently perform the hydrogen evolution reaction (HER) catalytic activity over wide pH range is greatly important for water splitting, however, remains enormous challenge. Herein, the host catalyst of CoP nanoarray on carbon cloth is co-doped with the guest elements of vanadium and nitrogen to acquire tuned electronic characteristics and additional active sites for improved HER activity. The electrochemical measurements show that the as-obtained V, N-CoP is endowed with smaller overpotentials and Tafel slopes than V-CoP and CoP. Impressively, V, N-CoP only needs low overpotentials of 57, 146, and 81 mV at 10 mA cm−2 in 1 M KOH, 1 M phosphate buffer, and 0.5 M H2SO4, respectively. This study sets a blueprint for developing pH-universal HER electrocatalysts via metal and nonmetal elements co-doping engineering.