Bridging Mechanisms and Strategies: MXene-Based Electrocatalysts for the Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• The oxygen evolution reaction (OER) is crucial for water electrolysis but is kinetically limited.
• MXenes, 2D transition-metal compounds, offer advantageous properties for OER catalysts.
• Challenges include limited active sites, restacking, and oxidative instability of MXenes.

Purpose of the Study:

• To review fundamental OER pathways (AEM, LOM, OPM) for mechanistic understanding.
• To present a systematic framework for MXene catalyst modification across multiple scales.
• To guide the design of efficient, durable, and verifiable MXene-based OER electrodes.

Main Methods:

• Discussion of fundamental OER mechanisms.
• Construction of a multi-level modification framework (atom, interface, morphology, composite).
• Analysis of modification strategies with specific examples.

Main Results:

• Analysis of modification strategies including atomic-level regulation, interface, morphology, and composite engineering.
• Distinction between beneficial surface reconstruction and destructive oxidation.
• Identification of key challenges: active site ambiguity, material state diversity, and industrial stability.

Conclusions:

• MXene-based catalysts require tailored modification strategies to overcome limitations.
• Understanding structure-activity-stability relationships is key for rational design.
• Future research should focus on resolving active site ambiguity and ensuring industrial-scale stability.