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The complex micromechanical response among grains remains a persistent challenge to understand the deformation mechanism of titanium alloys during cold rolling. Therefore, in this work, a multiscale crystal plasticity finite element method of dual-phase alloy was proposed and secondarily developed based on LS-DYNA software. Afterward, the texture evolution and slip mode of a Ti-5.5Mo-7.2Al-4.5Zr-2.6Sn-2.1Cr alloy, based on the realistic 3D microstructure, during cold rolling (20% thickness reduction) were systematically investigated. The relative activity of the 2 ¯ 0>{0001} slip system in the α phase gradually increased, and then served as the main slip mode at lower Schmid factor ( 2 ¯ 3>{10 1 ¯ 1} slip system to the overall plastic deformation was relatively limited. For the β phase, the relative activity of the {110} slip system showed an upward tendency, indicating the important role of the critical resolved shear stress relationship in the relative activity evolutions. Furthermore, the abnormally high strain of very few β grains was found, which was attributed to their severe rotations compelled by the neighboring pre-deformed α grains. The calculated pole figures, rotation axes, and compelled rotation behavior exhibited good agreement to the experimental results.

The wetting of 3% yttria-stabilized zirconia (YSZ) by Sn–8Zr, Sn–4Zr–4Ti, and Sn–8Ti alloys was studied at 800–900 °C. Both Zr and Ti improve the wettability via the formation of reaction products and adsorption. In the systems containing Zr additives in the alloys, ZrO2-x precipitates preferentially, and the wettability is dominated by interface adsorption. An anomalous temperature dependence was found in the final wettability of these systems owing to the decrease in adsorption with an increase in the temperature. The spreading dynamics are controlled by the dissolution of Zr, followed by the formation of a wetting ridge. The wettability of the Sn–8Ti/YSZ system is dominated by the precipitation of reaction products (Ti2O3 and Ti11.31Sn3O10). The reaction kinetics is the limiting factor for spreading in Sn–8Ti/YSZ, and the adsorption at the interface significantly decreased the energy barrier for wetting.

In the current study, we fabricated a cardiac patch composed of gold nanowires incorporated in collagen fibres by electrospinning followed by chemical crosslinking. Two other counterparts of the cardiac patch were fabricated; one with gold nanowires incorporated in collagen fibres without chemical cross linking and other with only collagen fibres. The surface morphology of the cardiac patch was viewed via microscopy images and a complete analysis of the mechanical strength of the cardiac patch was done. Swelling and suture resistance tests along with cytotoxicity investigations were performed. Cell adhesion and proliferation were observed on the cardiac patch by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and scanning electron microscope with impediametric studies. This cardiac patch had enhanced mechanical properties and increased hydrophilicity. The cardiomyocytes when seeded this cardiac patch exhibited good cell preservation, growth and sustainability. A layer of cells formed over the cardiac patch was seen by microscopic images because of better cell sustainability. It was observed that in cardiac patch with only porous matrix of collagen fibres, the mechanical strength, suture resistance and cell proliferation were less than when embedded with gold nanowires. Hence, this study clearly exhibited a bioengineered cardiac patch with improved efficacy for management of cardiac infarction.

Whether the rough surface is beneficial or harmful in promoting wettability for a reactive wetting system at high temperatures remains an open question. The comparative study on the wetting of smooth and rough silica by Sn-3.5Ag–2Ti solders were carried out at 650–800 °C. Although the precipitation of wettable reaction products promotes wettability, the decrease in interfacial roughness by the precipitates makes the improvement in wettability does not reach the degree of inert system. Therefore, the rough surface is harmful in promoting wettability for a reactive wetting system. The wetting behavior can be divided into two types by temperatures: the linear spreading (650–700 °C) and the non-linear spreading (750–800 °C) which correspond to the reaction rate control mechanism and the diffusion control of Ti transport mechanism, respectively. The spreading is enhanced by using the rough substrate due to the strengthening interfacial reactivity.

Rare earth nickelates including LaNiO3 are promising catalysts for water electrolysis to produce oxygen gas. Recent studies report that Fe substitution for Ni can significantly enhance the oxygen evolution reaction (OER) activity of LaNiO3. However, the role of Fe in increasing the activity remains ambiguous, with potential origins that are both structural and electronic in nature. On the basis of a series of epitaxial LaNi1-xFexO3 thin films synthesized by molecular beam epitaxy, we report that Fe substitution tunes the Ni oxidation state in LaNi1-xFexO3 and a volcano-like OER trend is observed, with x = 0.375 being the most active. Spectroscopy and ab initio modeling reveal that high-valent Fe3+δ cationic species strongly increase the transition-metal (TM) 3d bandwidth via Ni-O-Fe bridges and enhance TM 3d-O 2p hybridization, boosting the OER activity. These studies deepen our understanding of structural and electronic contributions that give rise to enhanced OER activity in perovskite oxides.

