Highly dispersed Ir-Co nanoparticles in leaf-like carbon support derived from zeolitic imidazolate framework for liquid fuel production via Fischer-Tropsch synthesis

Fischer–Tropsch synthesis (FTS) is an essential process for producing sustainable clean fuels and high-value chemicals, offering a promising pathway for efficient chemical energy conversion. Despite decades of intensive research, the development of FTS catalysts with improved activity and selectivity remains in high demand. Herein, we propose a catalytic system that transforms a conventional Co-based zeolitic imidazolate framework (Co ZIF) into a bimetallic Ir-Co supported on a leaf-like Co 2D ZIF structure, significantly enhancing metal exposure and improving catalytic performance. The Co 2D ZIF structure enables higher dispersion of metal particles and improved mass transfer characteristics (e.g., mesoporosity). These structural advancements result in higher CO conversion and effectively suppress undesired side reactions, such as CH 4 formation. The incorporation of Ir in bimetallic Ir-Co 2D ZIF catalysts increases the Co particle size to an optimal range for CO activation, promotes the formation of the hexagonal close-packed Co 0 phase, and modifies the electronic states of the metal species. These combined effects contribute to a remarkable improvement in the catalytic activity and selectivity for FTS. As the Ir content increases, both the CO turnover frequency and C 5+ hydrocarbon selectivity are significantly enhanced. Moreover, compared with conventional Co catalysts supported on carbon-based materials, the Ir-Co 2D ZIF catalysts exhibit a superior catalytic performance under identical reaction conditions. This study demonstrates a catalytic design strategy that can significantly advance the development of high-performance energy conversion catalysts by changing the catalyst structure and inducing bimetallic effects. A Ir-Co catalyst having a 2D ZIF structure exhibits enhanced CO conversion and liquid fuel selectivity in Fischer-Tropsch synthesis due to improved metal dispersion, mass transport, and electronic interaction between Co and Ir. • Mesoporous leaf-like Co 2D ZIF provided better metal dispersion and mass transfer • Ir promoted hcp Co formation and bimetallic effect, enhancing CO turnover frequency • Ir-Co 2D ZIF improved Co conversion and C 5+ selectivity with lower CH 4 selectivity • Structural and electronic synergy in Ir-Co 2D ZIF enhanced liquid fuel production