All-in-one type ESIPT-active multi-stimuli responsive 7-diethylamino-4-hydroxycoumarin-rhodamine B hydrazone as molecular switches and the reversible photochromic features of its zinc ensemble

Abstract

Multi-stimuli responsive fluorescent materials have vast applications in the field of chemistry, physics, and material science. Among the multifunctional materials, ESIPT-active materials have drawn prodigious attraction in recent years due...

A Brief Review on Advances in Rhodamine B Based Chromic Materials and Their Prospects

“…However, the Zn 2+ -coordinated ligand exhibited excellent photochromism. The group echoed the MG-ESIPT (Figure B) (as suggested by Professor Chowdhury et al) as the probable mechanism for the photochromic process …”

“…The group echoed the MG-ESIPT (Figure 24B) (as suggested by Professor Chowdhury et al) as the probable mechanism for the photochromic process. 50 In 2022, Prof. P. Chowdhury's group designed and developed another new metal-guided photochromic system (MG-PCS) based on RhB salicylaldehyde hydrazone Zn− metal complex 51 (Figure 25A and B). All the photochromic properties including photostationary state, fatigue resistance, 48−51,62,64−66 ESIPT may be considered as a four-level photophysical process, as shown in Figure 26.…”

“…Among the three, the metal complex-based photochromic materials are very recent. Particularly, RhB-based photochromic metal complexes are very interesting because they give rise to fantastic characteristic properties under the guidance of a coordinating metal. − …”

“…The photochromic phenomenon observed (2013–2022) involves mainly the excited-state intramolecular proton transfer (ESIPT). In the 1950s, Weller first proposed the ESIPT, − which involves photoinduced tautomerism. − ,,− ESIPT may be considered as a four-level photophysical process, as shown in Figure . The presence of suitable metal ions (e.g., Zn 2+ ) is essential to display the ESIPT.…”

Systematic photophysical, thermal and electrochemical analysis of a series of phenothiazine cored conjugated aromatic unit appended D–π–A based high-solid state luminescent materials: their applications in reversible mechanofluorochromic and volatile acid sensing

“…[11][12][13][14][15] Compared to metal-based MFC materials, which suffer from commercialization challenges owing to the high price and the toxicity of noble metals, organic compounds turn out to be favorable alternatives due to their facile synthetic strategy. These types of materials have attracted special attention from researchers because of their bright potentiality in security inks, 16 3D printing, 17,18 memory chips, 19 and mechanosensors 20,21 as they are susceptible to shearing, pressing, ball milling, and grinding, causing a variation in the fluorescence emission color.…”