Metal-organic frameworks-derived hollow-structured iron-cobalt bimetallic phosphide electrocatalysts for efficient oxygen evolution reaction

Abstract

The oxygen evolution reaction (OER) is a cornerstone reaction for many renewable energy technologies. Developing low-cost and durable alternatives to precious-metal catalysts with high activity for OER are highly desirable to reduce the processing cost and complexity of renewable energy systems. Recently, metal phosphides based on earth-abundant transition metals, especially bimetallic phosphates have emerged as promising candidates for efficient OER catalysts. The rational design of nanostructured bimetallic phosphates is critical for the practical applications of these electrocatalysts, which requires a well understanding of the composition control and nanocrystal growth process. Herein, we report a facile strategy for the synthesis of novel iron-cobalt bimetallic phosphides (FeCoP) with hollow structures by phosphating Fe (Co)-centered metal-organic frameworks (MOFs). The resultant FeCoP hollow polyhedron, which have large specific surface area providing rich catalytic active sites, show excellent electrocatalytic activity towards OER with low overpotential, small Tafel slope, and remarkable stability. This work provides a new strategy for exploring efficient phosphide catalysts and opens up new avenues for the development of OER catalysts.