Unique heterointerface engineering of Ni2P−MnP nanosheets coupled Co2P nanoflowers as hierarchical dual-functional electrocatalyst for highly proficient overall water-splitting

A noble-metal-free electrocatalyst comprised of hybrid Ni2P−MnP nanosheet coupled with Co2P nanoflowers (Ni2P−MnP@Co2P) reinforced on nickel foam has been achieved with a unique heterostructure architecture for highly competent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Tri-phased Ni2P−MnP@Co2P nanocrystal offers tremendously active and robust electrocatalytic efficacy heralded by low HER (60 mV) and OER (255 mV) to achieve (10 and 30) mA cm−2 current densities, respectively. The outstanding electrochemical performance is due to the distinctive architectural feature, high surface area with optimum porosity, bountiful Ni2P−MnP and Co2P heterointerface interaction, and synergism among Ni2P, MnP, and Co2P multi-active sites. The Ni2P−MnP@Co2P (+,−) alkaline electrolyzer delivers a low cell voltage of 1.50 V at a current density of 10 mA cm−2, along with astonishing long-term robustness. Moreover, the electrocatalyst displays a Faradaic yield of around (97.2 and 97.9) % at 50 mA cm−2 for H2 and O2 respectively. This work is expected to pave the way for novel insights into the fabrication of efficient electrocatalysts for practical water-splitting applications.