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

ChemSusChem. 2019 Jun 7;12(11):2480-2486. doi: 10.1002/cssc.201900194. Epub 2019 Apr 29.

Abstract

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 (H3 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.

Keywords: electrocatalysis; gels; metal oxides; oxygen evolution reaction; water oxidation.