Zinc tungstate encapsulated into a scarce Zn(ii)–viologen framework with photochromic, electrochromic and chemochromic properties

Abstract

Smart chromic materials with physicochemical stimuli were widely applied in optical switches, smart windows, and chemical sensors. Currently, most materials only respond to a single stimulus, but those with multiple...

Four Chromic Compounds Constructed from Keggin Polyoxometalates and Viologens with Applications in Ultraviolet, Metal Ion Detection, and Ink-Free Printing

“…Specifically, 1 -ECD has obvious absorption peaks at 614 and 671 nm, 2 -ECD at 472 and 607 nm, 3 -ECD at 485 and 603 nm, and 4 -ECD at 496 and 610 nm. Therefore, we speculate that the electrochromic process may also produce viologen free radicals . Combined with the test results of the ultraviolet spectrum, EPR, and XPS, the discoloration of four compounds under light and electric stimulation is due to electron transfer, which produces viologen free radicals.…”

“…Therefore, we speculate that the electrochromic process may also produce viologen free radicals. 44 Combined with the test results of the ultraviolet spectrum, EPR, and XPS, the discoloration of four compounds under light and electric stimulation is due to electron transfer, which produces viologen free radicals. Figure S18 shows a schematic diagram of the discoloration mechanism taking compound 1 as an example.…”