The research on van der Waals (vdW) layered ferromagnets have promoted the development of nanoscale spintronics and applications. However, low-temperature ferromagnetic properties of these materials greatly hinder their applications. Here, we report pressure-enhanced ferromagnetic behaviours in layered CrSiTe3 flakes revealed by high-pressure magnetic circular dichroism (MCD) measurement. At ambient pressure, CrSiTe3 undergoes a paramagnetic-to-ferromagnetic phase transition at 32.8 K, with a negligible hysteresis loop, indicating a soft ferromagnetic behaviour. Under 4.6 GPa pressure, the soft ferromagnet changes into hard one, signalled by a rectangular hysteretic loop with remnant magnetization at zero field. Interestingly, with further increasing pressure, the coercive field (H_c) dramatically increases from 0.02 T at 4.6 GPa to 0.17 T at 7.8 GPa, and the Curie temperature (T_c^h: the temperature for closing the hysteresis loop) also increases from ~36 K at 4.6 GPa to ~138 K at 7.8 GPa. The influences of pressure on exchange interactions are further investigated by density functional theory calculations, which reveal that the in-plane nearest-neighbor exchange interaction and magneto-crystalline anisotropy increase simultaneously as pressure increases, leading to increased H_c and T_c^h in experiments. The effective interaction between magnetic couplings and external pressure offers new opportunities for both searching room-temperature layered ferromagnets and designing pressure-sensitive magnetic functional devices.

Concrete structures often undergo both fatigue loading and environmental impacts during their useful lifetime. This study aims to explore the fatigue properties of concrete subjected to sulfate attacks under drying–wetting cycles and loading. The coupled influences of major cycle number and sodium sulfate solution on the residual deformation, elastic modulus, and damage variable were investigated by uniaxial cyclic loading tests. Moreover, the phase composition of concrete samples was examined by X-ray diffraction. Results indicate that the concrete residual deformation and damage variable could be classified into initial and stable stages, while the elastic modulus fluctuated within a certain range. The fatigue strength of concrete was found to increase with an increase in the major cycle number and sodium sulfate concentration in the early stages, whereas the fatigue performance of concrete decreased as the major cycle number and sodium sulfate concentration increased in the later stage. The degree of influence of major cycle number and sodium sulfate concentration on the fatigue properties of concrete differed in each stage. These findings can contribute to understand the variation pattern of concrete properties in complicated environments and provide an important reference for associated construction projects.

The optical plasmonic cavity (OPC) including the metallic optical nanoantennas and a metal film exhibits extreme field enhancement for the increased spontaneous emission rate of emitters. The resonance wavelength of the OPC can be easily controlled by the volume of the OPC and the localized surface plasmonic resonances (LSPRs) of the nanoantennas, facilitating the effective coupling of OPC and the emitters. However, involving the OPC into the light emission-enhanced solution-processed devices is still a difficult challenge. The trade-off between the metallic structure of OPC and the solution procedures limits the performance enhancement of the electrical-driven devices. In this work, we construct a device-compatible OPC that allows the characterization of the carrier dynamics of quantum dot (QD) films in the real devices in-suit. The radiative recombination rate and relaxation rate of carriers in QDs are increased by the LSPR effect of the silver nanocubes for luminescence enhancement. The OPC further increases the spontaneous emission rate of QD films, achieving a Purcell factor of 166 and improving the electroluminescence of the OPC-based QD light-emitting diodes (QLEDs). The design of the OPC-involved QLEDs offers a solution for addressing the limitation of fabrication of OPC-combined solution-processed optoelectronic light sources.

The heating method of SCWG reactor is critical to system construction, and almost all existing reactors rely on external heat sources. In this article, the thermodynamic equilibrium model is established to predict the distribution of gasification products from supercritical water gasification of coal. The transformation rule of gas components in the SCWG process of coal and oxidation process of gasification products is explored. Especially, the influence of key parameters such as feedstock concentration, gasification temperature and pressure on the hydrogen yield during the gasification and oxidation processes is also discussed. Based on the above research, the autothermal gasification system for hydrogen production integrated supercritical water gasification of coal and oxidation of gasification products is proposed. The flow matching of supercritical water, coal slurry, and oxygen and its effect on the autothermal hydrogen yield are discussed. By optimizing the flow rate of the reactants, 80% of the hydrogen production efficiency is achieved.

Using CaO, Y2O3, Al2O3, and SiO2 micron-powders as raw materials, CaO–Y2O3–Al2O3–SiO2 (CYAS) glass was prepared using water cooling method. The coefficient of thermal expansion (CTE) of CYAS glass was found to be 4.3 × 10−6/K, which was similar to that of SiCf/SiC composites. The glass transition temperature of CYAS glass was determined to be 723.1 °C. With the increase of temperature, CYAS glass powder exhibited crystallization and sintering behaviors. Below 1300 °C, yttrium disilicate, mullite and cristobalite crystals gradually precipitated out. However, above 1300 °C, the crystals started diminishing, eventually disappearing after heat treatment at 1400 °C. CYAS glass powder was used to join SiCf/SiC composites. The results showed that the joint gradually densified as brazing temperature increased, while the phase in the interlayer was consistent with that of glass powder heated at the same temperature. The holding time had little effect on phase composition of the joint, while longer holding time was more beneficial to the elimination of residual bubbles in the interlayer and promoted the infiltration of glass solder into SiCf/SiC composites. The joint brazed at 1400 °C/30 min was dense and defect-free with the highest shear strength of about 57.1 MPa.

