Charge optimization induces reconstruction via compounding Ni(OH)2 and CoP: a novel route to construct electrocatalysts for overall water-splitting

Abstract

Electrolytic water-splitting has the advantages of high efficiency, environmental friendliness, and sustainability. It is becoming a leading approach for producing hydrogen. In order to improve the efficiency of water-splitting, a bifunctional electrocatalyst with high performance is needed. Herein, we present a novel approach to construct a bifunctional electrocatalyst for overall water-splitting by compounding Ni(OH)₂ and CoP. This combination induced charge optimization, thereby leading to surface reconstruction. The nanocomposite displayed outstanding catalytic performance, benefiting from its more reactive surface area, improved conductivity and enhanced electrocatalytic activity. The resulting Ni(OH)₂/CoP electrocatalyst exhibited excellent catalytic performance, with low overpotentials of 266 mV at 50 mA cm⁻² for the OER and 71 mV at −10 mA cm⁻² for the HER, and required only 1.54 V to reach 10 mA cm⁻² in an overall water-splitting device, overtaking most of the recently reported Co- and Ni-based catalysts. This innovative strategy offers new directions for the design of efficient electrocatalysts.