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论文类型：期刊论文

发表时间：2017-08-30

发表刊物：JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

收录刊物：Scopus、SCIE、EI、PubMed

卷号：139

期号：34

页面范围：12020-12026

ISSN号：0002-7863

摘要：The predesigned metal-organic macrocycle Zn(3)QDB(3)(NO3)(4) (Zn-QDB) was observed to self-assemble into a hollow, spherical, single-layered "blackberry"-type structure. The self-assembly behaviors of the Zn-QDB are significantly influenced by additional small ions. Specifically, the cations exhibit strong co-ion effects on the interaction between cationic macrocycles which are different from the previously reported co-ion effects of simple anions on anionic polyoxometalates. This unusual phenomenon is due to the unique cation-pi interaction between small cations and electron-rich cavity of Zn-QPB, as confirmed by UV-vis, H-1 NMR, and fluorescence spectra. The variation of hydrodynamic radius (R-h) of assemblies with the changes of solution ionic strength and the, type of cations reveals the competition between counterion-mediated attraction and cation-pi interaction during the self assembly process. Furthermore, the cooperativity of cation-pi interaction and pi-pi stacking play a vital role in enhancing the stability of the supramolecular structure.