Amines in porous materials have been employed as active species for the selective CO

2

adsorption from natural gas because of their target-specific interactions. Nevertheless

it is difficult to modulate such strong interactions to reach a high efficiency in the adsorption processes. Herein

we fabricated light-responsive adsorbents with tunable adsorbent-adsorbate interactions for CO

2

capture. The adsorbents were synthesized by introducing primary and secondary amines into a mesoporous silica that had been grafted with azobenzene groups on the surfaces. The target-specific amine sites render the adsorbents significantly selective in the uptake of CO

2

over CH

4

and the azobenzene groups were used as light-responsive switches to influence the adsorbent-adsorbate interactions. The adsorbents can freely adsorb CO

2

when the azobenzene groups are in the

trans

state. Ultraviolet-light irradiation makes the azobenzene groups transform to the

cis

configuration

which greatly hinders amines in the uptake of CO

2

. The caused difference of adsorpti

on capacity can reach 34.9%. The alternative irradiation by ultraviolet- and visible-light can lead to a recyclable regulation on adsorption performance. The changes of the electrostatic potentials of amines are responsible for the light-induced regulation on adsorption.