Crystal interpenetration featured NiWSe@NF acicular nanowires for performance enhanced water splitting

Abstract

Synergistic composite catalysts have always been the research focus of water splitting. Whereas, amorphous phases usually occurred on grain boundaries, which greatly hinders electron transfer and reduces the catalytic performance. Herein, a NiWSe@NF acicular nanowire electrode was fabricated by a simple hydrothermal strategy, affording outstanding activity and durability, requiring overpotentials of only 103 mV (HER) and 203 mV (OER) under 10 mA cm−2, respectively. Experimental studies and theoretical analysis demonstrate that the excellent catalytic activity is attributed to the interpenetrate structure, which eliminates the formation of amorphous phase and provides a high-speed channel for electron transmission. The crystal interpenetration on grain boundaries adjusts the electronic, promotes the intermediates adsorption and reduce reaction energy barrier. The super-hydrophilic arisen from crystal interpenetration would also reduce the adhesion of generated bubbles and avoid performance attenuation. This work provides a new perspective for the development of high-efficiency composite catalysts.