Ag/ZnO hybrid cages with well-preserved polyhedron shape and rich mesoporous structures were prepared thorough in situ pyrolysis of AgNO3 impregnated ZIF-8 precursor. Due to the bi-template function of ZIF-8, the as-prepared cages show well-defined hollow chamber inherited from the precursor and uniformly embedded Ag nanoparticles (NPs). The as-introduced Ag NPs could enhance the light absorption and promote charge separation, which finally improve the antibacterial performances. Therefore, compared with pure ZnO, the Ag/ZnO hybrid cages demonstrate prominent photocatalytic degradation of different organic dyes, such as Methylene Blue, Methylene Orange, Eosin and Rhodamine B under simulated sunlight. In addition, the hybrid Ag/ZnO cages exhibit outstanding inhibition performances against Escherichia coli, Staphylococcus aureus, and the highly infective Mycobacterium-tuberculosis. The photocatalytic and antibacterial mechanism of the hybrid Ag/ZnO cages were also studied in detail by means of optical/electrochemical dynamic tests and Ag+ and Zn2+ release measurements.

A combination method of precursor infiltration and pyrolysis (PIP), chemical vapor infiltration (CVI) and liquid silicon infiltration (LSI) was proposed to prepare PIP-SiC modified C/C–SiC brake materials. The SiC ceramic matrix pyrolyzed by polymethysilane (PMS) homogeneously dispersed in the fiber bundles region, which improved the plough resistance of local C/C region and the wear resistance of C/C–SiC brake materials. When the braking speed rises to 28 m/s, the fluctuation range of friction coefficient was limited to 0.026. The linear wear rate of the as-prepared composites was could be ~50% less than that of C/C–SiC, when the braking speed was above 15 m/s (for instance, the wear rate of 1.02 μm/(side·cycle) at 28 m/s less than 2.02 μm/(side·cycle) of traditional C/C– SiC). The fading ratio D of CoF under wet conditions was ~11%. The results showed that introducing PIP-SiC could stabilize the braking process and effectively prolong the service life of C/C–SiC brake materials.

MAA (mesh aluminium alloy) is one of the most widely used explosion suppression materials in military and civilian applications. To systematically research the effect of MAA on the explosion reactions of flammable gases, we investigated the effect of MAA and AV (aluminium velvet) on the explosion of hydrogen-air, methane-air and acetylene-air mixtures. The results indicated that MAA and AV suppress the methane-air mixture explosion but significantly promote the explosions of the hydrogen-air mixture and the acetylene-air mixture. MAA and AV have the dual effect of promoting and suppressing an explosion. In addition, with an increase in filling density, the promotion of MAA and AV first strengthens and then weakens. The results of this study show that the properties of flammable gas, not the shapes of the explosion suppression materials, determine whether the dominant effect of explosion suppression material is promotion or suppression. Use of explosion suppression materials is not suitable for all flammable gases, especially highly reactive chemical fuels. Applying explosion suppression materials blindly may greatly increase safety risk.

Organic polymers have been found widespread commercial applications due to their easy processing and attractive mechanical properties. Concurrently, inorganic polyoxometalates (POMs), a class of metal-oxygen anionic and nanosized clusters of early transition metals, have a wide range of attractive functions and are used in industrial catalysis. In this communication, we report a new approach to creating the first linear poly(polyoxometalate)s that combine the advantages of polymers and POM clusters. In the experiment, a POM-containing norbornene monomer was first synthesized by linking a Wells-Dawson-type POM with a norbornene derivative. The monomer was polymerized in the presence of a Grubbs catalyst under mild conditions with yields nearly 100% in a living and controllable manner. The resulting poly(polyoxometalate)s have controllable molecular weights and a well-defined hybrid structure of an organic polynorbornene backbone with large pendant groups of the nanosized POM clusters. Thus, they form good films and have a good catalytic performance. Our findings not only pave the way for incorporating the POM clusters into polymers with well-defined structures and high molecular weights, but also offer a competitive strategy for developing more novel catalytic systems by introducing the poly(polyoxometalate)s.

A series of experiments were conducted to investigate the wettability of graphite plate, graphite paper, NWCNTs Buckypaper, CVD-diamond by molten Ce and graphite plate by Cu–Ce binary alloy using a modified sessile drop method at 950 °C. The remarkable apparent equilibrium contact angles (graphite plate (0°)

Lamination technique is one of the most promising and effective approaches to produce flexible organic solar cells (OSCs), with the combination of high throughput and simultaneous encapsulation. In this study, flexible ITO‐free OSCs were successfully fabricated by lamination technique under the optimized temperature and pressure. It is found that the introduction of hole interface layer of PEDOT:MoO3 helps to improve both the film hydrophobicity and the carrier extraction. A high efficiency improvement of about 30% is obtained in the interface‐modified laminating flexible ITO‐free OSCs compared to the conventional laminated device. This work illustrates that anode interface engineering has a significant effect on the improvement of performance of roll‐to‐roll laminated and self‐encapsulated OSCs.

