Rational design of amorphous CoS coupling with crystalline Ni3B toward efficient oxygen evolution reaction: Computation and experiment

Constructing amorphous/crystalline heterostructures has been viewed as an effective strategy to modulate the electronic structure and enrich the active sites for catalysts, resulting in efficient oxygen evolution reactions (OERs). Herein, the band structure, density of states, work function, and mechanical properties of Ni3B were investigated using first-principles calculations to evaluate its promising support for OER. As a result, the Ni3B is characterized by good electron conductivity, excellent mechanical strength, and structural stability, which suggests that it is very suitable for coupling with an amorphous catalyst. Consequently, crystalline Ni3B support was fabricated by the solid-solid reaction, followed by constructing with amorphous CoS via an electrodeposition approach. The optimal CoS/Ni3B heterostructure requires an overpotential of 273 mV to achieve a current density of 10 mA cm-2 in 1M KOH media. Furthermore, it maintains a desirable stability for 24 h under an elevated current density of 50 mA cm-2, outperforming the commercially available RuO2 catalyst. This investigation presents novel insights into the development of efficient and durable non-noble metal catalysts.