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The non-uniform plating-stripping behaviours of Li metal anodes hinder the application of Li metal batteries. Here, a stable 3D matrix is designed by coating a carbon skeleton with MXene, and the significant influence of the crystallographic texture of Li metal on electrochemical behaviour is investigated. The results demonstrate that the 3D MXene/carbon skeleton can effectively induce the evolution of advantageous Li(110) facets with a dendrite-free anode interface. Consequently, the modified Li metal anodes deliver stable plating-stripping behaviours.

Herein, the obtained Cu

CsPbBr

Herein, the optional and controllable growth of Bi

Via a novel mechanical cleavage technology, TiNbO5 − (TNN) nanosheets are obtained from the corresponding layered compound. X-ray diffraction pattern is employed to determine the phase transformation of the specimens during the whole process, and the microstructure of the samples is analyzed by scanning electron microscope, transmission electron microscope, and atomic force microscope. The results indicate that the compression and shearing of the designed rolling machine play an important role in the crack and the exfoliation of the aggregated layered compound. Subsequently, the TNN nanosheets with the 0.91 nm thickness have been successfully fabricated with the assist of microwave and ultrasonic technique. With the layer by layer technique, (Polyetherimide/TNN) n films are deposited on the substrate with glass. It is found that the multilayer film with ten cycles treated at 450 °C exhibited photo-induced hydrophilicity under ultraviolet irradiation and high photocatalytic oxidation activity. The outstanding self-cleaning ability of the TNN nanosheets coated glass can be seen from the appearance photograph by naked eyes.

Visible-light-driven organic transformations have received much attention because of their low cost, relative safety, and environmental friendliness. In this work, we report a series of Bi

ZnO materials have being researched in recent 30 years as a hot topic. ZnO is a third generation of semiconductor, it can be prepared into various forms of films and nanostructures, and they have excellent optical properties, electrical properties and magnetic properties. Because the polar ZnO’s quantum wells have a strong electric field, this will have a great impact on its optical properties. But non-polar ZnO has reduced such a strong electric field, so it greatly improved the luminescent performance. It’s more excellent than polar ZnO in the optical performance. In recent years, non-polar ZnO thin films’ research became increasingly evident. This article summed up the performances, preparations and applications of non-polar ZnO, and there are some suggestions. All of these are good to the further study of non-polar ZnO.

In this work, the mechanical properties, such as Vickers microhardnessHv, fracture toughnessKc, yield strengthσvand brittleness indexBi, of oriented 6H-SiC crystal are systematically evaluated using a microindentation technique under 0.1-2 kg applied load. It is found theHvis decreased as the applied load is increased which is mainly attributed to the effect of indenter penetration. TheHvvalue can be effectively presumed by Kicks law and the Meyers indexnis determined to be 1.73. However, theKcvalue is measured nearly a constant (~0.148 MPa.m1/2) which reveals the toughness of 6H-SiC(0001)crystal is much weaker than those of Si(100)and GaAs(100)crystals. The variation ofσvto the load is similar to that ofHv. The brittleness indexBialso exhibits deceasing tendency as the applied load is added.

The crack behavior of Si-doped GaAs crystals produced by a novel pulling-down method was investigated. Some cracks were observed in the crystal tail part and no twins or polycrystals were observed. The cracking mechanism was discussed considering the growth parameters, such as the pulling-down rate, annealing time and cooling speed of the furnace. The crystal was easily broken if the cooling rate was too fast. To avoid cracking, the temperature profile and the growth parameters had been optimized. The cleavage property of the GaAs crystal was strongly related to its atomic arrangement and corresponding electron density map. Ultrasonic vibration or mechanical machine would make the crystal cleaved along (110) plane. GaAs crystal displayed a strong anisotropic crack property under the force of microindentation test.

Compound semiconductor GaAs crystal was grown by the pulling-down method and the Φ2" GaAs boules were obtained. The growth defects, such as growth stripes, small facets, pits and dislocations, were observed. The pits on the surface of the boule was attributed to the water content of B2O3 encapsulant and the growth defects on the tail were associated with the evaporation of As due to GaAs decomposition. The average EPD (etch pit density) was measured less than 5000 cm-2, which shows the pulling-down method was a potential technique to grow high quality GaAs crystals.

Undoped GaAs single crystal has been grown in PBN crucibles by the pulling-down method. The temperature profile of the furnace was optimized with a narrow melting zone and a small temperature gradient at the solid-liquid interface. Quartz ampoules were used to protect the evaporation of As during the growth and the deformation of the ampoule was discussed as a function of temperature, time and pressure differential. A Ø56 mm×70 mm GaAs crystal with nearly 100 % single crystalline yield was obtained. X-ray rocking curve analysis revealed the excellent crystalline quality. The average EPD and electrical properties of the crystal were tested comparable to those of the crystal produced by the VGF method. Therefore, the pulling down method was a feasible approach for GaAs crystal production.

