Purely organic room temperature phosphorescence (RTP) materials have aroused increasing interests in recent years and have been widely applied in anti‐counterfeiting, biological imaging, sensing, ...etc. Currently, these materials can be efficiently developed in crystalline states and amorphous polymer‐doped systems. However, achieving organic RTP in solution, especially in water solution, is still a formidable challenge. Recently, reports on aqueous phase RTP have been increasing and some feasible design strategies have been proposed; however, related investigations are still limited and there is a lack of systematic reviews. Therefore, we summarized the recent cases of aqueous phase organic RTP emission with primarily focusing on the RTP properties and efficient design strategies (e.g., forming nanoparticles from phosphorescent molecules and macrocyclic supramolecular assembly). Moreover, promising applications of the aqueous phase organic RTP emission in bio‐imaging and sensing were discussed. Some detailed perspectives concerning materials design and application were provided with the hope to provide inspiration for the future development of aqueous phase organic RTP.
Graphical . Purely organic room temperature phosphorescent (RTP) materials have aroused increasing interests; however, achieving aqueous phase organic RTP emission is still a formidable challenge. This review summarizes the recent advances of organic materials with RTP emission in aqueous solution, primarily focusing on the efficient design strategies and their promising applications in bio‐imaging and sensing, with the hope to provide inspiration for aqueous phase organic RTP materials.
Visualized sensing through fluorescence signals is a powerful method for chemical and physical detection. However, the utilization of fluorescent molecular probes still suffers from lack of precise ...signal self-calibration in practical use. Here we show that fluorescence and thermally activated delayed fluorescence can be simultaneously produced at the single-molecular level. The thermally activated delayed fluorescence serves as a sensing signal with its wavelength and lifetime both altered correlating to polarity, whereas the fluorescence always remains unchanged as an internal reference. Upon the establishment of a three-dimensional working curve upon the ratiometric wavelength and photoluminescence lifetime vs. polarity, disturbance factors during a relevant sensing process can be largely minimized by such a multiple self-calibration. This strategy was further applied into a precise detection of the microenvironmental polarity variation in complex phospholipid systems, towards providing new insights for convenient and accurate diagnosis of membrane lesions.
On the fluid drag reduction in scallop surface Li, Botong; Zhao, Zitian; Meng, Linyu ...
The European physical journal. E, Soft matter and biological physics,
2024-Jun-03, Letnik:
47, Številka:
6
Journal Article
Recenzirano
In the field of biomimetics, the tiny riblet structures inspired by shark skin have been extensively studied for their drag reduction properties in turbulent flows. Here, we show that the ridged ...surface texture of another swimming creature in the ocean, i.e., the scallops, also has some friction drag reduction effect. In this study, we investigated the potential drag reduction effects of scallop shell textures using computational fluid dynamics simulations. Specifically, we constructed a conceptual model featuring an undulating surface pattern on a conical shell geometry that mimics scallop. Simulations modeled turbulent fluid flows over the model inserted at different orientations relative to the flow direction. The results demonstrate appreciable friction drag reduction generated by the ribbed hierarchical structures encasing the scallop, while partial pressure drag reduction exhibits dependence on alignment of scallop to the predominant flow direction. Theoretical mechanisms based on classic drag reduction theory in turbulence was established to explain the drag reduction phenomena. Given the analogous working environments of scallops and seafaring vessels, these findings may shed light on the biomimetic design of surface textures to enhance maritime engineering applications. Besides, this work elucidates an additional evolutionary example of fluid drag reduction, expanding the biological repertoire of swimming species.
Graphical abstract
Lines used for shear stress data extraction of the shell model and the normalized wall shear of these lines on both models.
Lighting up solid states using a rubber Li, Zhongyu; Wang, Yanjie; Baryshnikov, Gleb ...
Nature communications,
02/2021, Letnik:
12, Številka:
1
Journal Article
Recenzirano
Odprti dostop
It is crucial and desirable to develop green and high-efficient strategies to regulate solid-state structures and their related material properties. However, relative to solution, it is more ...difficult to break and generate chemical bonds in solid states. In this work, a rubbing-induced photoluminescence on the solid states of ortho-pyridinil phenol family was achieved. This rubbing response relied on an accurately designed topochemical tautomerism, where a negative charge, exactly provided by the triboelectric effect of a rubber, can induce a proton transfer in a double H-bonded dimeric structure. This process instantaneously led to a bright-form tautomer that can be stabilized in the solid-state settings, leading to an up to over 450-fold increase of the fluorescent quantum yield of the materials. The property can be repeatedly used due to the reversibility of the tautomerism, enabling encrypted applications. Moreover, a further modification to the structure can be accomplished to achieve different properties, opening up more possibilities for the design of new-generation smart materials.
Utilization of ubiquitous low-grade waste heat constitutes a possible avenue towards soft matter actuation and energy recovery opportunities. While most soft materials are not all that smart relying ...on power input of some kind for continuous response, we conceptualize a self-locked thermo-mechano feedback for autonomous motility and energy generation functions. Here, the low-grade heat usually dismissed as 'not useful' is used to fuel a soft thermo-mechano-electrical system to perform perpetual and untethered multimodal locomotions. The innately resilient locomotion synchronizes self-governed and auto-sustained temperature fluctuations and mechanical mobility without external stimulus change, enabling simultaneous harvesting of thermo-mechanical energy at the pyro/piezoelectric mechanistic intersection. The untethered soft material showcases deterministic motions (translational oscillation, directional rolling, and clockwise/anticlockwise rotation), rapid transitions and dynamic responses without needing power input, on the contrary extracting power from ambient. This work may open opportunities for thermo-mechano-electrical transduction, multigait soft energy robotics and waste heat harvesting technologies.
