Sunlight-Controlled CO2 Separation Resulting from a Biomass-based CO2 Absorber

Abstract Renewable solid sorbents for CO2 capture and storage have shown great potentials for the sake of gaseous separation, tail gas treatment, environmental regulation and climate governance. However, current existed preparation and reusability of solid sorbents are generally subject to high energy consumption and complicated procedure. Herein, a light-controlled CO2 separation system with high working temperature resulting from natural sawdust combined with polyethyleneimine is fabricated, which involves low energy input and few operating sequences. This system shows a direct and ratiometric response to sunlight illumination by which CO2 can be reversibly adsorbed and released. This light-controlled CO2 separation process is prospective to become an attractive alternative to traditional alkaline CO2 collection method in terms of its convenience and low cost. As a practical demonstration, CO2 mixed with N2 is successfully separated through this light-controlled carbon capture and storage (CCS) system, which offers great promise for CO2 capture and enrichment with applicability across a wide range of scales.