Direct CO2 capture from simulated and ambient air over silica-rich MIL-101(Cr)

RHA-MIL-101(Cr) captures 2.4 times more CO 2 (1.06 mmol g −1 ) than MIL-101(Cr) (0.45 mmol g −1 ) with faster kinetics (80 min) and high cyclic stability, attributed to higher surface area (47%) and ultramicropore volume (16%) due to the incorporation of RHA.