Fe2W18Fe4@MOF-Ni-100 Nanocomposite: Insights into Synthesis and Application As a Promising Material Towards the Electrocatalytic Water Oxidation

In this research, a new nanocomposite was synthesized via the sol-gel method by encapsulation of tetranuclear sandwich -type hetropolyanion (Na9K[(FeW9O34)2Fe4(H2O)2].32H2O , abbreviated as Fe2W18Fe4 , on the surface of MOF-Ni-100 for the first time. The as-prepared nanocomposite (Fe2W18Fe4@MOF-Ni-100) was examined using different microscopy and spectroscopy techniques, including FT-IR, UV-vis, XRD, SEM, EDX, and BET techniques. The assembled Fe2W18Fe4@MOF-Ni-100 nanocomposite served as a potential heterogeneous catalyst in the water oxidation process for the purpose of oxygen evolution reaction (OER) at neutral pH conditions (N2-saturated 0.1 M Na2SO4). The electrochemical characteristics of the Fe2W18Fe4@MOF-Ni-100 nanocomposite was assessed through cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) methods. The desired nanocatalyst displayed a low onset potential of 1.1 V vs. NHE and low overpotential of 269 mV at a current density (j) of 10 mA center dot cm-2 with a Tafel slope of 73 mV.dec-1(pH = 7). Furthermore, the Fe2W18Fe4@MOF-Ni-100 nanocomposite exhibited remarkable stability and retained its catalytic activity even after 200 catalytic cycles. (c) 2024 The Society of Powder Technology Japan. Published by Elsevier BV and The Society of Powder Technology Japan. All rights reserved.