Mesoporous Ultrathin Cobalt Oxides Nanosheets Grown on Carbon Cloth as a High-Performance Electrode for Oxygen Evolution Reaction

Developing high-performance and low-cost electrode for oxygen evolution reaction (OER) is a crucial step to produce clean and sustainable energy sources. Herein, we report mesoporous ultrathin cobalt oxides nanosheets (∼7 nm) grown on carbon cloth (denoted as CoOx/CC) as an efficient electrode for water oxidation. The electrode was fabricated via a simple calcination of cobalt alkoxyacetate grown on carbon cloth under air atmosphere. The as-synthesized CoOx/CC electrode exhibited better electrocatalytic performance for OER in 1.0 M KOH, with lower overpotential of ∼263 mV at 10 mA cm–2, lower Tafel slope of 56.07 mV dec–1, and better stability, in comparison with commercial IrO2 and Co3O4 nanoparticles. Also, the OER performance of CoOx/CC-10 is among the best of the reported cobalt oxides electrocatalysts. Detailed characterizations reveal that the interaction between cobalt oxides and CC, unique 3D structures, ultrathin nature of nanosheets, high specific surface area, nanoporous structures, and fast electron transfer rate contributed to the enhanced catalytic activity. More importantly, the synthetic strategy applied here has great potential application in large-scale production of efficient electrodes in water splitting technology.