Author(s): Lebens-Higgins, Z; Chung, H; Temprano, I; Zuba, M; Wu, J; Rana, J; Mejia, C; Jones, MA; Wang, L; Grey, CP; Du, Y; Yang, W; Meng, YS; Piper, LFJ | Abstract: Interest in alkali-rich oxide cathodes has grown in an effort to identify systems that provide high energy densities through reversible oxygen redox. However, some of the most promising compositions such as those based solely on earth abundant elements, e. g., iron and manganese, suffer from poor capacity retention and large hysteresis. Here, we use the disordered rocksalt cathode, Li1.3Fe0.4Nb0.3O2, as a model system to identify the underlying origin for the poor performance of Li-rich iron-based cathodes. Using elementally specific spectroscopic probes, we find the first charge is primarily accounted for by iron oxidation to 4+ below 4.25 V and O2 gas release beyond 4.25 V with no evidence of bulk oxygen redox. Although the Li1.3Fe0.4Nb0.3O2 is not a viable oxygen redox cathode, the iron 3+/4+ redox couple can be used reversibly during cycling.

Yellow-emitting YAG:Ce transparent ceramic is recognized as an ideal color converter in high-power blue LEDs and LDs, but the absence of scattering centers in its microstructure leads to a low light extraction efficiency and poor light uniformity. Here, taking advantage of the scattering effect and the transparency of YAG:Ce ceramics, Ce-free YAG phase was used as a second component to form a composite with YAG:Ce phosphor. The sintered YAG:Ce-YAG ceramic possessed a high transparency of ∼63 % and a thermal conductivity of 8.9 Wm−1 K−1. Due to its beneficial thermal properties and high external quantum efficiency of 70.2 %, the YAG:Ce-YAG ceramic could be excited under a high blue-laser flux density of up to 9.60 W/mm2 and showed a luminous emittance of 1220 lm/mm2. Due to light scattering arising from the slightly different refractive indices of the two phases, the designed YAG:Ce-YAG ceramic showed better lighting effects than a single-phase transparent YAG:Ce ceramic.

Metal halide perovskites have been extensively studied recently by virtue of their extraordinary luminescence characteristics. However, they still suffer from severe stability issues, and contain a toxic metal lead. Here, single crystals of (PEA)4Cu4I4, a lead-free orange-red-emitting organic–inorganic copper-halide compound with a photoluminescence quantum yield (PLQY) of 68%, were synthesized via a simple solvent vapor diffusion process with commercially-available phenylethylamine (PEA) as a ligand. The crystals show superior stability to perovskites with retaining 60% of their initial photoluminescence (PL) intensity after 60 days in water, which is due to the hydrophobic nature of PEA and the stable Cu–N bonds. Phase transition is found to take place upon lowering the temperature, which causes a redshift of the PL peak. The emission band is identified to be associated with triplet cluster-centered (CC) excited states because of their shortened Cu–Cu distances, excitation-independent PL and long PL lifetime. In addition, micron-sized oleic acid capped (PEA)4Cu4I4 particles were developed by a hot-injection method, and they possess similar stability to that of bulk crystals. A monochrome LED was further fabricated by employing the as-prepared micron-sized particles as phosphors, demonstrating their potential for optoelectronic applications.

Carbon dots (CDs), possessing unexpected advantages of photostability, biocompatibility and low toxicity, are regarded as novel nanomaterials in fluorescence (FL) imaging. Doping Gd element in CDs makes them have the ability to be used for magnetic resonance (MR) and FL imaging simultaneously. However, CDs reported before exhibit obvious defects like low photoluminescence (PL) quantum yield (QY) or biotoxicity. In this work, we use gadolinium meglumine, a material with relatively low biotoxicity, along with citric acid and diethylenetriamine to synthesize Gd-doped CDs (Gd-CDs) by a one-step hydrothermal method. The prepared Gd-CDs exhibit excitation-independent emission with a PL QY of 78.05% and a longitudinal relaxivity of 7.37 mM-1 S-1, which endows the composite with high-performance in MR/FL imaging. Meanwhile, the FL intensity of Gd-CDs remains stable in the presence of multiple amino acids, which indicates that the FL imaging effect should not be impacted significantly in microenvironments in vivo. In addition to the inconspicuous cytotoxicity, Gd-CDs could be used efficiently for dual-modal molecular imaging to detect diseases such as tumors in the early stages.

Copper oxide has aroused great concern in energy storage fields due to its properties of high theoretical capacitance, low cost and mild toxicity. However, its wide application still remains challenges owing to its poor electrical conductivity and unstable cycling life. Binder-free foam electrodes possess abundant porous structures and high specific surface area, which could get good contact with electrolyte. Herein, we demonstrate Ag nanoparticles decorated CuxO nanowires grown spontaneously on copper foam (CF) electrode for asymmetric supercapacitor. The skeleton structure of CF provides large amounts of active sites for the growth of CuxO nanowires. Moreover, Ag nanoparticles further decrease the internal resistance and enhance the electrochemical performance. Ag/CuxO/CF-40 electrode presents a high area specific capacitance of 1192 mF cm−2 at 2 mA cm−2 and the influence of surface capacitance-dominated process and diffusion-controlled process are discussed in detail. Besides, the energy density of the as-prepared asymmetric supercapacitor (ASC) reaches 46.32 μWh cm−2 at a power density of 3.00 mW cm−2. A 2V LED is lighted successfully by two ASC in series. This work provides a new strategy to prepare low internal resistance and binder-free flexible Ag/CuxO/CF electrode, which demonstrates a good potential application in flexible supercapacitors or other wearable electronic devices.

