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Bridged carborane–anthracene dyads 1 and 2 exhibit emissions both in solution and in solid state, and blue-shifted mechanochromic luminescence.

High discharged energy density and excellent flexible properties in dielectric materials are significantly sought to meet the rapid advancements in the electronics industry. In this study, covalent bonds are constructed between poly(vinylidene fluoride-chlorotrifluoroethylene), which contains olefinic bonds, and thiol-modified BaTiO3 at the interface before the nanocomposite films are fabricated. The presence of the covalent bonds is proved to promote the dispersibility of the modified BaTiO3 and enhance the interfacial adhesion between the modified BaTiO3 and the polymer, followed by a remarkably positive effect in suppressing the dielectric loss (tanδ) and increasing the breakdown strength (Eb) of the nanocomposite films. In addition, the cross-linking treatment in the preparation process is found to be favourable for improving the mechanical properties of the nanocomposite films, which benefits the enhancement of Eb. Furthermore, at 400% elongation, the stretched nanocomposite film doped with 5 vol% modified BaTiO3 exhibits an Eb 15.6% greater than that of the unstretched film, and the discharged energy density reaches 11.4 J/cm3 with a high discharge energy efficiency of 84.5%. This study provides a novel strategy for preparing flexible nanocomposites with powerful interfacial adhesion at high filler content to achieve high discharged energy density.

A magic cube-like NH2-Ce-BDC is prepared, and its derived CeO2 has demonstrated to be a good support for ALD-prepared Pt for catalyzing HCHO oxidation.

The luminescence properties of three fluorinated tetraphenylethene (TPE) derivatives indicate that the fluorine atom has a significant effect on the solid state packing, and thus the emissions and the stimuli-responsiveness.

Novel phosphate-crosslinked β-cyclodextrin polymer was synthesized for highly efficient Pb(ii) removal from acidic wastewater.

Novel superhydrophilic polystyrene phosphate resin was synthesized for efficient and rapid Pb(ii) removal from acidic wastewater.

α-Al2O3 nanoparticles are easy to agglomerate in the preparation, thereby leading to adverse effects during the applications. This paper reported the preparation of α-Al2O3 nanoparticles with good dispersity and controllable morphology by lowering temperature calcination of the precipitated precursor powders. The composite composed of PVP and ammonium sulfate is used to control the morphology and improve the precursor's dispersion. The influences of R ((NH4)2CO3/Al3+, molar ratio) and PVP-ammonium sulfate composite were studied thoroughly. It was found that an urchin-shaped ammonium aluminum carbonate hydroxide (AACH) precursor can be formed under the conditions of R = 3, and the ammonium sulfate and PVP are 20 wt% and 5 wt%, respectively. After calcination at 1000 °C for 2 h, such urchin-like precursor particles were converted to quasi-spherical and well crystallized α-Al2O3 nanoparticles, which possessed a narrow size distribution of 110 nm and a specific surface area of 12.13 m2/g. The resultant α-Al2O3 nanoparticles prepared by such a simple method were expected to be applied in transparent ceramics and high-performance catalysts.

Due to the effects of climate changing, the importance of outdoor thermal comfort has been recognized, and has gained more and more research attentions. Unlike indoor space where air conditioning can be easily implemented, outdoor thermal comfort can only be achieved by localized thermal management. Using textile is a simple but energy-saving way to realize outdoor thermal comfort. Herein, we report the design of a smart thermal management film with the silver/vanadium dioxide/silver (Ag/VO2/Ag) sandwich structure prepared by one-dimensional (1 D) nanowires. It was found that the Ag/VO2/Ag sandwich film was able to lower the temperature by around 10 °C under intense infrared (IR) radiation. In addition, the Ag/VO2/Ag sandwich structure film showed a thermo-responsive electrical conductivity and an outstanding bending stability, due to network structure formed by nanowires. It was experimentally proved that this sandwich structure was superior to other layer structures in IR shielding performance and thermo-responsive electrical conductivity. The as-prepared Ag/VO2/Ag sandwich structure film has great potential for various applications such as wearable devices, flexible electronics, medical monitors and smart IR radiation management.