The fact that the lifetime of photoluminescence is often difficult to access because of the weakness of the emission signals, seriously limits the possibility to gain local bioimaging information in ...time‐resolved luminescence probing. We aim to provide a solution to this problem by creating a general photophysical strategy based on the use of molecular probes designed for single‐luminophore dual thermally activated delayed fluorescence (TADF). The structural and conformational design makes the dual TADF strong in both diluted solution and in an aggregated state, thereby reducing sensitivity to oxygen quenching and enabling a unique dual‐channel time‐resolved imaging capability. As the two TADF signals show mutual complementarity during probing, a dual‐channel means that lifetime mapping is established to reduce the time‐resolved imaging distortion by 30–40 %. Consequently, the leading intracellular local imaging information is serialized and integrated, which allows comparison to any single time‐resolved signal, and leads to a significant improvement of the probing capacity.
Luminogens for a superior time‐resolved (TR) imaging effect with channel selectivity were achieved by engineering dual thermally activated delayed fluorescence (TADF) from anti‐Kasha/Kasha emission pathways. Intracellular local imaging information that is serialized and integrated was observed by calibrating the two TR signals. The technology is pertinent to precision medicine as TR signals are typically difficult to access in weak emission areas.
Lanthanide metal-organic frameworks (Ln-MOFs) have attracted extensive attention because of their structural adjustability and wide optical function applications. However, MOFs with a wide linear pH ...response and stable framework structures in acidic or alkaline solutions are rare to date. Here, we used 4,4',4″-s-triazine-2,4,6-triyltribenzoate (H
TATB) as an organic ligand, coordinated with lanthanide ions (Eu
/Tb
), and synthesized a new metal-organic framework material. The material has a porous three-dimensional square framework structure and emits bright red or green fluorescence under 365 nm UV light. The carboxyl group of the ligand is prone to protonation in an acidic environment, and negatively charged OH
and ligand (TATB
) have a competitive effect in an alkaline environment, which could affect the coordination ability of ligand. The luminescence degree of the framework decreases with the increase in the degree of acid and base. In particular, such fluorescence changes have a wide linear response (pH = 0-14), which can be used as a potential fluorescence sensing material for pH detection.
In nanoscience, chirality has shown a significant ability to tune materials’ electronic properties, whereas imposing macrochirality into the regulation of singlet–triplet features of organic ...optoelectronics remains a challenging research topic. Since the tuning for singlet and triplet excited-state properties in a single π-functional molecule connects to its multicolor luminescent application and potential improvement of internal quantum efficiency, we here report that supramolecular chirality can be employed to toggle the singlet and triplet emissions in a well-designed asterisk-shaped molecule. Employing a hexathiobenzene-based single luminophore as a prototype and functionalizing it with chiral α-lipoiate side groups, we find that helical nanoarchitectures can accordingly form in mixed DMF/H2O solution. On this basis, switching between fluorescence and phosphorescence of the material can be realized upon helical self-assembly and dissociation. Such a behavior can be attributed to a helical-conformation-dependent manipulation of the intersystem crossing. Furthermore, reversible mechanoluminescence of the corresponding solid sample was also observed to rely on an analogous molecular self-assembly alternation. These results can probably provide new visions for the development of next-generation supramolecular chiral functional materials.
Magnetic control has been a prosperous and powerful contactless approach in arraying materials into high‐order nanostructures. However, it is tremendously difficult to control organic polymers in ...this way on account of the weak magnetic response. The preparation of block copolymers (BCPs) with high magnetostatic energy is reported here, relying on an effective electrostatic coupling between paramagnetic ions and polymer side chains. As a result, the BCPs undergo a magnetically directed self‐assembly to form microphase‐segregated nanostructures with long‐range order. It is emphasized that such a precisely controlled alignment of the BCPs is performed upon a single commercial magnet with low‐intensity field (0.35 Tesla). This strategy is profoundly easy‐to‐handle in contrast to routine electromagnetic methods with high‐intensity field (5–10 Tesla). More significantly, the paramagnetic metal component in the BCP samples can be smartly removed, providing a template effect with a preservation of the directed self‐assembled nanofeatures for patterning follow‐up functionalized species through the original binding site.
By electrostatically coupling quaternized ammonium salt based block copolymers (BCPs) with paramagnetic ions for microphase‐segregated self‐assembly, the BCPs obtain effective magnetic susceptibility. A single neodymium permanent magnet is employed to orientationally direct the self‐assembly of BCPs through the monolith. Microphase domains are packed to form perpendicular or parallel hexagon cylinders along with the magnetic force.
Crystal‐state luminophores have been of great interest in optoelectronics for years, whereas the excited state regulation at the crystal level is still restricted by the lack of control ways. We ...report that the singlet‐triplet emissive property can be profoundly regulated by crystal conformational distortions. Employing fluoro‐substituted tetrakis(arylthio)benzene luminophores as prototype, we found that couples of molecular conformations formed during different crystallizations. The deformable carbon‐sulphur bond essentially drove the distortion of the molecular conformation and varied the stacking mode, together with diverse non‐covalent interactions, leading to the proportional adjustment of the fluorescence and phosphorescence bands. This intrinsic strategy was further applied for solid‐state multicolor emissive conversion and mechanoluminescence, probably offering new insights for design of smart crystal luminescent materials.
Multicolor emission: The deformable carbon‐sulfur (C−S) bond with diverse non‐covalent interactions essentially drives the crystal conformational distortion of asterisk‐shaped luminogen, the fluorescence‐phosphorescence of which can be profoundly regulated by such a crystal multi‐conformational control.
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