Electrodeposition and Electrochemical Characterization of Nickel-BasedNanocomposite Coatings Incorporating MIL-88B(Fe) MOF Particles forEnhanced OER Catalysis

This study explores the synthesis, electrodeposition, and electrochemical performance of nickel-based nanocomposite coatings embedded with MIL-88B(Fe) metal-organic framework (MOF) particles, designed to enhance catalytic efficiency for the oxygen evolution reaction (OER) in alkaline solutions. MIL-88B(Fe) was synthesized using a solvothermal approach, with its structure characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and field emission scanning electron microscopy (FESEM). The Ni-MOF composites were electrodeposited in both a conventional Watts bath and a diluted nickel sulfate bath, and their overpotentials and Tafel slopes were analyzed to assess their catalytic performance. Results from linear sweep voltammetry (LSV) and Tafel slope measurements indicate that coatings from the Watts bath reduce the overpotential from 724 mV to 543 mV and a Tafel slope decrease from 210 mV·dec ¹ to 80 mV·dec ¹, signifying improved reaction kinetics and electron transfer rates. Coatings from the diluted bath further enhance the reaction kinetics, with an overpotential drop from 766 mV to 550 mV and a Tafel slope decrease from 246 mV·dec ¹ to 87 mV·dec ¹. These findings underscore the synergistic effect between MIL-88B(Fe) particles and the nickel matrix, demonstrating that even partially degraded MOF structures can substantially contribute to the OER catalysis. The study highlights the potential of optimized bath compositions for producing durable and efficient catalytic coatings for electrochemical applications.

Electrodeposition and Electrochemical Characterization of Nickel-BasedNanocomposite Coatings Incorporating MIL-88B(Fe) MOF Particles forEnhanced OER Catalysis Keywords:

Nickel-based nanocomposite coatings , Metal-organic frameworks (MOFs) , Oxygen evolutionreaction (OER) , Electrodeposition , Tafel slope , overpotential