Removing heavy metal ions from acidic mine wastewater is a big challenge. In this paper, a novel porous thiophosphoryl polyethyleneimine (TPEI) adsorbent was designed for removing Pb(II) and Cr(VI) from acidic wastewater. The optimum adsorption pH value of TPEI for Pb(II) and Cr(VI) is 3 and 2, respectively. At 298 K, the maximum adsorption capacity for Pb(II) and Cr(VI) is 421.9 mg g−1 and 191.04 mg g−1, respectively. The adsorption equilibrium time of Pb(II) and Cr(VI) is 25 min and 10 min, respectively. The adsorption of Pb(II) and Cr(VI) both conform to the pseudo-second-order model and the Langmuir isotherm model. The adsorption mechanism of Pb(II) depends on the chelation interaction, while Cr(VI) depends on the electrostatic interaction. The regeneration test shows that the adsorbent is stable and reusable. This study provides a new strategy for the purification of acidic heavy metal wastewater.

Hydrogen (H2) has been considered as one of the cleanest renewable energy sources. However, it is still challenging to use H2 due to its hazardous flammable and explosive properties under mild conditions in the event of leakage, and the difficulty to detect or sense it through human sensory organs because of its colorless and odorless nature. Traditional detection methods are usually complicated and the testing instruments are expensive. Thus, it is of significant importance to develop sensors for H2 detection with facile operation conditions, low costs, and excellent performance (i.e., sensitivity, selectivity, and stability). To overcome the problems and for practically detecting H2 gas, metal oxide (MOx) nanomaterials have become more crucial in such a gas sensor because of the simple preparation method, high surface area, high sensitivity, and low costs. This review will focus on the recent state-of-the-art advances in resistive H2 gas sensors based on MOx nanomaterials, starting from a brief introduction of resistive gas sensors. The following sections will focus on the synthesis of different structures and types of such MOx nanomaterials, including mono/binary/ternary/ternary or more complicated MOx nanomaterials. Meanwhile, we highlight some regulation methods such as surface or inner decoration by noble or non-noble metals to improve the performance as well as summarize and compare different structures (core–shell and heterojunction), and mechanisms in H2 sensing. Finally, the opportunities and challenges of MOx-based H2 gas sensors are proposed in detail.

Simultaneously maximizing the dispersion of noble metals and demonstrating optimal activity are of significant importance for designing stable metal catalysts. In this study, highly dispersed ultrafine platinum (Pt) particles with a size of

Density function theory (DFT) method was developed and applied for fundamentally understanding the doping effect of various metals (Al, Ti and Cr) on vanadium dioxide (VO2). The substitution doping of Al, Ti and Cr in VO2 could lead to significant changes in electronic structure, band gap and optical property. Different from physical experiments, the DFT method could be utilized for fundamental understandings at an atomic scale. It was found via DFT calculations that: (i) Al doping caused a slightly distorted octahedron in monoclinic VO2(M), and narrowed the band gap of VO2(M) due to the upward shift of the valence band (VB), while Cr doping narrowed the band gap because of the downward shift of the conduction band (CB); (ii) Ti doping slightly widened the band gap of VO2(M); and (iii) the optical reflectivity of VO2(M) decreased after substitution doping low-valent metals (e.g., Al). This study will be beneficial for designing and controlling elemental doping to obtain metal oxide nanocomposites with unique band gap and electronic structure for thermochromic energy saving applications.

This study represents a facile but efficient glycothermal method for synthesis of vanadium dioxide, VO2(B) nanoparticles with various geometries from spheres to rods, flakes or their agglomeration structures, by controlling reaction conditions (e.g., vanadium resources, reducing agents and surfactants). The as-prepared VO2(B) nanoparticles were characterized in microstructure and composition, and also examined in terms of gas sensing performance. It was found that the VO2(B) nanoparticles exhibit a good sensitivity towards alcohols (ethanol, isopropanol, and butanol) and acetone at the optimised operating temperature of 300 °C. The gas sensing performance was further compared with other vanadium oxides investigated previously, such as V2O5, Na1.08V3O8. The plausible gas sensing mechanism of the as-prepared nanoparticles was discussed in detail. This study would expand the family of vanadium oxides that can be made as potential sensors for applications in detecting environmental safety and human health.

