Recent progress on earth abundant electrocatalysts for oxygen evolution reaction (OER) in alkaline medium to achieve efficient water splitting - A review

Developing earth-abundant-electrocatalysts for oxygen evolution reaction is one of the promising ways to achieve efficient water-splitting for hydrogen production (a clean chemical fuel). This paper reviews the activity, stability and durability for oxygen evolution reaction in alkaline medium of different types of recently reported electrocatalysts such as Ni, Co, NiCo, Fe, Se, Mo, Cu, Mn, Zn, V, Ti/Ta, and metal free based earth-abundant-electrocatalysts. Further, this paper reviews the strategies used to achieve the remarkably low overpotential (including eta(10): <= 100 mV), high long term stability (including >= 100 h) and high durability (including >= 5000 cycles) of earth-abundant-electrocatalysts for oxygen evolution reaction in alkaline medium and those are better or well comparable with the state-of-the-art IrO2 electrocatalyst(2). Finally, this paper summarizes the efficient strategies such as preparing porous or nanostructured materials, preparing quantum sized materials, doping metals or heteroatoms, tuning the optimal crystal structure, preparing bimetallic/multi-metallic materials, preparing materials with oxygen vacancies/defects, preparing amorphous materials, preparing metal chalcogenides, preparing metal oxy hydroxides, and integrating electrocatalysts with carbon to enhance the activity, stability, and durability for OER.