Nanoparticles of MIL-101(Cr) have been fabricated using a hydrothermal method for the first time. The particle size can be controlled from 19 (4) nm to 84 (12) nm, by using a monocarboxylic acid as a mediator. These nano MIL-101(Cr) materials exhibit higher selectivities for CO2 over N2 than bulk MIL-101(Cr).
