Thermal management has become a critical issue owing to the increasing need for various devices including heat dissipation and adsorption. Recently, the rapid growth of scientific reports is seen to improve thermal management efficiency by developing materials with high transfer coefficient and surface improvement to enhance heat transfer rate. Inspired by nature, constructing superlyophilic interfaces has been proved to be an effective way for thermal management and applied in industry and daily life. Herein, state-of-the-art developments of superlyophilic interfaces assisted thermal management are reported mainly from four perspectives around boiling, evaporation, radiation, and condensation. In particular, we discussed the unique role of superlyophilic interfaces during the heat transfer process, such as increasing bubble detachment rate, superspreading assisted efficient evaporation, directional liquid transfer in textiles during radiative cooling, and so forth. Finally, challenges of thermal management assisted by superlyophilic interfaces toward future applications are presented.
Polymers are widely used in our daily life and industry because of their intrinsic characteristics, such as multi-functionality, low cost, light mass, ease of processability, and excellent chemical stability. Polymers have multiscale space-time properties, which are mainly reflected in the fact that the properties of polymer systems depend not only on chemical structure and molecular properties, but also to a large extent on the aggregation state of molecules, that is, phase structure and condensed state structure. Thanks to the continuous development of simulation methods and the rapid improvement of scientific computation, computer simulation has played an increasingly important role in investigating the structure and properties of polymer systems. Among them, coarse-grained dynamics simulations provide a powerful tool for studying the self-assembly structure and dynamic behavior of polymers, such as glass transition and entanglement dynamics. This review summarizes the coarse-grained models and methods in the dynamic simulations for polymers and their composite systems based on graphics processing unit(GPU) algorithms, and discusses the characteristics, applications, and advantages of different simulation methods. Based on recent studies in our group, the main progress of coarse-grained simulation methods in studying the structure, properties and physical mechanism of polymer materials is reviewed. It is anticipated to provide a reference for further development of coarse-grained simulation methods and software suitable for polymer research.
Selective oxidation of methane to methanol under mild conditions has been considered as a dream reaction but suffers from poor efficiency due to the strong C-H bond of methane and easy overoxidation of the methanol product. For overcoming these problems, a series of strategies has been developed for improving methanol productivity with oxidants of hydrogen peroxide and even a mixture of oxygen and hydrogen at mild temperatures. Significant achievements in these strategies using effective catalysts, such as supported metal nanoparticles, colloidal metal nanoparticles, and metal@zeolites are briefly concluded. Moreover, the current challenges, future perspectives for preparing active, selective, and stable catalysts, have been discussed. The zeolite fixed metal nanoparticle structure has been found to boost the reaction by benefiting the formation and enrichment of peroxide intermediates, which might guide the development of more efficient catalysts.
The carbon composite materials have been a research hotspot in the fields of catalysis, energy conversion and so on, because of their features of large structure and morphology variety, good chemical and electrochemical stability, and high electronic conductivity, large specific surface area and rich active sites. This paper summarizes some research progress of carbon composite materials, including assembly methodologies, their structure regulation, properties, and related applications. Moreover, the current challenges and the prospects of these materials are also discussed.
The development of green and renewable energy sources is in high demand due to energy shortage and productivity development. Artificial photosynthesis(AP) is one of the most effective ways to address the energy shortage and the greenhouse effect by converting solar energy into hydrogen and other carbon-based high value-added products through the understanding of the mechanism, structural analysis, and functional simulation of natural photosynthesis. In this review, the development of AP from natural catalysts to artificial catalysts is described, and the processes of oxygen production, hydrogen production, and carbon fixation are sorted out to understand the properties and correlations of the core functional components in natural photosynthesis, to provide a better rational design and optimization for further development of advanced heterogeneous materials.
Double emulsions have been extensively used in scientific researches and industrial applications due to their attractive unique feature of multiple phases. However, constructing droplets with such a complex structure is not a simple task for all time. The simultaneous existence of two contradictory interfaces makes it hard to prepare stable double emulsions in principle and in practice. Over the past century, tremendous efforts have been devoted by myriads of scientists to make progresses in both theory and preparation of double emulsions. In this review, the current understanding of double emulsions is systematically revealed. In addition to emphasizing the corresponding pioneer and landmark works as many as possible, the state-of-the-art achievements will also be discussed. By regulating the oil-water interface with smartly designed interface-active agents in combination with varying the phase volume fractions, the basic theory framework based on the phase inversion from simple emulsions to double emulsions is also summarized. Technical preparation strategies of emulsification are introduced to show the building process of the two contradictory interfaces in one system. Furthermore, some specific biomedical applications of double emulsions are also discussed, which is expected to stimulate further innovation and utilization of double emulsions.
