Metal–Organic Gel-Derived Multimetal Oxides as Effective Electrocatalysts for the Oxygen Evolution Reaction

Graphical Who let the MOGs out? This work reports a compositionally alterable metal–organic gel (MOG) to obtain spinel-type metal oxide (MO) with excellent electrocatalytic oxygen evolution reaction (OER) activity. The capacity for catalytic water oxidation could be improved by adjusting the metal composition and ratio in the MOG. This investigation provides a facile approach to obtain multimetal oxides with high electrocatalytic performance. Exploring efficient and durable catalysts derived from earth-abundant and cost-effective materials is a highly desirable route to overcome the sluggish anodic oxygen evolution reaction (OER). A series of multinary metal–organic gels (MOGs) with various and alterable metal element compositions are prepared by straightforward mixing of metal ions with ligand 4,4′,4′′-[(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)]tribenzoic acid (H 3 TATAB) in solution at room temperature. Spinel-type metal oxides with excellent electrocatalytic OER performance were then obtained through calcination of the as-synthesized MOGs. In electrochemical testing, the trimetallic oxide CoFeNi-O-1 (derived from the MOG with a Co/Fe/Ni molar ratio of 5:1:4) exhibits remarkable catalytic activity with a low overpotential of 244 mV at a current density of 10 mA cm −2 and a small Tafel slope of 55.4 mV dec −1 in alkaline electrolyte, outperforming most recently reported electrocatalysts. This work not only provides a promising OER catalyst and enriches the application of MOGs in the catalytic field, but also offers a facile new route to acquiring multicomponent metal oxides with high electrocatalytic activity.