Functionalized stellate macroporous silica nanospheres for CO2 mitigation

Abstract

Carbon capture represents an integral part of the CO2 mitigation efforts, and involves the demonstration of effective and inexpensive CO2 capture technologies. We report the first demonstration of an amine-functionalized stellate macroporous silica as a platform for effective CO2 absorption, with potential application in current fossil-fuel burning plants. The work demonstrates that the facile impregnation of the silica platform with tetraethylenepentamine results in a high-performing sorbent for carbon dioxide. The CO2 absorption data exceed the performance of other reported silica–amine matrices for carbon capture, showing an amount of over 4 mmol CO2/g sorbent at low temperature, simulating the flue gas temperature. The platform is robust, showing recyclability and >85 % mass conservation of sorbent upon nine cycles. In addition, the stellate MSNs show high CO2 selectivity at room temperature, indicating that the presence of nitrogen in flue gas will not impair the CO2 absorption performance. The results could lead to a simple and inexpensive new technology for CO2 mitigation.