Volatile organic compounds(VOCs) have become one of the most serious threats to human health and eco-environment due to their volatility, toxicity and diffusivity, etc. Catalytic completely oxidation had been regarded as a highly efficient strategy for the VOCs abatement. Metal or metal oxides supported on zeolite have been considered as superior catalysts for the treatment of VOCs. Among them, Beta zeolites have attracted many attentions due to their unique structure and consequently catalytic properties in the oxidation of VOCs. The progresses and developments made in the understanding and design of Beta zeolites-based catalysts in the completely oxidation of VOCs in the past two decades have been systematically summarized in this review.
Recently, solar-driven synthesis due to its energy-saving and environmentally friendly advantages has attracted more and more attention, whereas the low solar-to-chemical conversion efficiency significantly hindered its development. New effective options that fully utilize full-band sunlight are urgently needed. Novel photothermal catalysis combined with the advantages of photocatalysis and thermalcatalysis can improve the utilization efficiency of solar energy and lower the reaction temperature, thus becoming a promising technology. This review divides photothermal catalysis into photo-assisted thermalcatalysis, thermal-assisted photocatalysis, and photothermal synergistic catalysis. Furthermore, the catalytic mechanical understanding of how photothermal affects the catalytic property of different applications(e.g., water splitting, CO2/N2 reduction, and environmental treatment) was also summed up and discussed in detail. The discussion ends with unsolved challenges in photothermal catalysis, particularly emphasizing the effect of temperature or sunlight on catalytic performance.
Polymer electrolytes have attracted great interest for next-generation lithium-based batteries on account of safety and high energy density. In this review, we assess recent progress on the design of poly(ethylene oxide)(PEO)-based solid polymer electrolytes in high voltage lithium batteries and identify possible side reactions between PEO-based electrolytes and existing cathodes. We provide an overview of the ways to enhance high voltage resistance of PEO-based electrolytes. Those include components blend, molecular design and interface modification. With these efforts, we want to present new insights into rational design of PEO-based electrolytes to develop solid-state lithium batteries for advanced performance.
Two new belt-like borates Na4[B9O14(OH)3]·0.5H2O(1) and Na5[B9O14(OH)4](2) have been synthesized under solvothermal conditions. Both compounds contain unprecedented B9O16(OH) n (n+5)−[n=3(1), 4(2)] clusters, which are constructed from four B3O3 rings via three BO4 tetrahedra. Compound 1 exhibits a rare 1D belt with two types of 8-membered ring(MR) windows based on B9O16(OH)3 8− clusters. Compound 2 features two different 1D belts built by different B9O16(OH)4 9− units, which is first discovered in borate family. UV-Vis diffuse reflectance spectra reveal that compounds 1 and 2 have the cut-off edges below 190 nm, indicating that they may have potential application in deep UV(DUV) region.
Hydrogen is one of the most desirable alternatives to fossil fuels due to its renewability and large energy density. Electrochemical water splitting, as an environmental-friendly way to produce H2 of high-purity, is drawing more and more attention. Conductive nitrogen-doped carbon frameworks derived from metal-organic frameworks(MOFs) have been applied as promising electrocatalysts thanks to their superior conductivity, numerous active sites and hierarchical porous structures. However, traditional uncontrolled pyrolysis will lead to aggregation or fusion of the metal sites in MOFs or even cause collapse of the three-dimensional structures. Herein, we provide a confinement pyrolysis strategy to fabricate a CoCu bimetallic N-doped carbon framework derived from MOFs, which exhibits satisfactory catalytic performance with overpotentials of 199 mV towards hydrogen evolution reaction and 301 mV towards oxygen evolution reaction to reach 10 mA/cm2 in an alkaline solution. This work presents further inspirations for preserving the original skeleton of MOFs during high temperature pyrolysis in order to obtain more stable and efficient electrocatalyst.
Protein structure and protein-protein interactions(PPIs) are crucial for regulating cellular activities required for cell viability and homeostasis. Chemical cross-linking coupled with mass spectrometry(CXMS) has become a versatile tool providing insights into both protein structure with distance restraints and protein-protein interactions with interface sites. Cross-links as the most information-rich data in a CXMS experiment are responsible for the structural model validation and integrative modeling with high throughput and sensitivity. In this work, ensemble refinement of the existing protein structure against the in-vivo cross-linking distance restraints was performed for dynamic protein structure modeling and protein interaction binding interface building in the intracellular environment. These results indicate great potential of in-vivo CXMS data for providing a molecular basis of protein structural dynamics exploration and function performance.
