Sustainable Dual-Template Fabrication of Hierarchical Pore Structure for Enhanced and Stable CO<sub>2</sub> Capture
Hao Li, Jiabin Niu, Kay Jin Tay, Mei Chee Tan, Hong Yee Low
Abstract
Micropores significantly impact the adsorption properties of porous materials, but their effective utilization often encounters diffusion limitations. Introducing hierarchical pore structures offers a promising solution. However, the sustainable fabrication of hierarchical structures remains challenging. Additionally, previous fabrication methods typically involve the use of nitrogen-containing compounds, complicating the exploration of the relationship between pore structure and CO 2 capture properties due to CO 2 ’s strong affinity for N-containing groups. Here, we report a dual-template approach to sustainably fabricate hierarchically porous carbon (HPC) and systematically investigate the effect of pore hierarchy on CO 2 capture. The resulting interconnected multiscale porous adsorbent exhibits superior CO 2 capture properties than that of other nitrogen-free porous adsorbents. The pore structure with high hierarchy, encompassing extra-large, macro-, meso-, and microscale features, shows a 27% enhancement in CO 2 capture capacity compared to that without extra-large and mesopores. Moreover, this HPC retains its uptake capacity and kinetics after 20 adsorption–desorption cycles, showcasing robust stability. This study provides a sustainable strategy for optimizing micropore sites, offering valuable insights for the design of advanced porous materials tailored for adsorption-related applications.