A multi-stimuli electron-transfer supramolecule with segregated-stacking donor-acceptor within the lattice exhibting photo- and thermochromic, sensitive detection for amines

Planar Viologen-Based Crystalline Compounds Showing Heat-Induced Electron Transfer and Thermochromism

“…To probe the δ-dependent heat-induced ET behavior of viologen compounds, we summarized all known viologen compounds with definite crystal structures that showed thermochromism or heat-induced color change (Tables and ). − As can be seen in Tables and and Figure S1, the probability to undergo thermochromism or heat-induced color change is higher for viologens with small δ values than for ones with large δ values, although the reported coloration temperatures are different. Heating temperature, undoubtedly, has a great effect on heat-induced ET for viologen compounds.…”

Two multifunctional stimuli-responsive materials with room-temperature phosphorescence and their application in multiple dynamic encryption

“…As is known that amines seriously endanger human health and environmental safety, the rapid detection of amines is still a huge challenge. [41][42][43] Here, we selected 1 as a portable sensor to investigate the response to five amines (NH 3 , ethylamine (EA), propylamine (PA), butylamine (BA), and aniline (AN)). As shown in Fig.…”

One-Dimensional Chain Viologen-Based Lanthanide Multistimulus-Responsive Materials with Photochromism, Photoluminescence, Photomagnetism, and Ammonia/Amine Vapor Sensing

“…In consideration of the intrinsic electron-deficient viologen complexes, which normally respond actively to inorganic ammonia/organic amines that are rich in electrons. ,,,− As expected, 1-Dy displayed distinctly different color responses under different ammonia/amine vapor atmospheres in the presence of inorganic ammonia: NH 3 , hydrazine hydrate (N 2 H 4 ·H 2 O), primary amine: ethylamine (EA), ethylenediamine (EDA), and secondary amine: diethylamine (DEA), exhibiting cyan, light-green, navy blue, dark blue, and yellow (Figure a), respectively. This reflects the discrimination on the primary amines and secondary amines, while neither tertiary amine: triethylamine (TEA) vapor nor the TEA aqueous solutions make 1-Dy change color.…”

“…In addition, the visible color difference can be detected when the materials are fumigated in ammonia/amine molecules with different steric hindrance substituents, which is consistent with few viologen-based metal−organic coordination materials. 60,63 Tertiary amines such as TEA have three alkyl substitutes on the nitrogen atom possessing bigger steric hindrance, which possibly prevents the electron-rich group not easily make contact with the electron-deficient bipyridyl phase. As a result, electron transfer is hardly triggered and cannot lead to color change.…”

“…Generally, the IR spectrum of the amine-treated sample after coloration should show characteristic peaks at about 3300− 3500 and 2750−2950 cm −1 assigned to amino ν N−H and/or alkyl ν C−H (existing in an amine group) absorption for adsorbed amines, respectively. 60 However, they may be masked by the hydrogen bonding vibration absorptions and ν C−H absorptions derived from the presence of lattice water, coordination water, and the existing alkyl chain in viologen propionic acid. Even so, the IR spectrum of an amine-treated sample displayed more broad peaks around 3000−3500 cm −1 , which may be due to the formation of new hydrogen bonds involving S21).…”