Amorphous aerogel of trimetallic FeCoNi alloy for highly efficient oxygen evolution

Abstract Developing highly efficient, cost-effective and extremely stable electrocatalysts toward oxygen evolution reaction (OER) is a great challenge for their promising water splitting application to promote the sluggish kinetics. In this work, an amorphous non-noble FeCoNi trimetallic aerogel (FeCoNi AG) is prepared via a one-step in situ spontaneous gelation and reduction strategy, presenting a remarkable OER activity and stability in an alkaline medium. FeCoNi AG catalyst delivers an exceptionally low overpotential of 235 mV at a current density of 10 mA cm−2 and features a small Tafel slope of 50 mV dec-1 in 1 M KOH, which is superior to the state-of-the-art RuO2 and many other reported transition FeCoNi-based catalysts. In addition, an outstanding long-term durability during 40 h chronoamperometric test and 5000 cyclic voltammetry (CV) cycles without obvious degradation of current density is achieved. This work is of high inspiration for developing transition metals-based amorphous aerogel electrocatalysts for greatly enhanced oxygen evolution.