Differentiable Detection of Volatile Amines with a Viologen-Derived Metal–Organic Material

Abstract

The development of selective sensing materials for amine detection has received considerable attentions because amines have high toxicity and exist widely. In this article, we demonstrate for the first time that a degree of discriminative detection of alkylamines can be achieved by a metal-organic coordination material. The material is derived from Cd and 4,4'-bipyridinium-1,1'-bis(phenylene-3-carboxylate), shows 1D channels lined with electron-deficient viologen chromophores, and exhibits different colors upon contact with amine vapors of different molecular sizes and types (primary, secondary, and tertiary). The vapochromism is attributable to electron transfer from the amine group to viologen. The discrimination between amines is because the analyte-receptor interactions, which either directly mediate or indirectly affect electron transfer, are influenced by the number of the N-H bonds in the amine molecule, the size of the amine molecule relative to the receptor channel and the steric hindrance for the electron donor-acceptor contacts. The material also shows reversible photo- and hydrochromism owing to stimuli-induced reversible electron transfer. The compound can be deposited in paper simply by spraying the mixture solution of the starting metal salt and the ligand. The paper can be used as portable test strips for visual and differentiable detection of amines and as erasable inkless printing medium.

A single-crystal-to-single-crystal transformation affording photochromic 3D MORF crystals

“…S4, supporting information). 25,32 Previous reports suggest that the carboxylic acid functions are the electron donors in photoswitchable MOFs, 25-26, 26d, 28c, 33 but more investigations are needed to ascertain the nature of the electron donor in this case.…”

A Solid-State Luminescent Cd(II) Supramolecular Coordination Framework Based on Mixed Luminophores as a Sensor for Discriminatively Selective Detection of Amine Vapors

“…Compound 1 is not sensitive to the common VOCs and the emission bands of the samples did not undergo any changes (Figure S5). Thus, 1 can be only considered as an efficient chemical sensor for NH 3 and EDA detection. To the best of our knowledge, the shift of emission bands in this work is the largest spectral change for NH 3 and EDA detections.…”

Sonochemical synthesis of a trinuclear Cu(ii) complex with open coordination sites for the differentiable optical detection of volatile amines

“…13,14 Since Lewis basic amines are poisonous and corrosive compounds, they can be easily absorbed and endanger human safety and the environment. 15,16 There are many techniques for amine detection such as high-performance liquid chromatography, gas chromatography coupled with mass spectrometry, uorometric analysis, and electrochemical systems. However, these techniques not only require skilled operation and long analysis time but are also complicated, expensive, and not readily available on-site in most cases.…”