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A series of novel Ca2LaZr2Al3O12: xCe3+garnet phosphors were obtained by conventional high temperature solid-state reaction. Crystal structure, phase purity, micromorphology as well as luminescence properties are studied via X-ray powder diffraction, scanning electron microscope and photoluminescence spectra including excitation and emission. Moreover, the mechanism of concentration quenching, thermal stability, fluorescent lifetime and quantum efficiency were investigated in detail. Under n-UV excitation, Ca2LaZr2Al3O12: Ce3+ exhibits a broadband of blue emission at 440 nm approximately for maximum, corresponding to 5d-4f transition of Ce3+. Emission can keep 41% of initial intensity when temperature is promoted to 373 K according to temperature-dependence emission spectra. The internal quantum efficiency of the optimal specimen is 15% and with Ce3+ increasing, the color of emission transfers to light from dark blue at CIE.

MgO-C refractories were prepared by using fused magnesia and flake graphite as main raw materials, adding metal aluminium powder as antioxidant, and using sucrose solution instead of phenolic resin as binder. The mechanical properties of MgO-C refractories obtained under different temperature conditions were studied and compared with those of phenolic resin bonded MgO-C refractories. The results show that CO2 and water vapor were mainly released from the solidified sucrose solution during the heating process, which can effectively solve the problem of harmful gases such as formaldehyde and phenol when the phenolic resin is heated. The MgO-C refractory material prepared by the sucrose solution as a binder has a good bonding strength after curing at 180 °C. The flexural strength and compressive strength of MgO-C refractories obtained by adding 6wt% sucrose solution are 4.90 MPa and 41 MPa. At high temperature, sucrose carbonization forms a strong carbon bonding, and the flexural strength of MgO-C refractories is 5.16 MPa and the compressive strength is 34 MPa, which is similar to the performance of the phenolic resin bonded MgO-C refractories.

In this study, novel MgO-C refractories using environmentally friendly sucrose as binder were prepared. To solve the harmful effects of formaldehyde and phenolic compounds that cause serious harm to the environment and human health released during the development, production and use of phenolic resin binders for MgO-C refractories, MgO-C refractories using environmentally friendly sucrose instead of phenolic resins as binders were prepared. The phase, microstructure, oxidation resistance and the antioxidant mechanism of MgO-C refractories prepared by adding sucrose as binder at different temperatures were analyzed. The formula between the weight loss of the material and the temperature is y=1.6225x+0.215 (600°C ∼ 1200°C). The addition of aluminium resulted in the formation of Al2O3 inside the refractories. Meanwhile, MgAl2O4 crystals were synthesized by Al2O3 and MgO at high temperature. The formation of Al2O3 and MgAl2O4 played an important role in improving the oxidation resistance property of MgO-C refractories using sucrose as binder.

The harmful components such as formaldehyde and phenolic compounds released during the development, production and use of MgO-C refractories prepared by using phenolic resin as a binder can cause serious harm to the environment and human health. In this paper, MgO-C refractory material with sucrose as binder and metal aluminium powder as antioxidant is prepared. Different slag temperature and time factors have a largely influence on the slag corrosion resistance of as-prepared samples. By analyzing the microstructure and composition of the samples, it is found that under the condition of constant time, the higher the temperature, the more obvious the slag corrosion phenomenon; under isothermal conditions, the longer the time, the more obvious the slag corrosion phenomenon. At the same time, it is revealed that the main corrosion process of MgO-C refractories prepared by adding sucrose as a binder is carbon oxidation and slag corrosion, which provides a theoretical basis for optimizing the slag resistance of MgO-C refractories.

Nanostructure reinforced nitride ceramics play an important role in the family of structural ceramics. In this study, large scale of one-dimensional (1D) β-sialon nanostructures and β-sialon-β-Si3N4 composite powders were synthesized simultaneously via a reduction nitridation process by using powders of silicon, aluminum, and silica as raw materials. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM/HRTEM), Fourier-transform infrared spectroscopy (FT-IR) and energy dispersive x-ray spectroscopy (EDS) were used to characterize the phase composition, morphology, and microstructure of the as-obtained products. As a result, large scale of 1D β-sialon nanostructures can be prepared at 1600 °C. The diameter of the as-prepared nanowires in the range of 80 to 170 nm can be tailored by the addition of aluminum. The growth of 1D β-sialon nanostructures is achieved by a vapor-solid (VS) mechanism. Photoluminescence (PL) of the 1D β-sialon nanostructures was characterized which exhibit violet/blue emission peaks, making it have the potential to be applied in optoelectronic nanodevices. Besides, nitride ceramic composite powders including β-Si3N4 and β-sialon with in situ formed β-sialon nanowires were also achieved. The phase transformation behavior and the thermodynamical analysis of the ceramic composite powders were also studied by characterizing the phase composition of the products synthesized at different temperature. The as-grown β-sialon nanowires and the composite powders have great potential to be applied in nanostructure reinforced structural ceramics.

