Hydrolysis controlled synthesis of amine-functionalized hollow ethane–silica nanospheres as adsorbents for CO2 capture

Bifunctionalized organosilica hollow nanospheres with bridging ethane group and protruding amine group have been successfully synthesized through prehydrolysis strategy using 3-(aminopropyl)triethoxysilane (APTES) and 1,2-bis(trimethoxysilyl)ethane (BTME) as precursor and F127 (EO106PO70EO106) as a single micelle template in a neutral medium. It was found that prehydrolysis of BTME could efficiently decrease the interruption of amine group on the assembly process and result in the formation of uniform hollow nanospheres with particle size in 15–18 nm. This general synthetic strategy has been extended to the preparation of functionalized hollow nanospheres with different functional groups, such as N-propyl-4,5-dihydroimidzole and di-propyl-amine group. These amine-functionalized hollow nanospheres are efficient adsorbents for CO2. The controlling experiments suggest that both the hollow structure and amine group are responsible for obtaining high CO2 adsorption capacity.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Amine-functionalized hollow nanospheres were synthesized through prehydrolysis. ► Hollow nanospheres with different functional groups were synthesized. ► These amine-functionalized hollow nanospheres are efficient adsorbents for CO2. ► Both amine loading and morphology have a corporative action in the sorption of CO2.