Fingerprints form when fingers touch a solid surfaceand are considered the best way for individual identification. However, the current latent fingerprint (LFP) developing methods cannot meet the demand for high sensitivity and being convenient and healthy. Herein, bifunctional Fe3O4@SiO2-CsPbBr3 powders have been designed and fabricated and exhibit good magnetic and strong fluorescent properties. The magnetism of Fe3O4 can avoid dust flying, while the fluorescence of CsPbBr3 ensures the high definition of LFPs. Clear fingerprints have been detected on various solid substrates using the Fe3O4@SiO2-CsPbBr3 powders instead of eikonogen. Detailed characterization studies suggest that the ammonium cationic groups on the surface of nanoparticles (NPs) have strong adhesive interactions with the residues of fingerprints because of the electrostatic attraction between them. Therefore, the convenient operation and excellent resolution offer great opportunity in the practical application of fingerprint detection and other areas.

In order to study the process of Fe3O4 reduction by melt electro-deoxidation. Electrochemical method was used to analyze the reduction mechanism of Fe3O4 in NaCl-CaCl2 melts. The effects of cell voltage and time on the product were discussed through constant cell voltage electrolysis. The results showed: (1) The reduction of solid Fe3O4 to metallic Fe is a two-step process for obtaining electrons. (2) The transformation process (600 min, 0–1.0 V) of the electrolysis products with the increase of the cell voltage is as follows: Fe3O4 → FeO → FeO + Fe → Fe. (3) The intermediate product Ca2Fe2O5 was formed (2.0 V, 10–300 min), which inhibited the deoxygenation process in the early stage of the reaction. When the electrolysis time exceeds 60 min, the main reaction is the reduction of Ca2Fe2O5 to Fe.

Summary To simulate the drying process of cut tobacco in a batch rotary dryer, six different models of equilibrium moisture content were selected to calculate the driving force of mass transfer, and a mathematical model of heat and mass transfer was numerically solved. The multi-objective nonlinear problem of heat and mass transfer coefficients was optimized by employing a weight factor. The simulation results showed that the weight factor r was an important parameter for fitting results of moisture content and temperature. The model evaluation indices almost reached their minimal values with r at 0.1. For all the six equilibrium/classic models the fit was better for moisture content than for temperature. One model (M-Hen/C) was superior to other equilibrium/classic models and the REA (reaction engineering approach) model. This study aims for an understanding of heat and mass transfer in the tobacco drying process, and provides a theoretical framework to support the prediction of temperature and moisture in various drying situations.

In this study, Y2O3–Al2O3–SiO2 (YAS) glass was prepared from Y2O3, Al2O3, and SiO2 micron powders. Thermal expansion coefficient of as-obtained YAS glass was about 3.9 × 10−6, matching-well with that of SiCf/SiC composites. SiCf/SiC composites were then brazed under pressure-less state by YAS glass and effects of brazing temperature on microstructures and properties of resulting joints were investigated. The results showed that glass powder in brazed seam sintered and precipitated yttrium disilicate, cristobalite, and mullite crystals after heat treatment. With the increase in temperature, joint layer gradually densified and got tightly bonded to SiCf/SiC composite. The optimal brazing parameter was recorded as 1400 °C/30 min and shear strength of the joint was 51.7 MPa. Formation mechanism of glass-ceramic joints was proposed based on combined analysis of microstructure and fracture morphology of joints brazed at different temperatures. Thermal shock resistance testing of joints was also carried out, which depicted decline in shear strength with the increase of thermal shock times. The strength of the joint after three successive thermal shock cycles at 1200 °C was 35.6 MPa, equivalent to 69% of that without thermal shock.

Despite the marked progress in recent years, structured light-based three-dimensional (3D) measurement techniques still have difficulty in capturing mirror surface reflection. The accuracy of 3D reconstruction for mirror objects should be further improved to adapt to the high reflectivity and curvature of such objects. To improve the stripe definition and reconstruction accuracy of highly reflective mirror objects, this paper analyzes the local blur of defocus stripes in phase measuring deflectometry (PMD) system, and presents a method to analyze the spatially varying defocusing and de-blurring, with the aid of a 3D block matching algorithm, thereby focusing on defocus stripes. Experimental results show that the proposed method can achieve micron-level reconstruction accuracy of standard flat mirrors, and detect the defects on highly reflective mirror objects at a high precision.

