Bimetallic metal–organic framework-derived carbon nanocubes as efficient electrocatalysts for oxygen evolution reaction

Abstract

The design and synthesis of efficient electrocatalysts are important for electrochemical conversion technologies. The oxygen evolution reaction (OER) is a key process in such conversions, having applications in water splitting and metal–air batteries. Here, bimetallic carbon nanocubes electrocatalysts are derived from Hofmann-type metal–organic frameworks by carbonization and oxidization (FeNi@OCNC). FeNi@OCNC achieved a current density of 10 ​mA ​cm−2 at a low overpotential of 300.4 ​mV with a very small Tafel slope of 55.4 ​mV dec−1 in 1 ​M KOH, and its activity shows 12 ​h stability. We propose that the coupling effect between Fe, Ni metals is crucial for tuning the electrocatalytic activity, which makes FeNi@OCNC have more oxygen vacancies and higher carbon graphitization degree, thus showing excellent activity. The result may illustrate that bimetallic metal–organic framework-derived carbon nanocubes can be prospective materials for oxygen evolution reaction.