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Traditional passive jamming media always suffer from high density and impedance mismatch, which have restricted them from being directly utilized as microwave absorbing materials. Herein, carbonized Kevlar nanofiber/carbon nanotube/ magnetic nanoparticle (CKNF/CNT/MNP) hybrid aerogel fibers with low apparent density (0.12 g/cm 3 ) and adjustable electromagnetic parameters are fabricated for microwave absorption. The minimum reflection loss (RL min ) of the aerogel fibers reaches −59 dB at 14.8 GHz, and the effective absorption bandwidth (EAB) reaches the whole Ku-band with 1.8 mm thickness. In addition, the aerogel fibers can be further developed into microwave absorptive smoke, which exhibits a wide microwave absorption frequency (5.5−15.5 GHz).

The pursuit of efficient CO2 capture materials remains an unmet challenge. Especially, meeting both high sorption capacity and fast uptake kinetics is an ongoing effort in the development of CO2 sorbents. Here, a strategy to exploit liquid‐in‐aerogel porous composites (LIAPCs) that allow for highly effective CO2 capture and selective CO2/N2 separation, is reported. Interestingly, the functional liquid tetraethylenepentamine (TEPA) is partially filled into the air pockets of SiO2 aerogel with left permanent porosity. Notably, the confined liquid thickness is 10.9–19.5 nm, which can be vividly probed by the atomic force microscope and rationalized by tailoring the liquid composition and amount. LIAPCs achieve high affinity between the functional liquid and solid porous counterpart, good structure integrity, and robust thermal stability. LIAPCs exhibit superb CO2 uptake capacity (5.44 mmol g−1, 75 °C, and 15 vol% CO2), fast sorption kinetics, and high amine efficiency. Furthermore, LIAPCs ensure long‐term adsorption–desorption cycle stability and offer exceptional CO2/N2 selectivity both in dry and humid conditions, with a separation factor up to 1182.68 at a humidity of 1%. This approach offers the prospect of efficient CO2 capture and gas separation, shedding light on new possibilities to make the next‐generation sorption materials for CO2 utilization.