Advanced carbon supports for elevated-temperature PEMFCs: Multiscale thermal transport, graphitization strategies, and interfacial engineering

Proton exchange membrane fuel cells (PEMFCs) are a widely adopted clean energy technology. However, performance degradation under dynamic operation and at elevated temperatures remains a major challenge. One key contributor to this degradation is heat accumulation stemming from insufficient thermal conductivity. The catalyst layer is the primary heat source of the PEMFCs. The thermal conductivity of the carbon support, which serves as the structural backbone of the catalyst layer, governs the upper limit of heat dissipation within the catalyst layer. This review comprehensively analyzes thermal conduction mechanisms in carbon materials, considering both bulk-phase and interfacial perspectives, and identifies critical influencing factors. The review also summarizes the thermal conductivity characteristics of various carbon materials and methodologies aimed at improving bulk and interfacial thermal conduction. Principal thermal measurement techniques are also critically examined. Collectively, these analyses provide foundational insights for developing advanced, high-thermal-conductivity carbon supports in PEMFCs.