A series of ionic liquids (P_4,4,4,6BF₄, APMIMBF₄, P_4,4,4,6Triz, as well as the newly prepared anion dual-functionalized amino-triz IL P_4,4,4,6ATriz, etc.) supported on glass powder and SAPO-11 were prepared, and their interaction with CO₂ was investigated by “limited” temperature-programmed desorption. The results showed that the strength of the interaction of CO₂ with IL/glass powder (11 wt%) followed the order P_4,4,4,6BF₄ < APMIMBF₄ < P_4,4,4,6Triz < P_4,4,4,6ATriz. Two desorption peaks were observed for P_4,4,4,6Triz, probably attributed to the two sites of interaction between Triz and CO₂, and the Gaussian 03 program was employed to obtain the optimized structures, revealing the interaction between P_4,4,4,6Triz and CO₂. When ILs were confined in the nanopores of SAPO-11, the desorption capacity and interaction strength increased because of the nano-confinement effect. Meanwhile, the loading, as well as the structure of ILs and Na₂CO₃-modified SAPO-11, significantly affected the interaction between CO₂ and ILs. Besides, P_4,4,4,6ATriz/SAPO-11 (modified with Na₂CO₃, 30 wt%) with a maximum CO₂ desorption capacity of 1.55 mole_CO2/mole_ILs could reversibly adsorb CO₂ 15 times without any apparent reduction in the desorption capacity.