Evolution of Transient Luminescent Assemblies Regulated by Trace Water in Organic Solvents

Abstract

Trace water in organic solvents can play a crucial role in the construction of supramolecular assemblies, which has not gained enough attention until very recent years. Herein, we demonstrate that residual water in organic solvents plays a decisive role in the regulation of the evolution of assembled structures and their functionality. By adding Mg(ClO 4 ) 2 into a multi-component organic solution containing terpyridine-based ligand 3Tpy and monodentate imidazole-based ligand M2, the system underwent an unexpected kinetic evolution. Metallo-supramolecular polymers (MSP) formed first by the coordination of 3Tpy and Mg 2+ , but they subsequently decomposed due to the interference of M2, resulting in a transient MSP system. Further investigation revealed that this occurred because residual water in the solvent and M2 cooperatively coordinated with Mg 2+ . This allowed M2 to capture Mg 2+ from MSP, which led to depolymerization. However, owing to the slow reaction between trace water/M2/Mg 2+ , the formation of MSP still occurred first. Therefore, water regulated both the thermodynamics and kinetics of the system and was the key factor for constructing the transient MSP. Fine-tuning the water content and other assembly motifs regulated the assembly evolution pathway, tuned the MSP lifetime, and made the luminescent color of the system undergo intriguing transition processes over time.

Lead-Free Antimony-Based Perovskite Nanocrystals as a Fluorescent Nanoprobe for the Turn-On Detection of Trace Water in Organic Solvents

“…The excited-state fluorescent molecules are more inclined to interact with polar solvents, which results in a redistribution of the electron density of the solvent. Consequently, this will lead to a decrease in the energy level of the fluorophores in the excited state. , Hence, an alteration in the polarity of the solvent will affect the fluorescence intensity of the fluorophores as well. Significant variations in the fluorescence intensities are observed when the same volume of different polarity solvents, including water, acetone, DCM, and octane, is added to Cs 3 Sb 2 Br 9 PNCs (Figure B).…”

Chiral supramolecular nanomaterials: From chirality transfer and amplification to regulation and applications

“…In a CHCl 3 /THF solution, Zhang et al reported a temporary assembly mechanism where the development of structure and luminescence of assemblies is controlled by small amounts of water. [ 39 ] By manipulating the moisture content and implementing alternative assembly configurations, the system can exhibit various evolutionary pathways, control the lifespan of supramolecular polymers, and modify the temporal luminescent properties of the system.…”

Water-Regulated Evolution of Inversion, Reinversion, and Amplification of Circularly Polarized Luminescence of Supramolecular Organogels Based on Glutamide–Cyanostilbene Amphiphile

“…The nature of the solvent might significantly affect the CPL and CD performance of chiral self-assembled systems in solution due to complex interactions between solvents and solutes, − which makes the role of the solvent as the part of supramolecular entities more prominent . In particular, molecular water plays an important role in the construction and stabilization of natural or man-made assemblies and their functionality. ,− Chirality transitions at low temperatures were observed upon the incorporation of monomeric water molecules into supramolecular polymers of biphenyl tetracarboxamide .…”