Low-dimensional metal halide hybrids (OIMHs) have recently been explored as single-component white-light emitters for use in solid-state lighting. However, it still remains challenging to realize tunable white-light emission in lead-free zero-dimensional (0D) hybrid system. Here, a combination strategy has been proposed through doping Sb3+ enabling and balancing multiple emission centers toward the multiband warm white light. We first synthesized a new lead-free 0D (C8NH12)6InBr9·H2O single crystal, in which isolated [InBr6]3- octahedral units are separated by large organic cations [C8NH12]+. (C8NH12)6InBr9·H2O exhibits dual-band emissions with one intense cyan emission and a weak red emission tail. The low-energy ultrabroadband red emission tail can be greatly enhanced by the Sb3+ doping. Experimental data and first-principles calculations reveal that the original dominant cyan emission is originated from the organic cations [C8NH12]+ and that the broadband red emission is ascribed to self-trapped excitons in [In(Sb)Br6]3-. When the Sb concentration is 0.1%, a single-component warm white-light emission with a photoluminescence quantum efficiency of 23.36%, correlated color temperature of 3347 K, and a color rendering index up to 84 can be achieved. This work represents a significant step toward the realization of single-component white-light emissions in environmental-friendly, high-performance 0D metal halide light-emitting materials.

Multidrug-resistant (MDR) bacteria-induced infections are becoming challenging issues threatening human health and life. Current antibiotics can hardly tackle this problem. Herein, we present a strategy to prepare mercaptophenylboronic acid (MBA)-activated gold nanoparticles (Au NPs) as an antibacterial agent against MDR bacteria. Both Au NPs and MBA cannot serve as antibiotics. However, when MBA attaches on Au NPs, the Au_MBA NPs show potent antibacterial activities against Gram-positive MDR clinical isolates (e.g., MDR Staphyloccocus aureus, MDR S. aureus; MDR Staphyloccocus epidermidis, MDR S. epidermidis). Furthermore, Au_MBA NPs show an extremely high median lethal dose (LD50,i.v., 960 mg/kg), which is much higher than those of most of the clinically used antibiotics. As an application example, we dope Au_MBA NPs with electrospun poly(e-caprolactone) (PCL)/gelatin nanofibrous membranes as wound dressings, which show striking ability to remedy S. aureus- or MDR S. aureus-infected full-thickness skin wounds on rats. Our study provides a novel strategy for treating MDR bacteria-infected wounds in a simple, low-cost, and efficient way, which holds promise for broad clinical applications.

Epitaxial Fe3O4 thin films grown on single crystal MgO(001) present well-defined model systems to study fundamental multivalent ion diffusion and associated phase transition processes in transition...

Ti3SiC2, as ternary layered ceramic with good electrical and thermal conductivity, has great application potential in the field of absorbing materials. Absorbing materials are also increasingly required to be lightweight, ultrathin, and flexible. Herein, Ti3SiC2/poly (TEP, DOP and PVB) composite film was biomimetically designed and fabricated by type casting process. As-fabricated composite film with 38% content of Ti3SiC2 was only 1.62 mm in thickness but exhibited excellent absorbing performance. The maximum reflection loss value of Ti3SiC2-based films was as high as −38.41dB and absorption bandwidth below −10 dB was 2.480 GHz. Polymer matrix wrapped around Ti3SiC2 not only enhanced the flexibility of the film, but also regulated its impedance matching and complex dielectric constant compared with pure Ti3SiC2. Superior wave absorption and flexibility imply excellent potential of this Ti3SiC2-based composite film for eliminating electromagnetic interference.

Ti3C2TX MXenes have great application prospects in the electromagnetic shielding field owing to their unique accordion structure and excellent electrical conductivity. However, understanding the correlation between their thermal stability and electromagnetic shielding performance is still lacking. Additionally, owing to the complex etching environment, some termination groups are present on the surface of MXenes, significantly affecting their thermal and electromagnetic performance. Here, to solve these problems, a heat treatment process was used. In this study, the effect of heat treatment on the removal of these surface adsorption groups was evaluated. Moreover, the evolution of structure, phase, and electromagnetic shielding properties of MXenes with the change in heat treatment temperature was also studied in detail. After heat treatment at 1100 °C, the phase of MXenes changed. Multilayer-TiC, a derivative of MXenes, still exhibited excellent shielding performance, which can be attributed to the elimination of surface end groups, the maintenance of multiple structure, and the increase in content about amorphous C. The total and absorbing shielding effectiveness reached 76.1 dB and 61.3 dB, respectively. Its conductivity was 265 S/m. This study is valuable in studying application prospects of Ti3C2TX MXene in high temperature fields, such as the field of electromagnetic shielding.

We investigated the evolution of ferromagnetism in layered Fe3GeTe2 flakes under different pressures and temperatures using in situ magnetic circular dichroism (MCD) spectroscopy. We found that the rectangular shape of the hysteresis loop under an out-of-plane magnetic field sweep can be sustained below 7 GPa. Above that pressure, an intermediate state appears in the low-temperature region signaled by an 8-shaped skewed hysteresis loop. Meanwhile, the coercive field and Curie temperature decrease with increasing pressures, implying the decrease of the exchange interaction and the magneto-crystalline anisotropy under pressures. The intermediate phase has a labyrinthine domain structure, which is attributed to the increase of the ratio of exchange interaction to magneto-crystalline anisotropy based on Jagla's theory. Moreover, our calculations reveal a weak structural transition around 6 GPa that corresponds to a significant change in the FeI-FeI bond length, which has strong influences on magnetic interaction. Detailed analysis on exchange interaction and magneto-crystalline anisotropy with pressure shows a consistent trend with experiments.

