Emerging Pd-based electrocatalysts and supports for ethanol oxidation reaction: High-entropy and single-atom materials

Alkaline direct ethanol fuel cells (ADEFCs) offer a promising solution to reduce reliance on fossil fuels. Despite their advantages over hydrogen and methanol fuel cells, the anodic ethanol oxidation reaction (EOR) in ADEFCs faces challenges such as sluggish kinetics and high overpotentials, leading to reduced efficiency. To address these issues, highly active electrocatalysts are essential. This review highlights recent advancements in Pd-based high-entropy materials (HEMs) and single-atom catalysts (SACs) for EOR. Additionally, MXenes, a novel family of two-dimensional materials, have shown promise as supports for these electrocatalysts. We discuss the fundamental principles of EOR, the unique properties of these emerging materials, and their applications in EOR electrocatalysis. Finally, we provide an outlook on future research directions to enhance the commercialization of Pd-based electrocatalysts for ADEFC technologies.