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In this work, a series of Al2O3–Ce:YAG phosphor powders were synthesized by regulating the excess Al3+ of (Y,Ce)3Al5O12 via coprecipitation method for the first time, where Al3+, Ce3+, and Y3+ elements were uniformly distributed. With the increase of Al3+ content, the morphology of the powders changed from wormlike shapes to flaky shapes, and Y3Al5O12 phases had a tendency to convert to YAlO3 phases. The x wt.% Al2O3–(Y0.999Ce0.001)3Al5O12 (x = 20, 30, 40, 50, 60, and 70) composite phosphor ceramics (CPCs) were obtained by vacuum sintering (1775°C × 10 h), where Al2O3 and Ce:YAG phases were also well‐distributed. When the Al2O3 content was 30–40 wt.%, the average grain size of Al2O3 was close to that of Ce:YAG. A solid‐state laser lighting device was constructed by a 450 nm laser source and CPCs in a reflection mode. By adjusting the laser power, the correlated color temperature (CCT) values of white laser diodes (LDs) were achieved close to the standard white light of 6500 K. Impressively, the white LDs equipped with the 40 wt.% Al2O3‐containing CPCs showed the optimum CCT of 6498 K (color coordinates: 0.31 and 0.38), as well as a high luminous flux of 1169 lm and efficiency of 166 lm/W at the LD power of 7.05 W. This work has provided a potential idea to optimize the composition uniformity of Al2O3–Ce:YAG CPCs as also to explore their excellent performance in the application of white laser lighting. [ABSTRACT FROM AUTHOR]

(1 − x) BaSrTiO-xMgSnO (BST-xMgSnO, x = 0.5, 1, 3, 5, 7 wt%)ceramics sintered at low temperature were prepared by traditional solid-state reaction method and the effect of MgSnO doped on the microstructure and dielectric property of BST ceramics sintered at low temperature were investigated by X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy. The results showed that the main phase of BST ceramics doped with MgSnO had perovskite structure and a small amount of MgTiO and SrTiO impurity phase. MgSnO doping in BST ceramics sintered at low temperature could shift, pressure and broaden Curie peak remarkably. Dielectric constant (ε) decreased firstly and then increased, dielectric loss (tanδ) decreased firstly and then increased and then decreased, withstand voltage (E) increased firstly and then decreased and then increased when MgSnO doped amount increased. When MgSnO doping amount was 1 wt%, BST ceramics sintered at low temperature had better property with ε of 2,603, tanδ of 0.006, E of 6.3 kV/mm (AC), the sintered temperature was 1,050 °C, the value of △C/C range was 12.5 to −14.8 % in −30 to 85 °C temperature range and the capacitance temperature property was suited for Y5R. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report the facile synthesis of In2O3@In2S3 core–shell nanocubes and their improved photoelectrochemical property. In2O3@In2S3 core–shell nanocubes are grown on a F-doped SnO2 (FTO) glass substrate by a two-step process, which involves the electrodeposition of In2O3 nanocubes and a subsequent ion-exchange treatment. The improved light-harvesting ability and the suitable band alignment of the In2O3@In2S3 core–shell nanocubes generate a remarkable photocurrent density of 6.19 mA cm−2 (at 0 V vs. Ag/AgCl), which is substantially higher than the pristine In2O3 nanocubes. These results provide a new insight into the design of a high-performance photoanode for photoelectrochemical water splitting. [Copyright &y& Elsevier]