This study demonstrates the tailorable self-weaving of bimetallic nickel–cobalt (Ni–Co) hydrogen phosphate nanotubes into one-dimensional (1D) microspindles or two-dimensional (2D) sheet-like structures by utilizing monodispersed Ni–Co glycerate spheres as sacrificial templates. The conversion process is achieved through a two-step solvothermal method in the presence of phosphoric acid (H3PO4) as a phosphorus source and promoter of the self-weaving process. The formation of such nanotube-assembled architectures is promoted by the “peeling-self-weaving” mechanism, in which the bimetallic Ni–Co hydrogen phosphate nanotubes initially grow on the surface of the Ni–Co glycerate spheres due to the reactions between Ni and Co metals bonded to the glycerate anions with hydrogen phosphate anions present in the solution. This is followed by the peeling of the overgrown nanotubes from the etched glycerate spheres and their self-weaving into 1D or 2D architectures depending on the Ni/Co molar ratio. The electrocatalytic test results reveal the superior activity of the Ni-rich Ni–Co hydrogen phosphate electrode for oxygen evolution reaction (OER) compared to its Co-rich and equimolar counterparts, leading to smaller overpotential of 320 mV and lower Tafel slope of 84 mV dec−1. Post-OER analysis of this sample reveals that the high OER activity is derived from the formation of active Ni–Co oxyhydroxide phase on its surface.

Highly efficient and stimuli-responsive luminescent materials are desirable candidates in various applications. In this work a bis(naphthyl)phenyl-substituted o-carborane (1) was synthesized by a Suzuki cross-coupling reaction. The X-ray crystal structure analysis indicates multiple weak interactions (intermolecular C-H⋯π, intramolecular C-H⋯H-B, and intermolecular B-H⋯π hydrogen bonding interactions) are present which may explain the high solid state emission efficiency (0.99). Compound 1 exhibits multiple fluorochromism towards mechanical force, solvent vapor and temperature, which holds promise for further application studies. The emission mechanism is mainly the intramolecular charge transfer induced by the electron-withdrawing carborane as supported by the TD-DFT calculations.

Recent advances in the clothing for thermal management have opened up prospects for exploration of its fundamental physical properties and practical applications to humans. Heat transfer between human skin and environment is mainly dependent on the synergetic effect of environment temperature, atmosphere motion, mean radiant temperature, relative humidity and the clothing. New materials and structures should be exploited to fabricate advanced textiles and clothing having light weight and flexibility as well as excellent thermal management. This article aims to review recent progress in the development of thermal management textiles, focusing on strategies that use advanced materials to control the heat transfer between the human body and the environment. This review details three mechanisms for managing heat transfer. According to these mechanisms, three main strategies based on novel materials and structures will be demonstrated in detail. In addition, thermal management clothing with supplied power is also discussed. Advantages and drawbacks of different types of clothing will be discussed. Moreover, different systems and devices for evaluating the performance of thermal management textiles are summarized. Finally, some perspectives on thermal management clothing are provided for future research.

This study demonstrates a novel one-dimensional core-shell structure based on the coating of silver nanowires (Ag NWs) with a layer of titanium oxide (TiO2) nanoparticles. This approach for generating core-shell structures is facile and straightforward, utilizing a sol-gel method followed by the crystallization of TiO2 using a simple open-air hydrothermal method. The Ag nanowires are ˜10 μm in length and have a diameter of 100 nm, and their TiO2 polycrystalline shell is 10–15 nm in thickness. These novel structures offer large surface area and high stability, which are qualities that favor gas sensing performance. Gas sensing tests have demonstrated that the generated Ag NWs@TiO2 core-shell nanocomposites exhibit better sensing properties (response, selectivity, optimized working temperature, minimum concentration, and response and recovery time) when compared to sensors containing pure TiO2 nanoparticles. The mechanism of sensing enhancement can be attributed to the Schottky barrier that exists at the interface between the Ag NWs and the TiO2. The Ag core has an excellent conductive property for electronic transfer and further accelerates the oxygen ionization and surface redox reactions. These results may shed light on the design and construction of TiO2-based nanocomposites for gas sensor applications.

