A Review on Recent Progress in the Aspect of Stability of Oxygen Reduction Electrocatalysts for Proton-Exchange Membrane Fuel Cell: Quantum Mechanics and Experimental Approaches

Proton-exchange membrane fuel cells (PEMFCs) have been intensively developed. Their advantages include low working temperature, high power density, and fast reaction rate. PEMFCs are considered the most promising candidates for the reliable and efficient large-scale conversion system of hydrogen in automotive engines, distributed power generation, and portable electronic applications. In time, the current use of significant amounts of precious metals as catalysts, especially for the oxygen reduction reaction (ORR) at the cathode, can limit the sustainable utilization of PEMFCs. The significant findings in studies, which combine experiments with theories, markedly improved the understanding of catalytic activity based on the interpretation of electronic configuration. For the commercialization of PEMFCs, ensuring the reliable durability of the system is an important prerequisite. However, voluminous studies on the durability of crucial materials are still insufficient. In particular, studies on improving the durability using quantum mechanics are comparatively rare relative to the studies on the nature of the activity. Therefore, the aim of this Review is to summarize the recent trends in the research on catalysts in terms of durability by combining quantum mechanics simulations with experiments to provide some insights and potential directions for the future design of stable ORR catalysts for PEMFCs.