TY - JOUR
T1 - Guest-Anion-induced rotation-restricted emission in UiO-66-NH2and advanced structure elucidation
AU - Xue, Qi
AU - Chan, Ka Hin
AU - Yim, Cheuk Ki
AU - Ng, Bryan Kit Yue
AU - Chen, Tianxiang
AU - Day, Sarah J.
AU - Tang, Chiu
AU - Kawaguchi, Shogo
AU - Wong, Kwok Yin
AU - Lo, Tsz Woon Benedict
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (21902139) and the Hong Kong Research Grants Council (25300918 and 15300819) (T.W.B.L.). We thank SPring-8 (2018B1081) and UMF, UCEA, and ULS of HKPU for support with materials characterization.
Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/7/13
Y1 - 2021/7/13
N2 - We report the guest-anion-induced photoluminescence enhancement of metal-organic frameworks (UiO-66-NH2), first based upon diffraction and computational evidence. We found that only limited anions, namely, carbonate and fluoride, can lead to a significant enhancement in photoluminescence, whereas their related anions, such as acetate and chloride, cannot. The optimized crystal structures reveal that the guest carbonate and fluoride ions interact with four framework amino functional groups through hydrogen bonding (ca. 1.6-1.7 Å) that ultimately forms a quaternary (-N(H))4···X- molecular bridge around the nodal center. Hence, the hydrogen-bonded molecular bridge not only restricts the intermolecular C-C rotation of the linker molecules but also greatly perturbs the electronic densities between the guest anions and the framework amino groups.
AB - We report the guest-anion-induced photoluminescence enhancement of metal-organic frameworks (UiO-66-NH2), first based upon diffraction and computational evidence. We found that only limited anions, namely, carbonate and fluoride, can lead to a significant enhancement in photoluminescence, whereas their related anions, such as acetate and chloride, cannot. The optimized crystal structures reveal that the guest carbonate and fluoride ions interact with four framework amino functional groups through hydrogen bonding (ca. 1.6-1.7 Å) that ultimately forms a quaternary (-N(H))4···X- molecular bridge around the nodal center. Hence, the hydrogen-bonded molecular bridge not only restricts the intermolecular C-C rotation of the linker molecules but also greatly perturbs the electronic densities between the guest anions and the framework amino groups.
UR - http://www.scopus.com/inward/record.url?scp=85111008100&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.1c01674
DO - 10.1021/acs.chemmater.1c01674
M3 - Journal article
AN - SCOPUS:85111008100
SN - 0897-4756
VL - 33
SP - 5422
EP - 5429
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 13
ER -