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ZnO/ZnFe2O4@reduced graphene oxide (RGO) nanocomposites have been successfully synthesized through annealing treatment of Zn/Fe MOF-5@GO composites. The ZnO/ZnFe2O4 nanoparticles with a diameter of 12–15 nm are evenly distributed on the surface of RGO. The ZnO/ZnFe2O4@RGO nanocomposites show superior rate capacity and cyclic stability of 655 mAh/g after 200 cycles at 0.2 A/g for lithium ion battery (LIB) anode. The superior electrochemical property benefits from the unique structure of ZnO/ZnFe2O4@RGO nanocomposites, which can provide a buffer space for volume expansion, and enhance conductivity in the charge/discharge cycle.

Inorganic scintillation materials have been widely used in several fields, such as high energy physics, nuclear medical imaging and industrial nondestructive inspection. In this work, a novel scintillation material, (CexLu1-x)3Al5O12/Al2O3 (Ce3+:LuAG/Al2O3) eutectic with different Ce3+-doping concentrations, was successfully grown by the micropulling down method at different pulling speeds. The effects of Ce3+-doping concentration and pulling speed on the microstructure and luminescent properties of the Ce3+:LuAG/Al2O3 eutectic were investigated. The eutectic has a typical garnet structure, and a “Chinese script” microstructure can be seen throughout the cross section. As the pulling speed increased, the grain size and the morphological appearance of the “Chinese script” microstructure decreases. The Ce3+:LuAG/Al2O3 eutectic shows a characteristic Ce3+ emission band centered at 508 nm, and the emission intensity increases with increasing Ce3+-doping concentration until the Ce3+-doping concentration reaches x = 0.01. The eutectic grown at a pulling speed of 1.7 mm/min shows maximum emission intensity, and the light yield of the (Ce0.01Lu0.99)3Al5O12/Al2O3 eutectic excited with X-ray at room temperature is approximately 64% of that of the (Ce0.01Lu0.99)3Al5O12 single crystal. The results reveal that the Ce3+:LuAG/Al2O3 eutectic has a potential application as an X-ray detector material.

In the present paper, an Al rod as liquid cathode was added into the SmF3-LiF-Sm2O3 molten salt system and subsequently the Al-Sm alloy was prepared by the liquid cathode electrolysis method. The effects of electrolysis temperature, cathode current density and electrolyte composition on the current efficiency were studied. The results demonstrated that the maximum content of Sm in the Al-Sm interalloy could reach up to 32.8 wt.%, whereas the alloy was mainly composed of the Al substrate, Al4Sm and Al3Sm phases. The current efficiency increased first subsequently decreased as the electrolysis temperature and cathode current density increased. Simultaneously, the electrolyte composition had a high impact on the current efficiency. When the mass ratio of SmF3and LiF was 4, the current efficiency was 62.8 %.

Yb3+/Mn4+ co-doped La2ZnTiO6 (brief as LZT:Yb3+/Mn4+) phosphors with xYb3+ (x = 0–0.12) and yMn4+ (y = 0–0.01) doping concentrations have been synthesized via a sol-gel method. X-ray diffraction (XRD) and photoluminescence spectra were employed to characterize the properties of final products. The LZT:Yb3+/Mn4+ material can efficiently convert the short-wavelength sunlight in wide spectral ranges (250–600 nm) into near-infrared emission around 990 nm which matches the higher photosensitivity region of Si-based solar cells. A dipole-dipole interaction plays an important role for the energy transfer process from Mn4+ to Yb3+ ions, which has been verified by Dexter's theory. Under the 390 nm excitation, the energy transfer efficiency is 38.6% in the La1·9ZnTi0·998O6:0.1Yb3+/0.002Mn4+ co-doped sample. Due to the effective absorption of Mn4+ in the visible region and charge transfer transitions (O2−→Yb3+ and O2−→Mn4+) in the UV region for LZT and the efficient energy transfer to Yb3+, this material can be developed as spectral convertors to improve silicon solar cell photovoltaic conversion efficiency.

(Gd1-xTbx)3(Al1-yGay)5O12(x = 0.02–0.4, y = 0.2–1) garnet green phosphors were synthesized through the solid-state reaction method. The phase analyses and luminescence properties of phosphors were investigated as a function of the Ga3+ admixture content with the aim of development of thermal stable and efficient green phosphors. The results show that pure garnet was synthesized only when the Ga3+ content is high enough(y ≥ 0.4) and the optimal content of Tb3+ was 10 at.% Tb3+ (x = 0.1). The spectra intensity and the thermal stability of phosphors strongly depend on the Ga3+ content. The (Gd0.9Tb0.1)3(Al0.6Ga0.4)5O12 phosphor has maximum emission intensity with a high quantum efficiency about 87.72%, and it has best thermal stability with a highest quenching temperature of 488 K. Therefore, the (Gd0.9Tb0.1)3(Al0.6Ga0.4)5O12 phosphor is potential to be served as green phosphors in lightings and displays.

A novel Mg-rare earth (Nd,Ce) coating containing intermetallic compound was fabricated on the surface of the AZ91D magnesium alloy by bathing the sample in a NaCl-KCl-LiCl-NdCl 3 -CeCl 3 molten salt. The cross-sectional morphology, microstructure and phase composition of the coating were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). The corrosion resistance was characterized by the potentiodynamic polarization curves. The SEM observation indicated that a continuous and compact diffusion coating was obtained on the surface of SMATed AZ91D magnesium alloy and the XRD and TEM investigations revealed that the new phases were Al 2 Ce and Al 2 Nd intermetallic. The potentiodynamic polarization curves showed that the Mg-RE coating improved the corrosion resistance of the AZ91D magnesium alloy, and the corrosion current density of the coated sample was about 1510 mA/cm 2 lower than the uncoated sample.

Mechanism for the formation of core-shell ATO-TiO2 was investigated. Zeta potential, XRD, TEM, XPS and LCR digital bridge were employed to characterize the morphology, phase structure, surface composition and conductivity of samples. Results indicated that the formation of ATO-TiO2 is through a synergistic effect between dispersive force and electrostatic repulsion, and this synergistic effect reaches the optimum status at pH = 2. Results obtained from theoretic calculation suggested that the ATO surrounded on TiO2 is in particle form, and the formation mechanism could be depicted by an “islands-on-sphere” model.

Antimony doped tin-oxide powders were prepared by controlled precipitation. Surface compositions were determined by X-ray photoelectron spectroscopy (XPS). The results indicate that enrichment of dopant at the surface of nanoparticles depends on total doping concentration and annealing temperature. Doped antimony shows the tendency to diffuse to surface when annealing at high temperatures. But same amount of Sb atoms are retained on the surface for powders annealing at different temperatures. The higher enrichment at higher temperature is caused by the decreasing of surface areas. Variation of the conductivities of SnO2 powders is also discussed.