High strength and high toughness are vital for fibers’ engineering applications, but are hard to simultaneously achieve. Herein, we synthesize a carbon nanotube(CNT)-thermoplastic polyurethanes(TPU) fiber reinforced by an amorphous ZrO2 layer through the wet-spinning method. The amorphous ZrO2 layer is in-situ grown on the surface of CNT and the hybrid nanowires are orientedly aligned with TPU to form the ternary fiber. The fiber possesses an excellent combination of high strength(84.6 MPa) and toughness(126.7 MJ/m3), which is outstanding when compared with previously reported CNT-TPU fibers. The pull-out of nanowires attributed to the oriented alignment structure and the enhanced interface and restriction of deformation obtained from the amorphous ZrO2 layer are considered as the primary strengthening and toughening mechanisms. We anticipate that our fiber synthesis strategy gives a new path to design strong and tough fibers.
How water layer adsorbed on solid surface under ambient conditions affects the interfacial friction is a fundamental question for understanding the friction and lubrication phenomena in practical system. We investigate the formation of ice-like(IL) water layers on the hydrophobic surface of graphite with partially covered MoO3 nanoflakes(NFs) using atomic force microscopy(AFM) based techniques. The IL water layers are found surrounding the MoO3 NFs and also intercalated at the MoO3/graphite interface, as proved by thickness measurements as well as local adhesion force and surface potential mappings. AFM manipulations carried out on MoO3 NFs on graphite show that the presence of the IL water layers increases the frictional resistance of the interface. Comparing the results on continuous and discontinuous IL water layers, we can identify the different sliding interfaces in the two scenarios. The increased friction for MoO3 NFs sliding on graphite with an intercalated water layer is attributed to the energy dissipation originated from the metastable nature of the IL layers.
An electrochemical mass spectrometry technique was developed based on a homemade analytical device for sequential analysis of the heavy metals with various speciations in the scales. Four speciations(e.g., water-soluble speciation, organic speciation, indissoluble speciation and elemental speciation) of heavy metals are sequentially extracted by H2O, CH3OH, EDTA-2Na and electrolysis for online electrospray ionization mass spectrometry(ESI-MS) detection. The method takes significant advantages, such as requiring no tedious offline sample pretreatment, high speed of analysis(20 min), high throughput (multi-metals), good sensitivity(0.5 µg/L) and rich chemical information(four speciations). As a result, the rapid comprehensive characterization of four speciations of Pb, Ni, Cu, Zn, Fe, Ba, Mn, Cr and Ca in water pipe scales has been qualitatively achieved. It demonstrated that the present method is a powerful tool for the effective assessment of potential hazards in drinking water, which provides a new analytical idea for evaluating water quality.
Removal of metal ions from water can not only alleviate the scaling problem of domestic and industrial water, but also solve the water safety problem caused by heavy metal ion pollution. Here, we fabricate a positively charged nanofiltration membrane via surfactant-assembly regulated interfacial polymerization(SARIP) of 2-methylpiperazine(MPIP) and trimesoyl chloride(TMC). Due to the existence of methyl substituent, MPIP has lower reactive activity than piperazine(PIP) but stronger affinity to hexane, resulting in a nanofiltration(NF) membrane with an opposite surface charge and a loose polyamide active layer. Interestingly, with the help of sodium dodecyl sulfate(SDS) assembly at the water/hexane, the reactivity between MPIP and TMC was obviously increased and caused in turn the formation of a positively charged polyamide active layer with a smaller pore size, as well as with a narrower pore size distribution. The resulting membrane shows a highly efficient removal of divalent cations from water, of which the rejections of MgCl2, CoCl2 and NiCl2 are higher than 98.8%, 98.0% and 98.0%, respectively, which are better than those of most of other positively charged NF membranes reported in literatures.
