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A novel chiral fluorescent probe, tetraphenylvinyltriazole-ribosyl ribose derivative (β, D)-RIB-TPE, was prepared by Click reaction. It can self-assemble into amphiphilic micron vesicles in methanol solution. (β, D)-RIB-TPE has good AIE properties with a large Stokes shift (redshift 61.8 nm), self-assembles into J-aggregates in a mixed solution with 98% water content, and exhibits a relative fluorescence intensity αAIE = 24, emitting bright blue fluorescence. In addition to the micron vesicles, (β, D)-RIB-TPE self-assembled into J-aggregates in different mixtures, showing different morphologies, such as a cross-linked network structure and an irregular bulk stacking structure. The fluorescent probe (β, D)-RIB-TPE could achieve high efficiency and rapid multi-channel detection of clopidogrel S-(+)-sulfate by fluorescence chromatography and CD spectroscopy. Infrared, nuclear magnetic titration, scanning electron microscopy and DFT calculations confirmed that the probe (β, D)-RIB-TPE recognized S-(+)-clopidogrel sulfate by an ICT mechanism. (β, D)-RIB-TPE and S-(+)-clopidogrel sulfate were co-assembled in methanol to form single-target drug-carrying micron vesicles with a smaller particle size than the self-assembled (β, D)-RIB-TPE vesicles and good drug embedding capacity. [ABSTRACT FROM AUTHOR]

In this paper, two aggregation-induced emission (AIE) chiral fluorescent materials, S-1 and S-2, were synthesized. The two materials are based on BINOL and H8-BINOL backbones, respectively, and large electron-absorbing groups are attached to the chiral backbones through the Knoevenagel reaction. At the same time, the CD signals of these two chiral fluorescent materials are gradually weakened (fw gradually increases) as they continue to aggregate. However, S-2 underwent a flip-flop from a negative to positive chiral CD signal at fw ≥ 90. And both materials also showed significant enantioselective recognition of lysine, demonstrating their potential as novel chiral fluorescent probes. Among them, the enantioselective fluorescence enhancement ratios (ef) of S-1 and S-2 for lysine were 10.0 and 10.3, respectively, while different degrees of blue shifts were produced by the ICT mechanism during the recognition process. In addition, the self-assembled morphology of the two nanomaterials is different; S-1 comprises hollow-core vesicles that are more likely to aggregate to form larger self-assembled vesicles, whereas S-2 is a solid block structure. When L/D-lysine was added alone, the morphology of S-1 was more distinctly different compared to S-2. With the addition of L-lysine, S-1 was dispersed and regularly spherical, whereas with the addition of D-lysine, S-1 itself remained in the form of aggregated large vesicles. This suggests that both S-1 and S-2 are important in the fields of chiral optics, chiral recognition, and nanoscale self-assembly. [ABSTRACT FROM AUTHOR]

The chiral H8-BINOL derivatives R-1 and R-2 were efficiently synthesized via a Suzuki coupling reaction, and they can be used as novel dialdehyde fluorescent probes for the enantioselective recognition of R/S-2-amino-1-phenylethanol. In addition, R-1 is much more effective than R-2. Scanning electron microscope images and X-ray analyses show that R-1 can form supramolecular vesicles through the self-assembly effect of the π-π force and strong hydrogen bonding. As determined via analysis, the fluorescence of the probe was significantly enhanced by mixing a small amount of S-2-amino-1-phenylethanol into R-1, with a redshift of 38 nm, whereas no significant fluorescence response was observed in R-2-amino-1-phenylethanol. The enantioselective identification of S-2-amino-1-phenylethanol by the probe R-1 was further investigated through nuclear magnetic titration and fluorescence kinetic experiments and DFT calculations. The results showed that this mechanism was not only a simple reactive probe but also realized object recognition through an ICT mechanism. As the intramolecular hydrogen bond activated the carbonyl group on the probe R-1, the carbonyl carbon atom became positively charged. As a strong nucleophile, the amino group of S-2-amino-1-phenylethanol first transferred the amino electrons to a carbonyl carbocation, resulting in a significantly enhanced fluorescence of the probe R-1 and a 38 nm redshift. Similarly, S-2-amino-1-phenylethanol alone caused severe damage to the self-assembled vesicle structure of the probe molecule itself due to its spatial structure, which made R-1 highly enantioselective towards it. [ABSTRACT FROM AUTHOR]

Despite the great progress has been made on device parameters and working mechanism of perovskite‐based memristors, thermal instability under extreme conditions limits their performance, and thermal effect on their resistive switching (RS) characteristics remains unclear. Herein, from the viewpoint of organic/inorganic interfacial interaction in a novel 2D <100>‐oriented perovskite [(TZ‐H)2(PbBr4)]n (TZ = 1H‐1,2,4‐triazole), thermal effect on the RS performance of perovskite‐based memristor is investigated. This FTO/[(TZ‐H)2(PbBr4)]n/Ag memristor can exhibit high thermal tolerance with a working temperature of 170 °C, and the best RS characteristics can be achieved at 140 °C. Mechanistic studies are executed based on X‐ray single structural analysis, powder X‐ray diffraction, UV–Vis, and fluorescence. Before the occurrence of phase change below 140 °C (α‐phase), anisotropic lattice expansion illustrated by the weaker inter‐layer NH···Br hydrogen bond, longer layer–layer distances, more distorted PbBr6 octrahedra, larger optical gap, and quenched fluorescence can be beneficial for the trap‐filled limited process. After phase transformation into β‐phase, the breakage of layer–layer interaction and looser layer–layer packing will inhibit the halogen migration, resulting in more space charge limited conduction characters. The unique thermal enhanced RS performance with status monitored by fluorescent chromism can provide a new paradigm for the development of new memristors with highly environmental tolerance. [ABSTRACT FROM AUTHOR]

R - BTOBD exhibited significant aggregation-induced Emission (AIE) characteristics, including high brightness (αAIE ≈ 40), robust light stability, a substantial Stokes shift (128 nm), and a high signal-to-noise ratio, effectively overcoming aggregation-caused quenching (ACQ). Derived from the axially chiral R -H 8 -BINOL, R - BTOBD was synthesized via nucleophilic cyclization and exhibited pronounced self-assembly properties. Through robust intra- and intermolecular hydrogen bonding interactions, R - BTOBD formed diverse supramolecular structures, including spherical flower-like aggregates, hollow-core triangular tubules, hexagonal tubules, and irregular white block-like stacks. The specific morphology was influenced by factors such as solvent and pH. For fluorescence applications, R - BTOBD can be employed as an effective visual pH detector through an AIE-enhanced excited-state intramolecular proton transfer (AIE-ESIPT) mechanism. When incorporated into pH paper, it exhibited a bright yellow fluorescence across a wide pH range (pH 1-11), transitioning to an intense bright blue fluorescence under strongly basic conditions (pH 12-14). In chiral applications, R - BTOBD demonstrated potential as a chiral switching agent, leveraging the pronounced changes and inversions in its circular dichroism (CD) signals under varying aggregation states and pH conditions. Additionally, it serves as a specific chiral enantioselective fluorescence probe for l-lysine, demonstrating high efficiency and a low detection limit. Given its exceptional fluorescence and chiral properties, this fluorescent material has significant potential for diverse applications in fluorescence, chirality, and visual inspection.