Bottom-up MOF-intermediated synthesis of 3D hierarchical flower-like cobalt-based homobimetallic phophide composed of ultrathin nanosheets for highly efficient oxygen evolution reaction

Abstract

In demand of implementing the replacement of fossil fuels, efficient oxygen evolution reaction (OER) catalysts are required in producing clean and low-cost hydrogen fuels via water splitting, the urgency and great necessity of which make it one of the greatest challenges for scientists and engineers concerned with research on energy issues. A novel bottom-up one-pot solvothermal strategy followed by low-temperature phosphorization was developed to prepare 3D hierarchical flower-like materials composed of ultrathin cobalt based bimetallic phosphide nanosheets (CoM-P-3DHFLMs) as cost-effective OER electrocatalysts, which are highly efficient and durable. Due to their unique structural and compositional advantages, the CoM-P-3DHFLMs not only achieve satisfying electrocatalytic efficiencies (η@10 mA cm−2 = 292 mV, 318 mV, and 307 mV for CoNi-, CoMn-, and CoCu-P-3DHFLM, respectively) comparable to IrO2 and RuO2 counterparts, but also exhibit long-term stability with subtle decrement after 10 h. The advantages of high efficiency, good stability, and free of noble metal make the as-prepared 3DHFLMs promising candidates for OER.