Versatile and Switchable Responsive Properties of a Lanthanide‐Viologen Metal–Organic Framework

Metal–organic frameworks (MOFs) provide intriguing platforms for the design of responsive materials. It is challenging to mobilize as many components as possible of a MOF to collaboratively accomplish multiple responsive properties. Here, reversible photochromism, piezochromism, hydrochromism, ionoc...

Full description

Saved in:
Bibliographic Details
Published in:Small (Weinheim an der Bergstrasse, Germany) Germany), 2019-02, Vol.15 (5), p.e1803468-n/a
Main Authors: Gong, Teng, Sui, Qi, Li, Peng, Meng, Xian‐Fu, Zhou, Li‐Jiao, Chen, Jinquan, Xu, Jianhua, Wang, Lin, Gao, En‐Qing
Format: Article
Language:English
Subjects:
Anion exchanging
Bonding strength
Cation exchanging
Charge transfer
Chemical sensors
Electron transfer
Electrons
Energy transfer
Logic circuits
Luminescence
luminescence switches
Metal-organic frameworks
Nanotechnology
Organic chemistry
Photochromism
piezochromism
Polarity
Pressure sensors
Properties (attributes)
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Metal–organic frameworks (MOFs) provide intriguing platforms for the design of responsive materials. It is challenging to mobilize as many components as possible of a MOF to collaboratively accomplish multiple responsive properties. Here, reversible photochromism, piezochromism, hydrochromism, ionochromism, and luminescence modulation of an ionic Eu(III) MOF is reported furnished by cationic electron‐deficient viologen units and exchangeable guest anions. Mechanistically, the extraordinarily versatile responsive properties are owed to electron transfer (ET), charge transfer (CT), and energy transfer, involving viologen as electron acceptor, anion as electron donor, luminescing Eu(III) as energy donor, and anion‐viologen CT complex or ET‐generated radical as energy acceptor (luminescence quencher). Moreover, guest anions and waters provide flexible handles to control the ET‐based responsive properties. Water release/reuptake or exchange with organic solvents can switch on/off the response to light, while reversible anion exchange can disenable or awaken the responses to pressure, light, and water release/reuptake. The impacts of water and anions on ET are justified by the high polarity and hydrogen‐bonding capability of water, the different electron donor strength of anions, and the strong I−‐viologen CT interactions. The rich responsive behaviors have great implications for applications such as pressure sensors, iodide detection, and chemical logic gates. All components (metal, ligand, guest anion, and solvent) of the ionic metal–organic framework are mobilized to participate in stimuli‐induced electron transfer, charge transfer, or energy transfer, resulting in reversible piezochromism, hydrochromism, photochromism, ionochromism, and concomitant luminescence quenching. The responsive properties can be switched on/off through anion and solvent exchange.
ISSN:1613-6810
1613-6829
DOI:10.1002/smll.201803468