Microstructural Tailoring of Metal-embedded Carbon Fiber for Scalable and Robust Catalyst Design

Abstract

Metal-embedded carbon fiber catalysts, which integrate catalytically active metal species within carbon fiber architecture through precise microstructural control, have emerged as promising candidates for various energy conversion and organic synthesis applications. Despite the considerable advantages of carbon fiber as a catalyst support, including electrical conductivity, mechanical robustness, and scalable manufacturing capability, the development of metal-embedded carbon fiber catalysts has been hindered by challenges in controlling metal- carbon interfaces and achieving uniform metal distribution during the fiber formation process. In this regard, this dissertation aims to present systematic approaches for designing scalable and robust metal-embedded carbon fiber catalysts through microstructural tailoring, with particular focus on the metal-polymer interactions during the precursor stage and their evolution through the carbonization process. The development of metal-embedded carbon fiber self-supported catalysts, which eliminate the need for additional binders or supports while maintaining structural integrity, is demonstrated through two distinct strategies: uniformly distributed embedding and surface-selective embedding. The processing-structure-property relationships in ruthenium-embedded carbon fiber electrocatalysts are investigated in Chapter 2, presenting both uniformly distributed (EFEC) and surface-selective (SFEC) embedding approaches for hydrogen evolution reaction. The correlation between carbonization conditions and catalytic performance is systematically explored, demonstrating remarkable stability and activity through optimized microstructural development. The effect of tension control on metal exsolution and carbon crystallinity during the carbonization process is also determined, providing crucial insights for scalable manufacturing. In Chapter 3, the application scope is extended to palladium-embedded carbon fiber catalysts for selective hydrogenation reactions, where controlled low-temperature carbonization enables precise metal evolution while maintaining strong metal-support interactions. This approach addresses critical challenges in precious metal catalyst recovery while achieving superior selectivity in organic transformations. Finally, Chapter 4 summarizes the key findings and presents future perspectives for metal- embedded carbon fiber catalyst development. Through systematic investigation of precursor design, process optimization, and structure-property relationships, this work establishes a new paradigm for scalable catalyst manufacturing that effectively bridges laboratory innovation with industrial application.