Ba2FeMoO6 has been reported to exhibit a ferromagnetic to a paramagnetic transition with a Curie temperature above room temperature, and thus it is a potential material for spintronics. These exciting properties are related, at least in part, to combined structural and magnetic instabilities. A conventional analysis of lattice parameter data from the present study and literature in terms of spontaneous strain shows that the magnetic ordering is accompanied by a significant volume strain, which implies a strong coupling behavior of magneto-elastic properties in Ba2FeMoO6. In addition, to address the correlation between anti-site defects (ASD) and magnetic properties, we have carried out a comparative study of six cubic Ba2FeMoO6 polycrystals with different degrees of ASD. The correlations among the Curie temperature, low-temperature saturation magnetism, and ASD are discussed in detail using a combination of diffraction and magnetic measurements. This systematic study, especially the strain analysis, of Ba2FeMoO6 will facilitate its potential applications in the field of spin electronics and thin film engineering.

Phase change materials (PCMs) have been widely investigated for thermal energy storage due to their excellent heat storage densities and narrow operating temperature. However, their poor thermal conductivity and shape stability during utilization always restrict their further application. In this paper, polyethylene glycol/expanded perlite phase change materials with Cu powder phase-change materials (PEG-Cu/EP PCMs) are prepared by vacuum impregnation to overcome these problems. The results indicated that Cu particles are well dispersed in PEG and uniformly enwrapped inside the pores and surfaces of EP due to their excellent physical interactions by capillary force and surface tension. Thus the as-prepared composites exhibit superior shape stability around the working temperature around 253 °C. Furthermore, when 9.35% Cu powders are added into PEG, its thermal conductivity of corresponding composite is significantly enhanced by 129.9%, with a nearly invariable phase change enthalpy at the same time. Therefore, the PEG-Cu/EP PCMs are confirmed to be promising energy storage materials for applications in solar energy generation, building energy conservation, and industrial waste heat utilization.

Expanded graphite/β-SiC nanowires composites (ESNC) were prepared through chemical vapor deposition, and paraffin/expanded graphite/β-SiC nanowires composites (PESNC) were made through vacuum impregnation to overcome liquid leakage during phase transition and enhance the thermal conductivity of paraffin. Fourier transform infrared spectroscopy showed no chemical interactions between the paraffin and ESNC. Differential scanning calorimetry estimated the temperature and latent heat of PESNC during melting to 45.73 °C and 124.31 J g−1, respectively. The respective values of these quantities during freezing were recorded as 48.93 °C and 124.14 J g−1. The thermal conductivity of PESNC was estimated to 0.75 W mK−1, which was 3.26-folds that of pure paraffin (0.23 W mK−1). PESNC perfectly maintained its phase transition after 200 melting–freezing cycles. The resulting ideal thermal conductivity, good chemical stability, thermal properties and thermal reliability of PESNC are promising for use in energy efficient buildings and solar energy systems.

Transparent and flexible electrodes on cost effective plastic substrates for wearable electronics have attract great attention recently. Due to the conductivity and flexibility in network form, metal nanowire is regarded as one of the most promising candidates for flexible electrode fabrication. Prior to application, low temperature joining of nanowire processes are required to reduce the resistance of electrodes and simultaneously maintain the dimensionality and uniformity of those nanowires. In the present work, we presented an innovative, robust and cost effective method to minimize the heat effect to plastic substrate and silver nanowires which allows silver nanowire electrodes been directly written on polycarbonate substrate and sintered by different electrolyte solutions at room temperature or near. It has been rigorously demonstrated that the resistance of silver nanowire electrodes has been reduced by 90% after chemical sintering at room temperature due to the joining of silver nanowires at junction areas. After ∼1000 bending cycles, the measured resistance of silver nanowire electrode was stable during both up-bending and down-bending states. The changes of silver nanowires after sintering were characterized using x-ray photoelectron spectroscopy and transmission electron microscopy and a sintering mechanism was proposed and validated. This direct-written silver nanowire electrode with good performance has broad applications in flexible electronics fabrication and packaging.

Herein, ultralong silicon nitride nanowires were synthesized via a chemical vapor deposition method by using the low-cost quartz and silicon powder as raw materials. Simple processes were used for the fabrication of disordered and ordered nanowire membranes of pure silicon nitride nanowires. The nanowires in the disordered nanopapers are intertwined with each other to form a paper-like structure which exhibit excellent flame retardancy and mechanical properties. Fourier-transform infrared spectroscopy and thermal gravity analysis were employed to characterize the refractory performance of the disordered nanopapers. Highly ordered nanowire membranes were also assembled through a three-phase assembly approach which make the Si3N4 nanowires have potential use in textured ceramics and semiconductor field. Moreover, the surface nanowires can also be modified to be hydrophobic; this characteristic make the as-prepared nanowires have the potential to be assembled by the more effective Langmuir–Blodgett method and also make the disordered nanopapers possess a super-hydrophobic surface.