Recent progress in polyoxometalate–viologen photochromic hybrids: structural design, photochromic mechanism, and applications

Abstract

Polyoxometalate–viologen hybrids are a class of photochromic materials with variable structure and interesting application performance. In recent years, some progress has been made in polyoxometalate–viologen photochromic hybrids through rational structural...

A Series of POM–Viologen Photo-/Electrochromic Hybrids and Hydrogels Acting as Multifunctional Sensors for Detecting UV, Hg2+, and Organic Amines

“…As a new kind of intelligent material, photochromic materials have important applications in the fields of information encryption, optical information storage, photoelectric materials, optical switches, and optical devices . Electron-deficient viologen derivatives (1,1′-disubstituted 4,4′-bipyridiniums), as good photochromic materials, are widely used in ink-free erasable printing, UV detection, and other fields. − It is because of its electron-deficient nature that it can form charge transfer complexes with electron-rich species and has the redox capability of reversible electron transfer under the stimulation of an external environment, such as light. − Therefore, the combination of viologen and multielectron species can construct more color-changing materials with excellent properties.…”

An iron-containing POM-based hybrid compound as a heterogeneous catalyst for one-step hydroxylation of benzene to phenol

“…Polyoxometalates (POMs), as a class of inorganic metal oxide clusters with a rich structure and excellent redox properties, have attracted broad attention in the fields of catalysis, optics, magnetism, etc . 20–32 Among numerous POM-based materials, molybdovanadophosphoric acid (PMoV) with the Keggin structure has attracted the attention of a wide range of researchers. Since this form of polyacid has abundant and variable metal valence states, it can activate molecular oxidation to obtain reactive oxygen species and easily selectively oxidize reactive organic substrates without the addition of reducing agents.…”

The effect of conjugation degree of aromatic carboxylic acids on electronic and photo-responsive behaviors of naphthalenediimide-based coordination polymers

“…Organic–inorganic hybrid photochromic systems composed of electron donors (EDs) and electron acceptors (EAs) have attracted a great degree of scientific attention due to their exceptional photo-responsive characteristics (instantaneous photo-responsive rate, wide photo-responsive range and intense coloration contrast) and wide range of application prospects in data storage, optical switches, sensors, protection, inkless printing and so forth. 1–17 Some extraordinary achievements have been made in organic–inorganic hybrid photochromic materials through ingenious structural design. 18–21 Especially, the photochromic performances in terms of photo-responsive rate, photo-response range and coloration contrast of these hybrids have been optimized by rational selection and masterly integration of EDs and EAs as well as effectively modulating intermolecular electronic behaviors.…”