Recent Development in Boride‐Based Electrodes and Their Water‐Splitting Potential by Electrocatalysts

ABSTRACT

Electrochemical water splitting is considered a key pathway toward green hydrogen production; however, large‐scale implementation requires cost‐effective and durable electrocatalysts based on earth‐abundant elements rather than noble metals. In this context, transition‐metal and rare‐earth borides have attracted attention as electrode materials due to their high electrical conductivity, strong metal–boron interactions, and tunable electronic structures that influence HER and OER kinetics. This review is a critical overview of the modern trends in electrodes based on borides and is narrowed down to synthesis routes, phase/defect engineering, nanostructuring, and multi‐metallic design to regulate the exposure of active sites, charge transfer kinetics, and intermediate adsorption energetics. Such methods as the optimization of the activity and stability, such as heterostructure formation, carbon/oxides/phosphides, and surface reconstruction control are taken into consideration based on the practical performance (over potential, Tafel slope, and stability) and also scalability effects. The other issues include scalable synthesis, time stability in anodic operation of OER, and corrosion in acidic conditions of interest to proton exchange membrane (PEM) electrolyzes. Lastly, we also mention the possibilities of rational catalyst design by the use of density functional theory (DFT)‐informed screening, operando/in situ spectroscopy to determine the active phases actually occurring, and correlation between mechanism structure–performance relationships. Recent advances in scalable synthesis strategies and operando characterization have improved understanding of active phase evolution and enhanced the rational design of boride‐based electrocatalysts for durable water electrolysis.