Currently, CO 2 is captured at power plants by passing the flue gas over a solution of liquid monoethanolamine. The liquid is corrosive, forms toxic by-products and must be heated to high temperatures to recover the CO 2 and regenerate the solvent. Jennifer Lewis at Harvard University in Cambridge, Massachusetts, and her colleagues created microcapsules made of a highly porous silicone skin containing a carbonate solvent. These solvents absorb CO 2 slowly, but encapsulation of solvent boosts the absorption rate tenfold (compared to pools of liquid carbonate) by increasing the surface area.

Credit: John Vericella, Roger Aines (LLNL); Jennifer Lewis (Harvard)