In the present lecture, I will discuss about the recent progresses on the development of low-temperature CO2 adsorbent. The adsorbent is based on the polyethyleneimine impregnated on the mesopores of silica support. In contrast to many related adsorbents in literatures, our adsorbents showed markedly high working capacity (~10 wt%) as well as outstanding recyclability due to the complete switch-off of urea formation under desorption condition.