Facile synthesis of an amine hybrid aerogel with high adsorption efficiency and regenerability for air capture via a solvothermal-assisted sol-gel process and supercritical drying

An amine hybrid resorcinol-formaldehyde/silica composite aerogel (AH-RFSA) was developed for the first time through a solvothermal-assisted sol-gel process combined with supercritical drying (SCD). The CO₂ adsorption performances of AH-RFSA in air were investigated. The results reveal that the solvothermal temperature negatively affects the CO₂ adsorption capacity of AH-RFSA. Water favors the CO₂ adsorption capacities, especially the useful CO₂ adsorption capacity. The total CO₂ adsorption capacity achieved with the new adsorbent at 25°C in dry and humid air is 1.80 and 2.57 mmol g^-1, respectively. The useful CO₂ adsorption capacity of AH-RFSA in humid air is as high as 1.85 mmol g^-1. The adsorbent preparation method is inspiring and the resulting adsorbent is exceptional in capacity and regenerability.