Revealing the effect of various organic ligands on the OER activity of MOF-derived 3D hierarchical cobalt oxide @ carbon nanostructures

Intensive research work on the robust and highly active non-precious electrocatalysts for oxygen evolution reactions (OERs) under lenient conditions has been attracted much attention to industrialize water-splitting processes. In this work, we design and develop the cost-effective and highly active Co₃O₄@C nanostructures derived from two different metal-organic framework (MOF) ligands, including terephthalic acid (PA) and trimesic acid (TMA), through a wet chemical strategy. The unique morphologies (donuts and nanorods over a carbon layer) and excellent surface area of the as-prepared catalysts including Co₃O₄@C-PA and Co₃O₄@C-TMA are resulted the increased active centers for OER activity. Among the prepared electrocatalysts, Co₃O₄@C-TMA exhibits favorable Tafel kinetics (85.18 mV dec⁻¹) and small overpotential (320 mV@10 mA cm⁻²) for oxygen evolution. In addition to design the effective Co₃O₄@C electrodes for OER activity, this study also proposes the various multi-functional catalysts for renewable energy conversion applications.