Highly efficient overall water splitting enabled by a bimetallic FeRu-MOF electrocatalyst

Abstract

The ongoing depletion of fossil fuels and the resulting environmental degradation underscore a pressing demand for alternative energy sources. High-efficiency electrocatalytic materials are examined for their potential to enable water splitting in clean hydrogen production. A bimetallic electrocatalyst (FeRu-BDC/NF) was prepared via hydrothermal synthesis. The material's structure and composition were examined via various characterization methods, with subsequent electrochemical testing within the alkaline electrolyte. Systematic experiments revealed that the incorporation of Ru can optimize the electronic structure and conductivity of monometallic Fe-BDC. As a result, at 10 mA cm⁻², the overpotential in the hydrogen evolution reaction (HER) process on FeRu-BDC/NF was a mere 54 mV; at 50 mA cm⁻², the overpotential in the oxygen evolution reaction (OER) process was 230 mV. In the comprehensive water splitting measurement, the FeRu-BDC/NF||FeRu-BDC/NF catalyst demonstrated exceptional electrochemical stability and catalytic performance, delivering 10 mA cm⁻² current density with a cell voltage of just 1.47 V. Additionally, DFT calculations indicated that incorporating Ru into MOFs had the capacity to fine-tune the electronic configuration of the metal center. This, in turn, led to an optimized binding affinity between H₂O and H*, ultimately elevating the efficacy of electrochemical water splitting. The methodology put forth in this research offers a fresh and innovative strategy for the creation of materials that are not only efficient and stable but also economically viable.