Electropolymerization of Aniline on Nickel-Based Electrocatalysts Substantially Enhances Their Performance for Hydrogen Evolution

Extensive efforts have been devoted to developing competent electrocatalysts for hydrogen evolution reaction (HER). However, limited attention has been devoted to exploring the benefits of conductive polymers to improve the performance of various HER electrocatalysts. Herein, we demonstrate that electropolymerization of aniline on nickel foam (PANI/Ni/NF) dramatically increases the latter's HER performance from pH 14 to 0. For instance, in alkaline electrolyte, PANI/Ni/NF achieved the current density of -10 mA cm(-2) at an overpotential of merely 72 mV, similar to 100 mV less than that of the pristine nickel foam. We further demonstrate that such a layer can also boost the HER performance of nickel phosphides and sulfides, highlighting the great versatility of PANI in improving the HER activities of various low-cost electrocatalysts.