Fluorinated metal-organic framework aerogels with enhanced moisture resistance and efficient gas diffusion for CO2 capture

•UiO-66-NH2-F4 were assembled on the ANFs to develop hierarchical porous structure.•UiO-66-NH2-F4 aerogels showed a CO2 adsorption capacity of 4.88 mmol/g (70 % RH).•UiO-66-NH2-F4 aerogels had a high CO2/N2 adsorption selectivity of 29.•The adsorption capacity could remain up to 96.96 % after fifty times of usage. Escalating CO2 levels in confined spaces threatens human well-being and safety, underscoring the urgent need for effective CO2 mitigation strategies. Metal-organic frameworks (MOFs), with their large surface areas and capacious pores, represent a promising avenue for CO2 capture. However, their application is often limited by susceptibility to moisture and lack of uniformity in mesopore distribution. Here, we present a novel approach involving ligand fluorination modification and pore reconstruction to fabricate ultralight, highly moisture resistant, and hierarchically porous UiO-66-NH2-F4 aerogels. This design ingenuity promotes the formation of an efficient gas transport network and generates an abundance of micropores decorated with hydrophobic units, effectively shielding CO2 adsorption from the interference of water molecules. The UiO-66-NH2-F4 aerogels exhibit an impressive CO2 adsorption capacity of 5.18 mmol/g (dry) and 4.48 mmol/g (70 % RH) at 298 K, a remarkable CO2/N2 selectivity of 29, and exceptional cyclability. Density functional theory (DFT) calculations further elucidate the robust binding interactions of these CO2-selective UiO-66-NH2-F4 aerogels, attributing them to the tailed pore environment created by fluorinated hydrophobic groups and the accessibility of adsorption sites. This work charts a promising course for developing moisture-resistant and hierarchically porous MOF aerogels, which are poised to revolutionize CO2 adsorption practices in confined environments.