Carbon dots have a wide range of applications in biological and medical fields as an alternative to quantum dots because of their low toxicity and excellent luminescence properties. To date, a large ...number of carbon dots have been prepared and they were consequently reviewed according to their synthetic method, luminescence properties and related applications. The dispersibility of carbon dots in aqueous and/or organic solvents could actually play a significant role in the properties and various application fields, however, such a perspective is ignored by most of the reviewed literature studies. Thus in this minireview, we focus on the surfactant groups of carbon dots which could be classified as hydrophilic, hydrophobic and amphiphilic types. They have accordingly a marked impact on the dispersibility of carbon dots in different solvents as well as the further advantage in those imaging studies
in vitro
and
in vivo
.
Carbon dots have a wide range of applications in biological and medical fields as an alternative to quantum dots because of their low toxicity and excellent luminescence properties.
Photothermal materials with broad solar absorption and high conversion efficiency have recently attracted significant interest. They are becoming a fast-growing research focus in the area of ...solar-driven vaporization for clean water production. The parallel development of thermal management strategies through both material and system designs has further improved the overall efficiency of solar vaporization. Collectively, this green solar-driven water vaporization technology has regained attention as a sustainable solution for water scarcity. In this review, we will report the recent progress in solar absorber material design based on various photothermal conversion mechanisms, evaluate the prerequisites in terms of optical, thermal and wetting properties for efficient solar-driven water vaporization, classify the systems based on different photothermal evaporation configurations and discuss other correlated applications in the areas of desalination, water purification and energy generation. This article aims to provide a comprehensive review on the current development in efficient photothermal evaporation, and suggest directions to further enhance its overall efficiency through the judicious choice of materials and system designs, while synchronously capitalizing waste energy to realize concurrent clean water and energy production.
This comprehensive review provides a guide to design photothermal materials and systems for solar-driven water evaporation addressing the water-energy nexus.
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.
Solar energy is a major source of renewable energy with the potential to meet the energy demand and to support the sustainable development of the world. The efficient harvesting and conversion of ...solar energy is one of the key factors to maximize the utilization of solar energy. In general, solar energy can be harnessed and converted into various kinds of energy, including electricity, fuels and thermal energy, through photovoltaic, photochemical and photothermal processes, respectively. Among these technologies, photothermal conversion is a direct conversion process that has attained the highest achievable conversion efficiency. The photothermal effect has been used as a novel strategy to augment vaporization and catalysis performance. In this review, we look into the basis of the photothermal conversion process, the design of efficient photothermal conversion materials in terms of both light harvesting and thermal management, a fundamental understanding of various system schemes, and the recent progress in photothermal evaporation and catalysis applications. This review aims to afford researchers with a better understanding of the photothermal effect and provide a guide for the rational design and development of highly efficient photothermal materials in energy and environmental fields.
Solar-driven photothermal conversion by nanostructured materials is a direct solar energy conversion process that has been used as a novel strategy to augment vaporization and catalysis performance.
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, Volume:
47, Issue:
6
Journal Article
Peer reviewed
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.
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.
Lighting up solid states using a rubber Li, Zhongyu; Wang, Yanjie; Baryshnikov, Gleb ...
Nature communications,
02/2021, Volume:
12, Issue:
1
Journal Article
Peer reviewed
Open access
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.
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.
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