Wobbling and Hopping: Studying Dynamics of CO2 Adsorbed in Metal–Organic Frameworks via 17O Solid-State NMR
mediaposted on 17.12.2015, 04:54 by Wei David Wang, Bryan E. G. Lucier, Victor V. Terskikh, Wei Wang, Yining Huang
Knowledge of adsorbed gas dynamics within microporous solids is crucial for the design of more efficient gas capture materials. We demonstrate that 17O solid-state NMR (SSNMR) experiments allow one to obtain accurate information on CO2 dynamics within metal–organic frameworks (MOFs), using CPO-27-M (M = Mg, Zn) as examples. Variable-temperature (VT) 17O SSNMR spectra acquired from 150 to 403 K yield key parameters defining the CO2 motions. VT 17O SSNMR spectra of CPO-27-Zn indicate relatively weaker metal–oxygen binding and increased CO2 dynamics. 17O SSNMR is a sensitive probe of CO2 dynamics due to the presence of both the quadrupolar and chemical shielding interactions, and holds potential for the investigation of motions within a variety of microporous materials.