Utilizing fewer functional materials to achieve multifunctional fabrics via facile approaches have been confronting worldwide scientists with an enormous challenge. In this study, a novel multifunctional cotton fabric, combining UV/NIR shielding and full-spectrum-responsive self-cleaning, has been fabricated via self-assembly of CsxWO3 nanosheets based on electrostatic interaction assisted by Poly (diallyldimethylammonium chloride) (PDDA) in aqueous solution. The microstructure of CsxWO3 nanosheets and their self-assembly coating on cotton fabric were characterized and investigated. The functional properties of the CsxWO3-coated cotton fabric, including UV/NIR shielding and photocatalytic self-cleaning were evaluated. The results indicate that the CsxWO3-coated cotton fabric exhibits superb UV/NIR and heat shielding performance with 15.8 °C and 5.9 °C lower than no coverage and coverage by none-treated cotton fabric, respectively. Moreover, the well-coated cotton fabric demonstrates photocatalytic self-cleaning property responsive to the light ranging from UV, Vis to NIR, especially exhibits highly efficient self-cleaning under the respective irritation of full-spectrum, UV and Vis light (color faded completely within 10 h). In summary, the CsxWO3-coated fabrics can achieve multi-functions of UV shielding, heat insulation and self-cleaning by means of a single functional nanomaterial and promise of huge applications in functional textiles.

This work reports the fabrication of a three-dimensional (3D) zinc oxide/zinc cobaltite (ZnO/ZnCo2O4) hybrid with a hierarchical macroporous honeycomb-like structure using highly uniform cobalt glycerate spheres as a self-sacrificial template. In the proposed method, the conversion of the template cobalt glycerate nanospheres into a 3D hierarchical macroporous honeycomb-like ZnO/ZnCo2O4 hybrid is achieved via a facile room-temperature reaction with aqueous zinc nitrate solution, followed by calcination in air at 350 °C. The proposed method offers several benefits including (i) the attainment of the ZnO/ZnCo2O4 hybrid in one step without additional or separate coating steps, (ii) the achievement of a unique 3D hierarchical macroporous honeycomb-like structure with interconnecting nanosheets and macropores which are assembled from smaller mesopores, leading to higher surface area and good interparticle separation, (iii) the relatively low calcination temperature required to obtain the ZnO/ZnCo2O4 hybrid (350 °C) and (iv) potential generalization for the creation of other macroporous honeycomb-like cobalt-based oxide nanostructures (including Al–Co and Cu–Co systems). When evaluated as a sensing material for carbon monoxide (CO), the hierarchical honeycomb-like ZnO/ZnCo2O4 hybrid sensor displays a higher sensing response with enhanced selectivity and stability towards CO gas at 300 °C compared to both ZnO hierarchical spheres and ZnCo2O4 nanospheres. The enhanced sensing performance of the hierarchical honeycomb-like ZnO/ZnCo2O4 hybrid is derived from the synergistic cooperation of the formed p–n heterojunction, large surface area and hierarchical macroporous nature of the as-synthesized ZnO/ZnCo2O4 hybrid. It is expected that the proposed general method may open a new path for creating other hierarchical macroporous honeycomb-like oxide nanostructures with enhanced surface areas and improved functional performance.

Fluorine and tin co-doped rutile TiO2 nanorod arrays are grown on fluorine-doped tin oxide substrates by a hydrothermal process and are used as photoanodes to perform photoelectrochemical water oxidation. Fluorine and tin co-doping synergistically enhances the ultraviolet light conversion efficiency of the resulting TiO2, which enables its photocurrent density of photoelectrochemical water oxidation to be more than four times that of the undoped samples. Such improvement in photoelectrochemical performance is attributed to changes in the electronic structure of the rutile TiO2 due to fluorine and tin co-doping. It is found that introducing tin into the matrix of rutile TiO2 can improve the charge separation efficiency because of the enhanced migration of photogenerated electrons from the conduction band of TiO2 to that of SnO2 that occurs at local sites, while fluorine doping can greatly reduce the recombination of the photogenerated electron–hole pairs due to the presence of the Ti3+ state that is produced to compensate for the charge difference between F− ions and O2− ions. It is envisaged that the fluorine and tin co-doped TiO2 nanorod arrays described will provide valuable platforms for wide photocatalytic applications that are not merely limited to photoelectrochemical water oxidation.

