Metal-organic framework-derived self-supporting metal boride for efficient electrocatalytic oxygen evolution reaction

Metal boride has been verified as the highly efficient catalyst for oxygen evolution reaction. However, the design and synthesis of self-supporting metal borides remain a big challenge. Herein, metal-organic framework-derived metal boride electrode is in-situ formed on 3D framework via controllable boronation strategy, which is of great significance to the construction of self-supporting metal borides. This strategy not only produces the metal boride materials but also achieves the metal borides based self-supporting electrode with multiple structures. The as-fabricated CoFe-PBA-B exhibits a low overpotential of 255 mV at the current density of 10 mA cm-2 and a low Tafel slope of 51 mV dec-1 due to the enhanced active sites of multiple structures and effective electronic interaction between metal atoms and boron atom. In addition, CoFe-PBA-B shows good stability with negligible weaken in current density for 40 h. This work provides new boulevard for the design and synthesis of self-supporting metal borides for electrochemical OER.