Tanlai Yu*, Le Cen, Yaxin Cheng, Guoshuai Zhang, Dayi Guo, Lei Wu, Xufeng Yang, Zhiyu Zhang, Cuilin Yang, Huan Zhang, Wenjiao Li, Yunlong Fu*, Jiang Liu*, Yong Yan*

Cite this article: Chin. J. Struct. Chem., 2026, 45(3), 100830. DOI: 10.1016/j.cjsc.2025.100830

Publication date: March 1, 2026

Keywords: Multicolor Photochromism; Electron donor-acceptor system; Iodoargentate hybridt; Lattice solvent-modulated; Erasable printing

ABSTRACT

Reversible multicolor photochromic materials based on electron donor-acceptor (EDA) systems have recently attracted considerable attention due to their potential applications in displaying, ink-free erasable printing and anti-counterfeiting. However, it is extremely challenging to realize multicolor photochromism by using same EDA system. Herein, a novel EDA iodoargentate hybrid, [(2-Bz-pyH)(Ag5I6)]·MeCN (1) (2-Bz-pyH+?= N-protonated 2-benzylpyridinium, MeCN = acetonitrile), has been obtained via solvent evaporation method at room temperature. Interestingly, upon ～ 365 nm Hg lamp irradiation, 1 and MeCN-desolvated 1 (denoted 1-H) display lattice solvent-modulated multicolor photochromic performance (pale yellow to brown for 1, yellow to reddish brown for 1-H) and fast response time (within 1 s). Additionally, 1-H was separately fumigated with DMF/DMSO/THF/DIOX vapors, and these samples also exhibit different photochromic properties under the same light conditions. Meanwhile, the new photochromic mechanism of intermolecular charge transfer composite with photolysis iodoargentate frameworks has been proposed through the combination of experimental and theoretical investigations. These results provide a new perspective for designing multicolor photochromic materials through lattice solvent-modulated same EDA system.