The Suzuki–Miyaura cross-coupling reactions of bromoalkenes with fluorophenylboronic acids afforded 17 fluorinated tetraphenylethene (FTPE) compounds that have only fluorine substituent(s) directly on the tetraphenylethene (TPE) core with different numbers and substitution positions of the fluorine atom(s). The X-ray structures of four FTPEs show that these FTPE derivatives have C–H⋯F and C–H⋯π hydrogen bonds in the crystal packing. DFT calculations indicate that both the HOMOs and LUMOs of the FTPEs essentially have lower energy levels than those of the parent TPE, and the energy gaps are highly dependent on the substitution pattern. These FTPEs exhibit aggregation-induced emission characteristics similar to most TPE derivatives but the aggregation process was found to be gradual and time-dependent. The emission wavelengths of both aggregates from tetrahydrofuran/H2O and solids, and the corresponding emission quantum yields of the solid samples vary with different substitution patterns. In addition, two examples of these FTPEs show reversible mechanofluorochromic and thermofluorochromic properties (the latter was only shown on silica gel), while the parent TPE does not exhibit mechanochromism under the same conditions.

This study represents a facile but effective room-temperature strategy for the synthesis of shape/size-controlled cuprous oxide (Cu 2 O) nanoparticles under mild conditions. The proposed synthesis method offers several advantages/novelties including: room-temperature processing, simple operation procedures, controllable shape and size, high yield, and available for scaling up. The effects of the pertinent variables on the particle formation and growth have been investigated, such as concentration of copper ions (Cu 2+ ), surfactants, reducing agents, and the molar ratios among variables. The composition, microstructure and optical properties were then characterized using advanced techniques. It was found that the use of different surfactants may result in significant morphology changes from spheres to octahedrons and/or wires under the reported conditions. To enhance photocatalytic performance in dye degradation, the Cu 2 O nanoparticles could be further surface decorated by titanium dioxide (TiO 2 ) to form heterogeneous nanocomposites that can improve the electron-hole separation. This study may be useful to develop simple but general approaches to obtain cuprous/copper oxides and other hybrid semiconductor nanostructures with structure and functional control for catalysis and sensing applications.

The multifunction antibacterial hemostatic materials can reduce blood loss, infection and wound complications, which probably decrease morbidity and health care costs. However, the contradictory relationship between antibacterial ability and biocompatibility, and the unnecessary blood loss restricts the practical application of hydrophilic cationic antibacterial hemostatic materials. Herein, a multifunctional temperature-triggered antibacterial hemostatic fluorocopolymer aggregate coating was developed. After self-assembly and quaternization process, the quaternized poly(N,N-dimethylaminoethylmethacrylate)-b-poly(1H,1H,2H,2H-heptadecafluorodecyl acrylate) block copolymers (PDMA-b-PFOEMA) aggregate coating consisting of fluoropolymer and quaternary ammonium salt were built. The synergistic effect on fluorinated block with low surface energy and quaternary ammonium salt block with bactericide activity severs the way of initial bacterial attachment and proliferation, while the migration of fluorinated block greatly promotes the biocompatibility and anti-adhesion performance in response to the switch from room temperature to physiological temperature. Furthermore, the fluorocopolymer aggregate coating with hydrophobic properties possessed the property of rapid coagulation, low blood loss, minor secondary bleeding and least bacteria infiltration. The multifunctional temperature-triggered fluorocopolymer aggregate coating with antifouling, antibacterial and hemostatic properties may have a great potential in the biomedical application.

Vanadium dioxide (VO2) has demonstrated highly potential for smart windows because of its thermochromic property. This study represents the development of a facile but efficient method for the synthesis of VO2 (M) nanoparticles by ball milling method under ambient conditions, without release of waste liquid or gases. The key variables related to synthesis, including milling time and molar ratio of raw materials, have been investigated. It was found that the pure-phase VO2 (M) nanoparticles with the sizes of the particles ranged from 20 to 50 nm and relatively good dispersivity could be prepared by optimizing process parameters. For practice use to decrease the phase transition temperature, elemental W doping amount of 2 at.%, V1−xWxO2 (M) nanoparticles were also studied, and their glass coating exhibits high thermochromic performance with luminous transmittance (Tlum) of 44.18%, solar regulation efficiency (∆Tsol) of 9.64%, and the critical phase transition temperature (Tc) of ~ 42 °C. This work demonstrates a green and promising ball milling method to fabricate large scale VO2 (M) and V1−xWxO2 (M) nanoparticles for smart windows.