Ru doped bimetallic phosphide derived from 2D metal organic framework as active and robust electrocatalyst for water splitting

The exploration of earth-abundant, highly active, and stable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a vital but challenging step for sustainable energy conversion processes. Herein, a super-low ruthenium (Ru) (0.6 wt%) doped bimetallic phosphide derived from 2D MIL-53(NiFe) MOF nanosheets (i.e., Ru-NiFeP/NF) on nickel foam was developed via a continuous two-step hydrothermal followed by phosphorization process. The as-obtained Ru-doped NiFeP/NF with optimized electronic structure and enhanced electric conductivity delivers admirable performance for HER in a wide pH range, which requires overpotentials of 29, 105, and 56 mV to reach current density of 10 mA·cm−2 in acid, neutral, and alkaline media, respectively. For the OER, only requires an overpotential of 179 mV to achieve 10 mA·cm−2 in alkaline media. In a two-electrode alkaline electrolyzer, the as-prepared Ru-NiFeP/NF electrodes only need 1.47 V to yield 10 mA·cm−2, which is superior to the integrated RuO2 and Pt/C couple electrode (1.5 V). This work highlights the rational design of MOF-derivates and electronic structure engineering strategy by heteroatom doping, which can be extended to design and prepare other high-performance MOF-based electrocatalysts.