title: Postsynthetic modification of a metal-organic framework for stabilization of a hemiaminal and ammonia uptake.
abstract: In our study, we show by solid-state (15)N NMR measurements that an important zirconium metal-organic framework (UiO-66) with amino-functionalized links is composed of a mixture of amino and -NH(3)(+)Cl(-) salt functionalities rather than all amino functionality to give a composition of Zr(6)O(4)(OH)(4)(BDC-NH(2))(4)(BDC-NH(3)(+)Cl(-))(2) (UiO-66-A). UiO-66-A was postsynthetically modified to form a mixture of three functionalities, where the hemiaminal functionality is the majority species in UiO-66-B and aziridine is the majority functionality in UiO-66-C. UiO-66-A-C are all porous with surface areas ranging from 780 to 820 m(2)/g and have chemical stability, as evidenced by reversible ammonia uptake and release showing capacities ranging from 134 to 193 cm(3)/g.
authors.affiliation: Center for Reticular Chemistry, University of California, 607 Charles E. Young Dr. East, Los Angeles, California 90095, USA.
authors.forename: William
authors.initials: W
authors.lastname: Morris
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Doonan
authors.forename: Omar M
authors.initials: OM
authors.lastname: Yaghi