CuCl₂-Activated Sustainable Microporous Carbons with Tailorable Multiscale Pores for Effective CO₂ Capture

Porosity is the key factor in determining the CO2 capture capacity for porous carbon-based adsorbents, especially narrow micropores of less than 1.0 nm. Unfortunately, this desired feature is still a great challenge to tailor micropores by an effective, low-corrosion, and environmentally friendly activating agent. Herein, we reported a suitable dynamic porogen of CuCl2 to engineer microporous carbons rich in narrow micropores of <1.0 nm for solving the above problem. The porosity can be easily tuned by varying the concentration of the CuCl2 porogen. The resultant porous carbons exhibited a multiscale micropore size, high micropore volume, and suitable surface nitrogen doping content, especially high-proportioned ultromicropores of <0.7 nm. As adsorbents for capturing CO2, the obtained microporous carbons possess satisfactory CO2 uptake, moderate heat of CO2 adsorption, reasonable CO2/N-2 selectivity, and easy regeneration. Our work proposes an alternative way to design porous carbon-based adsorbents for efficiently capturing CO2 from the postcombustion flue gases. More importantly, this work opens up an almost-zero cost and industrially friendly route to convert biowaste into high-added-value adsorbents for CO2 capture in an industrial practical application.