Rational design of β-cyclodextrins-derived hierarchically porous carbons for CO2 capture: The roles of surface chemistry and porosity on CO2 capture

Abstract

CO2 capture, storage and utilization (CCSU) is the most promising strategy for ameliorating the ever-increasing atmospheric CO2 concentrations problem. The development of advanced porous solid adsorbents for efficient CCSU is a burgeoning interest in materials science. Currently, porous carbon-based adsorbents face the major challenge of balancing the structural features of porosity and surface chemistry for CCSU in a durable and scalable material. To this end, we designed hierarchically porous carbons with tailorable porosity and adjustable surface chemistry, and clarify the influence of porosity and surface chemistry on CO2 capture. Meanwhile, the systematic study revealed the synergetic effect of microporosity of less than 10 Å and surface chemistry on CO2 capture, and the synergistic effect mechanism of various surface groups on CO2 capture property was also ascertained in detail. Porosity was found to be the determinant role on CO2 capture, in particular the microporosity of < 10 Å and ultramicroporosity of < 7.0 Å. While, surface chemistry played a significant role on the improvement of CO2 capture, especially the CO2/N2 selectivity at higher temperature. Importantly, this work provided an instructive guideline for rational design of high-efficient porous carbon CO2 adsorbents with a balanced porosity and surface chemistry property.