Thermally robust phosphor ceramics are an ideal color converter for high-power laser lighting applications. However, high-quality white light is different to achieve due to the absence of green and...

Circularly polarized light carries light spin angular momentum, which may lead helicity-resolved Raman scattering to be sensitive to the electronic spin configuration in magnetic materials. Here, we demonstrate that all Raman modes in the 2D ferromagnet VI3 show different scattering intensities to left and right circularly polarized light at low temperatures, which gives direct evidence of the time-reversal symmetry breaking. By measuring the circular polarization of the dominant Raman mode with respect to the temperature and magnetic field, the ferromagnetic (FM) phase transition and hysteresis behavior can be clearly resolved. Besides the lattice excitations, quasielastic scattering is detected in the paramagnetic phase, and it gradually evolves into the acoustic magnon mode at 18.5 cm-1 in the FM state, which gives the spin wave gap that results from large magnetic anisotropy. Our findings demonstrate that helicity-resolved Raman spectroscopy is an effective tool to directly probe the ferromagnetism in 2D magnets.

Determining the role of lattice oxygen in the oxygen evolution reaction (OER) is pivotal to understanding reaction mechanisms and predictive design of electrocatalysts based on transition metal oxi...

Fluidised bed technology is a very common industrial process and has a wide range of applications in process engineering. Though indirectly, a common way to infer the end product uniformity is through investigating the solid residence time distribution (RTD) in the system. A good understanding of the particle RTD is crucial for the proper design, optimisation, and scale-up of a fluidisation process. Flexible ribbon particles have a very different flow behaviour in a fluidised bed compared to that of spheres which in turn influences the RTD of the particles. However, this issue is still not very well addressed to date. In this paper, a double chain model is adopted to model cut tobacco strips in a fluidised bed riser. The spring constants of this chain model are calibrated, and the model is validated against experimental datum. Finally, the particle RTD as a function of different process parameters is investigated.

The high surface energy of nanomaterials endows them a metastable nature, which greatly limits their application. However, in some cases, the degradation process derived from the poor stability of nanomaterials offers an unconventional approach to design and obtain functional nanomaterials. Herein, based on the poor stability of ZnSe-[DETA]0.5 hybrid nanobelts, we developed a new strategy to chemically graphitize and functionalize graphene oxide (GO). When ZnSe[DETA]0.5 hybrid nanobelts encountered a strong acid, they were attacked by H+ cations and could release highly reactive Se2− anions into the reaction solution. Like other common reductants (such as N2H4·H2O), these Se2− anions exhibited an excellent ability to restore the structure of GO. The structural restoration of GO was greatly affected by the reaction time, the volume of HCl, and the mass ratio between GO and ZnSe[DETA]0.5 nanobelts. By carefully controlling the reaction process and the post-processing process, we finally obtained several Se-based reduced GO (RGO) nanocomposites (such as ZnSe/Se-RGO, ZnSe-RGO, and Se-RGO) and various selenide/metal-RGO nanocomposites (such as Ag2Se-RGO, Cu2Se-RGO, and Pt-RGO). Although the original structure and composition of ZnSe[DETA]0.5 nanobelts are destroyed, the procedure presents an unconventional way to chemically graphitize and functionalize GO and thus provides a new material synthesis platform for nanocomposites.

Hematite (Fe2O3) is a well-known oxide semiconductor suitable for photoelectrochemical (PEC) water splitting and industry gas sensing. It is widely known that Sn doping of Fe2O3 can enhance the device performance, yet the underlying mechanism remains elusive. In this work, we determine the relationship between electronic structure, optical properties, and PEC activity of Sn-doped Fe2O3 by studying highly crystalline, well-controlled thin films prepared by pulsed laser deposition (PLD). We show that Sn doping substantially increases the n-type conductivity of Fe2O3, and the conduction mechanism is better described by a small-polaron hopping (SPH) model. Only 0.2% Sn doping significantly reduces the activation energy barrier for SPH conduction from at least 0.5 eV for undoped Fe2O3 to 0.14 eV for doped ones. A combination of X-ray photoemission, X-ray absorption spectroscopy, and DFT calculations reveals that the Fermi level gradually shifts toward the conduction band minimum with Sn doping. A localized Fe2+-like gap state is observed at the top of the valence band, accounting for the SPH conduction. Interestingly, different from the literature, only 0.2% Sn doping in Fe2O3 significantly improves the PEC activity, while more Sn decreases it. The improved PEC activity is partially attributed to an increased band bending potential which facilitates the charge separation at the space charge region. The reduced activation energy barrier for SPH will facilitate the transport of photoexcited carriers for the enhanced PEC, which is of interest for further carrier dynamics study.

