Jump to main content
Jump to site search


Encapsulation of stilbazolium-type dyes into layered metal–organic frameworks: solvent-dependent luminescence chromisms and their mechanisms

Author affiliations

Abstract

The incorporation of organic dyes into host matrices has attracted great interest for developing new functional materials. In this work, two Cd-based layered metal–organic complexes (Cd-LMOCs), i.e. [Cd3(BTB)2(DEF)4]n, (1-DEF) and [Cd3(BTB)2(DMF)4·2DMF]n, (2-DMF), were synthesized, and three different organic stilbazolium-type dyes were incorporated into the layered Cd-LMOCs: CMAS+, which contains an electron-withdrawing group (–CN) on the amine, and DAST+ and HMAS+, which contain electron-donating groups (–CH3, –OH) on their amines. Interestingly, solvent-dependent luminescence chromisms were observed; these only occurred in DMA solvent. The dye@Cd-MOC composites obtained from DMA solvent have been fully characterized by IR, UV-Vis, PXRD, SEM, TEM and TGA; they exhibit blue-shift photoemissions and enhanced quantum yields compared with the pristine Cd-LMOCs and dye samples. After loading with dyes, the photocurrents were diminished by 2 to 6 times. Based on a combination of experimental and theoretical simulations of the dye@Cd-LMOC systems, a two-step solvent-dependent chromism mechanism was proposed: solvent exchange reactions occur firstly, and the dyes then enter the Cd-LMOCs via direct or semi-coordinated bonds between the Cd centers and guest dyes. Specifically, (CMAS)I@1-DMA with direct Cd–N bonds exhibits the highest quantum yield, and a new electron transfer route from the metal centers of the host skeletons to the side groups of the guest dyes has been found. In all, the introduction of electron-withdrawing groups on dyes is beneficial for host–guest interactions.

Graphical abstract: Encapsulation of stilbazolium-type dyes into layered metal–organic frameworks: solvent-dependent luminescence chromisms and their mechanisms

Back to tab navigation

Supplementary files

Publication details

The article was received on 11 Dec 2018, accepted on 18 Mar 2019 and first published on 19 Mar 2019


Article type: Research Article
DOI: 10.1039/C8QI01332B
Citation: Inorg. Chem. Front., 2019, Advance Article

  •   Request permissions

    Encapsulation of stilbazolium-type dyes into layered metal–organic frameworks: solvent-dependent luminescence chromisms and their mechanisms

    L. Zhao, X. Shen, L. Tan, W. Zhang, K. Song, R. Jiang, H. Li and Z. Chen, Inorg. Chem. Front., 2019, Advance Article , DOI: 10.1039/C8QI01332B

Search articles by author

Spotlight

Advertisements