Mesoporous manganese cobaltate: Colloid assisted ethylene glycol combustion synthesis and application in efficient water oxidation

Highlights: • A facile colloid ethylene glycol solution combustion strategy is developed to prepare mesoporous MnCo₂O₄. • The SSA of MnCo₂O₄ could reach up to 124.4 m²/g with hierarchical mesopores. • The mesoporous MnCo₂O₄ shows low overpotential, small Tafel slope, and robust durability. -- Abstract: The development of oxygen evolution reaction (OER) electrocatalysts with attractive price, robust activity, and superior durability are desirable for efficient water splitting. In the present work, a facile and fast colloid assisted ethylene glycol (EG) combustion synthesis strategy was developed to prepare mesoporous manganese cobaltate (MnCo₂O₄) with a large specific surface area (SSA). The as-prepared MnCo₂O₄ delivered a high SSA of 124.4 m² g⁻¹ with hierarchical mesopores in the range of 3–30 nm. It offered short diffusion paths and rich active sites, which can promote the OER catalytic activity. When applied as the electrocatalyst for OER, the mesoporous MnCo₂O₄ demonstrated an ultra-low overpotential of 0.24 V at 10 mA cm⁻², and a moderate Tafel slope with robust durability. This work not only puts forward a novel synthetic route towards mesoporous MnCo₂O₄ with high SSA but also reveals its tremendous prospects in the field of electrocatalytic water oxidation.