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Abstract: This work firstly focuses on the thermodynamic and kinetic studies of the liquid phase separation in the Cu–Cr–Si ternary system. On the thermodynamic aspect, four isothermal sections of the Cu–Cr–Si system at 900°C, 1000°C, 1100°C and 1200°C have been experimentally determined by X-ray diffraction (XRD) and electron probe microanalyzer (EPMA) on the equilibrated alloys, and the phase equilibria in the Cu–Cr–Si ternary system has been thermodynamically assessed by using the CALPHAD (Calculation of Phase Diagrams) technique on the basis of the presently obtained experimental results. The addition of Si can stabilize the metastable liquid phase separation in the Cu–Cr binary system, and increase its critical temperature. On the kinetic aspect, the formation of top–bottom and core–shell separated morphologies of the as-cast liquid immiscible Cu–Cr–Si alloys under various cooling rates have been detailedly analyzed. [Copyright &y& Elsevier]

Abstract: The phase equilibria at 900°C, 1000°C, 1100°C, 1200°C and 1300°C in the Cu–Mo–Ni system were experimentally determined by means of optical microscopy (OM), electron probe microanalyzer (EPMA) and X-ray diffraction (XRD) on the equilibrated alloys. The experimental results firstly found that the fcc-type miscibility gap exists at 900°C, 1000°C, 1100°C and 1200°C in the Cu–Mo–Ni system, and the solubility of Cu in the MoNi phase at 900°C, 1000°C, 1100°C and 1200°C are about 0.5at.%, 1.5at.%, 1.7at.% and 4.0at.%, respectively. The as-cast Cu20Mo20Ni60 (at.%), Cu20Mo30Ni50 (at.%), Cu10Mo60Ni30 (at.%), Cu70Mo10Ni60 (at.%), Cu20Mo60Ni20 (at.%) and Cu80Mo10Ni10 (at.%) alloys appear the separated macroscopic morphologies, which are caused by the liquid phase separation on cooling, while the as-cast Cu10Mo25Ni65 (at.%), Cu32Mo5Ni63 (at.%) and Cu30.7Mo6.3Ni63 (at.%) alloys show the homogenous microscopic morphologies. On the basis of the experimental data investigated by the present and previous works, the phase equilibria in the Cu–Mo–Ni system were thermodynamically assessed by using CALPHAD (Calculation of Phase Diagrams) method, and a consistent set of the thermodynamic parameters leading to reasonable agreement between the calculated results and experimental data was obtained. [Copyright &y& Elsevier]

Rare earth Eu-doped lead zirconium titanate (PEZT) nanocrystalline powders with a composition near the morphotropic phase boundary (Zr/Ti=52/48) were prepared by a modified sol–gel method. DTA/TG, IR and XRD were used to determine the thermal and phase changes in the formation of PEZT crystalline powders. The maximal doping content of Eu and the effect of Eu3+ cation substitution for Pb2+ cation on the microstructure of PZT were developed with XRD. The grain size of PEZT nanopowders is about 20 nm determined by TEM. [Copyright &y& Elsevier]

Developing high-efficiency photocatalyst for the degradation of environmental pollutants under visible light is ideal. In this study, indium-doped zinc oxide with rich oxygen vacancy defects (In–OV–ZnO) was successfully fabricated by using a facile solution method followed by annealing process. The morphological, structural, and optical properties of the as-synthesized samples were studied. The X-ray diffraction measurements revealed the positions of the main peaks in the synthesized samples with In3+ ions and oxygen vacancies were slightly shifted. The analysis of SEM and TEM showed that the In–OV–ZnO samples were in the nanoscale regime (20-50 nm) with hexagonal crystalline morphology. The UV–vis DRS spectra showed that In–OV–ZnO samples had the band gap value of 3.14 eV. Based on photocurrent analysis and photoluminescence studies, the oxygen vacancy of In–OV–ZnO favored the electron–hole pairs' separation. Photocatalytic studies revealed that the In–OV–ZnO samples display better photocatalytic activities of methylene blue (MB) and methyl orange (MO) under visible light irradiation, which exhibited maximum degradations of 96.84% and 90.05%, respectively. The enhanced photocatalytic performance can be ascribed to the synergistic effect of the oxygen vacancy defects and the In3+ ions favoring efficient electron–hole separation, which provided several active sites. This work develops a study to enable an efficient and cost-effective design of novel photocatalysts and offers insight into the influence of surface defects in enhancing photocatalytic activity. Image 1074 • A oxygen defect-rich In-doped ZnO nanostructure was fabricated. • The prepared In-doped ZnO nanostructure exhibited excellent photocatalytic performance under visible light irradiation. • Oxygen vacancy and In3+ ions doping play an vital role in the improvement of photocatalytic performance. • Photodegradation mechanism of In–OV–ZnO photocatalysts is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Nanosized ZnO/lead zirconate titanate (ZnO/PZT) ceramic matrix composites were prepared by a traditional sintering process in this study. Dependence of the dielectric permittivity of the ZnO/PZT composites on frequency and temperature was studied. We observed the remarkable dependence of dielectric permittivity of the ZnO/PZT composites on the concentration of ZnO, frequency and temperature. A relatively high dielectric permittivity, which is more twice higher than that of pure PZT ceramics, was found in the ZnO/PZT composites. The results showed that the addition of nanosized ZnO had an obvious influence on the dielectric permittivity of the ZnO/PZT ceramics matrix composites. [Copyright &y& Elsevier]

A series of K 2 SiF 6 :0.066Mn4+@Cl-GQDs (KSF:K 2 SiF 6 , Cl-GQDs: Cl containing graphene quantum dots) phosphors were prepared with a H 2 O 2 -free hydrothermal method, and the optimal sample was KSF:0.066Mn4+@Cl-GQDs 8 mg/mol. Enhanced effects on luminescent intensity and thermal stability inducing by coating of Cl-GQDs are observed: (a) Integrated emission intensity is 4.60 times of that of KSF:0.066Mn4+, (b) The luminescent thermal stability is greatly enhanced, which integrated emission intensities at 180 and 240 °C are 282.9 and 135.3% of that at 30 °C, respectively. The mechanisms of the above behaviors are discussed and proposed: Coordination between conjugated large π bond of GQDs and Mn4+ leads to the enhancement of emission intensity and luminescent thermal stability. Thermal stability analysis results show that the optimal samples suitable for high power WLEDs. Warm white light with low correlated color temperature and high color rendering index was produced from prototype WLEDs using the optimal sample as red emitting component. Image 1 • K 2 SiF 6 :Mn4+@Cl-GQDs were synthesized with a H 2 O 2 -free hydrothermal method. • Emission intensity and thermal stability are dramatically improved by coating of Cl-GQDs. • Integrated intensity of PL can be enhanced 4.60 times by coating of Cl-GQDs. • Integrated PL intensities at 180 and 240 °C are 282.9 and 135.4% of that at 30 °C. [ABSTRACT FROM AUTHOR]