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arXiv · 2410.16715

Directing the Electrode-Electrolyte Interface Towards Active Nickel-Based Electrocatalysts for Oxygen Evolution Reaction

Abstract

A comprehensive understanding of the electrode-electrolyte interface in energy conversion systems remains challenging due to the complex and multifaceted nature of interfacial processes. This complexity hinders the development of more efficient electrocatalysts. In this work, we propose a hybrid approach to the theoretical description of the OER process on nickel-iron-based oxyhydroxides ($\gamma$-Ni$_{1-x}$Fe$_x$OOH) electrodes in alkaline media as a model system. Multiple reaction pathways represented by the single- and dual-site mechanisms were investigated by taking into account the realistic structure of the catalyst, the doping, and the solvation effects using a simple and computationally feasible strategy. Accounting for the variable solvation effects considerably affects the predicted overpotential in a roughly linear relationship between overpotential and dielectric constant. By incorporating quantum chemical simulations with kinetic modeling, we demonstrate that tuning the local solvation environment can significantly enhance the OER activity, opening new routine ways for elucidation of the emerging issues of OER processes on transition metal oxide surfaces and design of cost-effective, efficient electrocatalytic systems.

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Ben Wang, Tomohiro Fukushima, Hiro Minamimoto, Andrey Lyalin, Kei Murakoshi, Tetsuya Taketsugu. 2024-10-22. Directing the Electrode-Electrolyte Interface Towards Active Nickel-Based Electrocatalysts for Oxygen Evolution Reaction. https://arxiv.org/abs/2410.16715

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