Ni‐Co‐based bimetal organic framework as superior electrode material for hydrogen evolution reaction and supercapacitors

Abstract

Metal‐organic frameworks (MOFs) possess several desirable properties, including a homogeneous crystal structure, variable porosity, high surface area, and a notable adsorption affinity, making them highly promising contenders for deployment as electrode materials in supercapacitors (SCs) and water electrolyzers, which are acknowledged for the ever‐increasing demand for instantaneous energy. Herein, we report the rationally assembled Ni‐Co‐based bimetallic MOF compounds using a glutaric acid as an organic ligand and low‐temperature hydrothermal treatment that surmounts the electrocatalytic and electrochemical charge storage activity in an alkaline medium. The NiCo‐MOF surpassed the hydrogen evolution reaction (HER) among other as‐synthesized materials, exhibiting the least overpotential of 182 mV at 10 mA/cm2 of current density, showed splendid kinetics with a turnover frequency of 2.86 s−1, and higher stability after 1000 HER cycles in 1 M KOH. Furthermore, NiCo‐MOF impetuses were employed for SC application and displayed the highest specific capacitance of 978 F/g than Ni‐MOF (706 F/g) and Co‐MOF (91 F/g) at 1 A/g of current density. Theoretical studies exhibited that the optimal electronic coupling and synergistic effect due to Ni‐Co sites enhances the overall electronic properties of NiCo‐MOF. Therefore, enhancing its electrochemical performance concerning water‐splitting and charge storage. This study showcases a novel approach for producing ultrathin and flexible bimetallic MOF‐based electrode material to enrich the performance in electrocatalytic HER and SCs.