Multistimuli-responsive materials based on a zinc() complex with high-contrast and multicolor switching

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 51; no. 4; pp. 1537 - 15375
• Main Authors: Zheng, Han-Wen, Yang, Dong-Dong, Shi, Yong-Sheng, Xiao, Tong, Zheng, Xiang-Jun
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 18.10.2022
• Subjects: Absorption spectra; Ammonia; Crystal surfaces; Electrochemical oxidation; Gas-solid reactions; Mechanoluminescence; Phase transitions; Stimuli; Switching; Zinc compounds
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d2dt02435g

The development of stimulus-responsive luminescent materials, especially those based on a single compound exhibiting multicolor and high-contrast (Δ λ em ≥ 100 nm) chromic properties, is a critical challenge. In this work, we synthesized and characterized a zinc( ii ) complex ( 1 ). As expected, 1 displays aggregation-induced emission enhancement (AIEE) in THF/H 2 O mixtures, and remarkable multicolor switching under external stimuli in the solid state. Complex 1 shows reversible mechanochromic luminescence behavior with a large wavelength shift (Δ λ em = 100 nm) during the grinding-fuming cycles, due to the phase transformation between the crystalline and amorphous states. More impressively, 1 exhibits obvious acidochromic properties (Δ λ em = 130 nm) which originate from the adsorption of vapor and a gas-solid reaction on the crystal surface. Furthermore, 1 exhibits electrochemical oxidation behavior accompanied by quenching of yellow-green emission due to the overlap of an emission band and an absorption band. The above-mentioned color changes under ambient light can also be observed by the naked eye during the mechanical, acid-base vapor and electrical stimulation. Based on the high-contrast and multicolor switching, complex 1 was successfully developed into test papers and films in the field of rapid detection of mechanical stimuli and HCl/NH 3 vapors. A zinc( ii ) complex exhibits high-contrast and multicolor switching in response to mechanical, acid-base vapor and electrical stimulation under ambient light and 365 nm UV light.