A kind of novel environmental-friendly composite absorbent material was designed and prepared in this paper. Nanoscale metal-organic frameworks(MOFs) were embedded in the skeleton of cotton micro fibrillated cellulose. By scanning electron microscope(SEM), we observed that a large number of MOFs were attached to the cellulose skeleton. In addition, under the condition of 1800 r/min vortex, the structure of the composite material was stable and was not easily damaged by external forces. The water contact angle test showed that the composite material had excellent hydrophilicity and could be used for the adsorption of pollutants. Then, the material was characterized by energy dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR) and BET adsorption. Through verification, the material had very stable reusability(n=10). The composite material was applied to the solid phase extraction of water samples, such as rain water, toning water and fruit juice, and was quantitatively analyzed by high performance liquid chromatography(HPLC)-UV. This method was then applied to the extraction of four parabens(methyl-, ethyl-, propyl-, and butylparaben) from real samples, yielding limits of detection(LODs) of 0.29–0.58 ng/mL. The linear range was 2–500 ng/mL. The inter-day and intra-day recoveries were 90.7%–106.0% and 87.1%–109.3%, respectively(relative standard deviation<10.8%).
We report a donor-acceptor(D-A) type non-luminescent neutral radical, tris-2,4,6-trichlorophenylmethyl-N, N-dimethyl-9H-carbazol-3-amine(TTM-Cz-DMA). The results of cyclic voltammetry and quantum chemistry calculation confirm TTM-Cz-DMA has the non-Aufbau electronic structure, which means the singly occupied molecular orbital(SOMO) lies below the highest doubly occupied molecular orbital(HOMO). The non-Aufbau electronic structure changes to the Aufbau electronic structure after protonation and exhibits proton-responsive turn-on fluorescence, which is totally reversible by deprotonation. The dihedral angle between donor and acceptor moieties of TTM-Cz-DMA in excited state reduces from 88° to 62° after protonation, causing the turn-on fluorescence. Our results offer a viewing angle to understand the luminescence of radicals and provide a possible application of proton detection.
Responsive polymers have attracted increasing attention for prospective design of smart materials. The development of multifunctional responsive materials is very dependent on polymeric structures that can be manipulated with the change of microenvironment at the molecular level. Herein, we report a type of responsive coordination polymers(RCPs) consisting of dual phenanthroline-oxadiazole(DPO) units and metal Zn2+ ions, which can contract from linear structure into topologically helical structure driven by hydrophobic effect while changing the microenvironment from nonpolar solvent to aqueous media. The symmetry breaking of RCPs was confirmed by circular dichroism(CD) spectra and atomic force microscope(AFM) images, clearly demonstrating the intramolecularly contraction-arisen helicity. Moreover, RCPs can intelligently adapt different microenvironments by changing their conformations, as evidenced by a demonstration of biomimetic lipid bilayer-based vesicle experiments. Furthermore, RCPs show significant concentration-dependent transmembrane transport functions, implying that RCPs are able to span cellular membranes to form channels inside the hydrophobic lipid bilayers. At the same time, the electrophysiological conductance experiments further underpin the biomimetic transport functions and channel-based conduction mechanism of RCPs. This study demonstrates an important paradigm of responsive polymers performing microenvironment-induced conformational change and thereof unique functions, and thus provides valuable insights on the development of functional responsive materials.
Migraine is an episodic neurological disorder and the second most disabling disease with unclear pathogenesis. Since dietary adjustment and probiotics supplement can improve the symptoms of migraine, the intestinal flora metabolites of bile acids(BAs) attract attentions in this work. 21 BAs, including cholic acid(CA), chenodeoxycholic acid(CDCA), deoxycholic acid (DCA), lithocholic acid(LCA), ursodeoxycholic acid(UDCA), hyocholic acid(HCA), hyodeoxycholic acid(HDCA) and their glycine- and taurine-conjugated species, were compared in serum of migraine patients and healthy controls using liquid chromatography-tandem mass spectrometry(LC-MS/MS), which is the first study about the correlation between BAs and migraine. Two secondary BAs, DCA and LCA as well as their glycine- and taurine-conjugated forms, were demonstrated with significant difference between male patients and male controls, while no obvious difference was found in the two female groups. The result indicated that the variation of BAs might be gender-related when referred to migraine, which would emphasize the importance of gender-stratified analysis for the disease with varying morbidity in male and female. Five differential metabolites may serve as potential serum biomarkers for the male migraine patients, providing a new sight for the understanding and biomarker exploring of the migraine in male.
