Recent Development of Oxygen Evolution Electrocatalysts in Acidic Environment.

Proton exchange membrane (PEM) water electrolysis is a leading method for hydrogen production. Oxygen evolution reaction (OER) at the anode is a key determinant of system efficiency. Despite its importance, OER electrocatalysts in acidic environments face significant challenges. Most catalysts degrade under acidic and oxidative conditions. This instability complicates mechanistic studies and hinders progress. Prior research has shown that noble metals like iridium and ruthenium are active but costly and unstable. Non-noble metal alternatives remain underdeveloped. This gap motivated a need to better understand OER mechanisms and catalyst stability. No prior work had resolved the interplay between structure and activity in acidic OER. This review addresses those unresolved questions.

This review aims to clarify recent advances in OER electrocatalysts for acidic environments. The study focuses on understanding the mechanisms of OER in proton exchange membrane (PEM) systems. It seeks to analyze strategies for improving both activity and stability of catalysts. The authors also aim to summarize the state-of-the-art materials for acidic OER. By reviewing prevailing mechanisms, the paper hopes to guide future catalyst design. It addresses the challenge of catalyst instability under acidic and oxidative conditions. The study also explores the role of surface reconstruction in catalyst degradation. This work provides a foundation for developing more efficient and durable OER electrocatalysts.

The authors conducted a comprehensive literature review of oxygen evolution reaction (OER) electrocatalysts in acidic environments. They analyzed the prevailing mechanisms of OER and their structure-activity relationships. The study examined macro- and micro-level strategies to enhance OER activity. The authors summarized key factors influencing catalyst stability in acidic conditions. They reviewed the performance of noble-metal-based catalysts like iridium and ruthenium. Non-noble-metal alternatives were also evaluated for activity and stability. Surface reconstruction as a degradation pathway was discussed in detail. The review synthesizes findings from experimental and theoretical studies to provide a holistic view.

The review identifies structure-activity relationships as central to OER catalyst design in acidic environments. Noble-metal catalysts like iridium and ruthenium show high activity but suffer from poor stability. Non-noble-metal catalysts, including transition metal oxides and phosphides, are emerging as promising alternatives. Surface reconstruction is a key factor in catalyst degradation under acidic and oxidative conditions. The authors report that microstructural engineering improves OER activity by enhancing active site exposure. Strategies such as alloying and surface modification are effective in stabilizing catalysts. The study highlights the importance of understanding OER mechanisms at the atomic level. These findings suggest that further research into surface reconstruction and structure-activity relationships will guide future catalyst development.

The authors conclude that understanding OER mechanisms is essential for designing efficient catalysts in acidic environments. They propose that structure-activity relationships should guide future catalyst development. Surface reconstruction is identified as a critical challenge for catalyst stability. The review suggests that non-noble-metal catalysts offer a viable alternative to costly noble metals. The authors emphasize the need for more research into microstructural and surface-level modifications. They propose that combining experimental and theoretical approaches will accelerate progress. The study suggests that addressing instability is key to improving PEM water electrolysis efficiency. These conclusions align with the authors' goal of guiding future catalyst design and stability improvement.