Vacancy-ordered double perovskites, having a great application in optoelectronic and thermoelectric devices, are variants of metal-halide perovskites. The PBE and HSE06 functionals for the first-pr...

The dissolution characteristics and electrochemical reduction mechanism of oxides of refractory metals ZrO2, HfO2 and MoO3 in NaCl-KCl-NaF melts are studied. The results shows that there are no chemical reaction of ZrO2 and HfO2 in NaCl-KCl-NaF melts, the dissolution of MoO3 is chemically dissolved, and MoO3 reactwith melts to form Na2Mo2O7. The reduction process of zirconium in the NaCl-KCl-NaF-ZrO2 melts is a reversible process of one-step electron transfer controlled by diffusion. The electrochemical reduction process of ruthenium is a one-step reversible process and the product is insoluble; Electrochemical reduction of metallic molybdenum in melts is controlled by the diffusion and electron transfer process of active ion Mo2O27− . The electrochemical reduction process of the metal molybdenum in the melts is carried out in two steps.

As a new generation advanced display or projection technology, laser displays or projectors have attracted great attention owing to their ultra-high brightness, energy saving nature, brilliant image quality and/or large sizes. However, for laser displays or projectors without using three primary laser diodes, the lack of appropriate blue-laser-driven color converters is a big limitation and challenge. In this work, we propose to develop laminated phosphor-in-glass (PiG) films as laser-driven color converters for wide-color-gamut and high-brightness laser displays. The β-Sialon:Eu and CaAlSiN3-LiSi2N2-Si2N2O, Calson:Ce phosphors were chosen as the green and orange emitters, respectively, and were co-fired with glass frits on a sapphire substrate to form PiG films. No interfacial reactions between phosphors and glass were identified, and phosphor powders were uniformly distributed in the glass matrix. The phosphor content and the film thickness had an influence on the microstructure, luminance saturation and optical properties of the PiG films under laser light irradiation; both PiG films reached a maximum luminance saturation of 6.09 W mm−2 when their microstructures were optimized. The lamination architecture of the PiG films had a great impact on the optical properties of the laser-driven white light, and the maximum ones were achieved as the green-emitting PiG film was positioned on the orange-emitting film adhered to the sapphire substrate. Under 4.82 W mm−2 blue laser excitation, the laminated double-layer PiG films enabled the creation of white light with a wide color gamut of 107% NTSC, luminous efficacy of 74.44 lm W−1, luminous flux of 282.13 lm and color temperature of 7902 K. These results indicate that the laminated PiG films are promising color converters for use in high-power and wide-color-gamut laser displays or projectors.

The rapid development of portable spectrometers has evoked a large demand for minimized light sources; meanwhile, NIR phosphor-converted light-emitting diodes (NIR pc-LEDs) are an optimal choice due to their compactness and low cost. The phosphors used in NIR spectroscopy (NIRS) are required to have broadband emission and high quantum efficiency (QE) for a wider detection range and efficient photo-to-electricity conversion. Inspired by the structural tunability of Y3Al5O12 (YAG), we proposed to achieve broadband emission by crystal field engineering, i.e., indirectly regulating the crystal field strength of Cr3+via the co-substitution of Y3+–Al3+ by Ca2+–Si4+ in YAG. The crystal field strength experienced on Cr3+ decreased as the octahedron was distorted and enlarged by the co-substitution. A broadband NIR emission with a large full width at half maximum (FWHM) of 160 nm and a high internal quantum efficiency (IQE) of ∼75.9% was realized in Y3−xCaxAl5−xSixO12:0.6% Cr (x = 1). The suitability of the investigated NIR phosphor was demonstrated by fabricating an NIR pc-LED prototype, and the detection resolution was improved by 30% compared to that of a traditional white pc-LED. These results indicate the great potential of the Y2CaAl4SiO12:Cr phosphors for use in highly precise and sensitive NIR pc-LEDs.

Electromagnetic absorption and electromagnetic interference (EMI) shielding materials, especially absorption-based EMI shielding materials, are urgently desired to eliminate increasingly serious electromagnetic radiation pollution. Metal carbides exhibit great promise in realizing excellent EMI shielding owing to their outstanding electrical conductivity. However, because of the same reason, the electromagnetic wave reflection from the metal carbide films is hardly diminished and thereby metal carbides cannot realize absorption-based EMI shielding. Herein, metal carbide/Ni hybrid nanostructures are designed to realize electromagnetic absorption and absorption-based EMI shielding. The hybrid nanostructures are prepared by in situ reduction of Ni on metal carbide nanosheets. The loading of Ni greatly increases the impedance matching and attenuation constants. Metal carbide/Ni hybrids achieve a reflection loss of −41.7 dB at 10.8 GHz with a thickness of 1.8 mm. An EMI shielding effectiveness larger than 60 dB is achieved in the whole X-band with a metal carbide/Ni hybrid film of 50 μm. Particularly, the absorption contributes 98.9% of total EMI shielding effectiveness, indicating the absorption-based EMI shielding. In addition, the metal carbide/Ni hybrid film exhibits very good mechanical properties and long-term stability in water. Our findings are very important for the development of electromagnetic absorption and absorption-based EMI shielding materials.