Highly Temperature-Sensitive CO2 Gate Adsorption on a Flexible 1D Metal-Organic Framework Functionalized with (Trifluoromethyl)trifluoroborate Anion.

A newly synthesized one-dimensional (1D) metal-organic framework (MOF) functionalized with the (trifluoromethyl)trifluoroborate anion was characterized by single-crystal X-ray diffraction, thermogravimetric analysis, CHN elemental analysis, Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy, and gas adsorption and separation experiments. The 1D MOF exhibits gate-type CO2 adsorption isotherms in the temperature range of 263-303 K with rectangular hysteresis loops. The CO2 gate-adsorption pressure is strongly temperature dependent, and this dependence is relatively large compared with those of other MOFs that exhibit a similar behavior. This property, which is associated with the structural flexibility of the material, makes the studied system particularly promising for carbon dioxide capture and separation by exploiting the temperature swing adsorption (TSA) technique.