The Shoushan Stone is one of the famous craft carving stones in China and transparency is one of the key indicators to evaluate the value of Shoushan Stone. The better the transparency is, the higher the value is. In this study, the mineral compositions and morphologies were investigated by XRD and SEM, respectively. Combining with the characterization of Shoushan Stone samples, the relationships between mineral composition, morphology and transparency were studied. The results show that the transparency of Shoushan Stone is determined by the mineral categories and microstructures. The sample with high transparency is fewer mineral composition numbers, similar mineral compositions and bigger crystal particles

Two kinds of Er-doped lithium phosphate glass have been chemically strengthened by ion exchange in a mixed binary melt of KNO3 and NaNO3 at temperature far below glass Tg. Ion depth profile has been determined with WDS technique. The effect of acid wash on surface morphology, hardness and fracture temperature of glass was investigated. It was found that acid wash following ion exchange could improve the surface morphology and strength of glass. Nevertheless, WDS analysis showed that the acid wash could cause the ion diffusion from glass surface to acid wash liquid, i.e. the back diffusion of K+ and Na+. The results revealed that the back diffusion of K+ was severer than that of Na+ during acid wash and the bond of K+ to glass network was weak.

As a professional with strong theoretical and practical in a new college, the guidance major-materials science and engineering involves extremely broad field. Our reform ideas and practices are only to training science-based applied talents possessing engineering capabilities. Facing the new situation on the demand for materials engineering personnel, we reform curriculum and teaching to get rid of the drawbacks of the original content and build the professional training program with the characteristics and course system.

The Shoushan Stone is one of the famous craft carving stones in China and the transparency is one of the decisive factors to appraise its value. The better the transparency is, the higher the value is. In this paper, the mineral compositions and morphology of some Shoushan Stone samples were investigated by XRD and SEM methods. Combining with the characterization of Shoushan Stone, the relationships between the morphology and the transparency of Shoushan Stone were studied. The results show that the transparency of Shoushan Stone samples was determined by their microstructures, such as the mineral particle sizes and its arrangement, the gaps and porosity. The Shoushan Stone samples with high transparency are those with good arrangement, bigger crystal particle and less porosity and gaps.

DSC measurements have been carried out for the as-quenched xNa2O- (15-x)Li2O-4B2O3-11Al2O3-5BaO-65P2O5 (x=0,3.75,7.5,11.25 and 15 mol%) glasses with different particle size. Two crystallization peaks appear on the DSC curves for sample sized 90-110μm. The presence of two crystallization peaks is due to different crystallization mechanisms, surface and bulk (internal) crystallization. The X-ray diffraction measurements are also employed to investigate the crystallization of glasses. The results show that bulk crystallization is difficult to occur in the studied phosphate glasses. The effect of mixed alkali on glass thermal stability is also studied in this paper. The surface and bulk crystallization active energies are calculated according to Kissinger equation.

Sr1-xNdxFe12O19 ferrites were Synthesized via sol–gel and self-combustion methods with Fe(NO3)3·9H2O，Sr(NO3)2 and citric acid. The as-synthesized powder was studied by differential scanning calorimeter (DSC). X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) were applied to investigate the structure and magnetic properties. The powder was synthesized in different calcination temperature and doping content of Nd2O3. The experiment reveals that the magnetic properties of Nd3+ doped ferrites are less sensitive to calcination temperature comparing with no doping ferrites. The coercivity (Hcj) of Nd3+ doped ferrites reach 423.96 kA·m-1.

11 oxides (MgO, CaO, BaO, TiO 2 , V 2 O 5 , MnO 2 , Fe 2 O 3 , CuO, ZnO, PbO 2 and B 2 O 3 ), often found in coal-derived carbon materials, were loaded into the coal-derived carbon material by two methods such as adsorbing oxides through solution onto the surface of coke and adding oxides into the coal before carbonization. The effects of oxides on carbon solution reaction of carbon material were investigated and compared. The results show that the effect trends are similar but the effect of oxides by adsorbing is remarkably greater than that of the oxides by adding oxides as BaO, MgO, Fe 2 O 3 , CuO, ZnO, MnO 2 , PbO 2 and B 2 O 3 . And the effect trends are similar. BaO, CaO and Fe 2 O 3 are the greatest affecting oxides. The saturation point of addition content is 3% and that of adsorption is 1%.