Electrochemiluminescence(ECL) is a powerful transduction technique used in biosensing and in vitro diagnosis, while the mechanism of ECL generation is complicated and affected by various factors. Herein the effect of ionic strength on ECL generation by the classical tris(2,2′-bipyridyl)ruthenium(II)[Ru(bpy)3 2+]/tri-n-propylamine(TPrA) system was investigated. It is clear that the ECL intensity decreases significantly with the increase of ionic strength, most likely arising from the reduced deprotonation rate of TPrA+·. We further combined microtube electrode(MTE) with ECL microscopy to unravel the evolution of ECL layer with the variation of ionic strength. At a low concentration of Ru(bpy)3 2+, the thickness of ECL layer(TEL) nearly kept unchanged with the ionic strength, indicating the surface-confined ECL generation is dominated by the oxidative-reduction route. While at a high concentration of Ru(bpy)3 2+, ECL generation is dominated by the catalytic route and TEL increases remarkably with the increase of ionic strength, because of the extended diffusion length of Ru(bpy)3 3+ at a reduced concentration of TPrA·.
Molybdenum doping is an effective way to improve the oxygen evolution reaction(OER) properties of catalysts, which can efficiently improve the electronic conductivity, mass transport process, and intrinsic activity of transition metal oxides or hydroxides, especially for those multi-component oxides with more abundant active sites. Herein, we have prepared a quaternary FeCoMoCu metal oxide on Cu foam(FeCoMoCuO x@Cu) as an efficient OER catalyst. As expected, FeCoMoCuO x@Cu could exhibit a low overpotential(252 mV at the current density of 10 mA/cm2) and exceptional stability(10000 cycles of CV scans or constant electrolysis for 48 h).
We present a simple approach to fabricate a kind of composite films with a superhydrophobic and broadband light absorbing surface by ultraviolet-assisted nanoimprinting over a gradiently deposited composite matrix. The wettability and optical property of the resultant surfaces are tunable by the deposition time before polymerization(Ts) and mold’s topography. Mechanically robust and elastomeric films exhibiting high sunlight absorptivity up to 98.13% and contact angle of their surfaces up to 150° are prepared under optimized conditions, as using a mold with a small pattern size(hexagonal periodic mold with cylinder diameter of ca. 37 μm) under Ts =10 min for imprinting the crosslinked poly[di(ethylene glycol) ethyl ether acrylate] and poly(isobornyl acrylate) in the presence of polypyrrole(PPy) nanoparticles. Such dual functions are found related to the hierarchical architecture of the surface, arising from the synergetic effects of the periodical patterned polymer substrate and spontaneously assembled PPy microstructures on the patterns. The current strategy based on the combination of ultraviolet-assisted nanoimprint lithography and hierarchical assembly of gradiently deposited black nano-fillers offers a new insight into the design of robust superhydrophobic and black surfaces, which is helpful to deepen our understanding of the relationship between liquid/light manipulation and micro/nanostructured surfaces.
Environmental pollution is one of the most severe problems facing today, including water pollution and the greenhouse effect. Therefore, developing materials with high-efficiency dyes adsorption and CO2 uptake is significant. Covalent organic frameworks(COFs), as a burgeoning class of crystalline porous polymers, present a promising application potential in areas related to pollution regulation due to their exciting surface properties. Herein, we report a 3D COF with a high specific surface area(BET about 2072 m2/g) by utilizing tetrahedral and rectangle building blocks connected through [4+4] imine condensation reactions to synthesize. The obtained COF not only can separate dyes from water effectively but also shows a remarkable CO2 uptake capacity. This research thus provides a promising material to remove dyes and adsorb CO2 in environmental remediation.
The rabies virus is a neurotropic virus that causes fatal diseases in humans and animals. Although studying the interactions between a single rabies virus and the cell membrane is necessary for understanding the pathogenesis, the internalization dynamic mechanism of single rabies virus in living cells remains largely elusive. Here, we utilized a novel force tracing technique based on atomic force microscopy(AFM) to record the process of single viral entry into host cell. We revealed that the force of the rabies virus internalization distributed at (65±25) pN, and the time was identified by two peaks with spacings of (237.2±59.1) and (790.3±134.4) ms with the corresponding speed of 0.12 and 0.04 µm/s, respectively. Our results provide insight into the effects of viral shape during the endocytosis process. This report will be meaningful for understanding the dynamic mechanism of rabies virus early infection.
We used a diamond anvil cell(DAC) to control the deformation of synthesized copper nanorods and silver nanoparticles. And we measured the surface plasmon resonance of copper nanorods and silver nanoparticles, which exhibit redshifts or blueshifts. The surface plasmon resonance shows an abnormal blue shift for both copper nanorods and silver nanoparticles. The solvents of copper nanorods and silver nanoparticles are n-hexane and water, where the pressure loads include quasi-hydrostatic and non-hydrostatic.