Atmospheric carbon dioxide capture by adsorption on amine-functionalized silica composites: a review

The rising negative effects of climate change are caused mainly by the increase of atmospheric carbon dioxide concentrations, calling for advanced technologies to extract carbon dioxide from atmospheric air. Here we review carbon dioxide capture from atmospheric air by amine-functionalized silica composites with emphasis on development principles, mechanisms, absorbent criteria, performance determination, and preparation techniques. Amine-silica absorbent preparation for carbon dioxide capture is done by impregnation, chemical graphting, hybrid functionalization, and in situ polymerization. High costs, poor performance, and scalability are actually posing challenges for large-scale deployment.