Phase transitions and slow spin dynamics of slightly inverted A-site spinel CoAlGaO.

We report the properties of an A-site spinel magnet, CoAlGaO, and analyze its anomalous, low-temperature magnetic behavior, which is derived from inherent, magnetically frustrated interactions. Rietveld analysis of the x-ray diffraction profile for CoAlGaOrevealed that the metallic ions were randomly distributed in the tetrahedral (A-) and octahedral (B-) sites in the cubic spinel structure. The inversion parametercould be controlled by varying the gallium (Ga) composition in the range 0.

Research progress on surface modifications for phosphors used in light-emitting diodes (LEDs).

Stable and efficient phosphors are highly important for light-emitting diodes (LEDs) with respect to their application in solid-state lighting, instead of conventional lamps for general lighting. However, some problems, like low stability, low photoluminescence (PL) efficiency, and serious thermal degradation, are commonly encountered in phosphors, limiting their applications in LEDs. Surface modifications for some phosphors commonly used in LED lighting, including fluoride, sulphide, silicate, oxide, nitride, and oxynitride phosphors, are presented in this review.

Preparation of Oriented ZnO Rod Arrays Using Hexagonal Plate-Like Particles as a Seed Layer.

ZnO rod film is a promising material for electrodes and sensors due to its large surface area and high electrical conductivity. One of the drawbacks of conventional ZnO rod film is the random orientation of rods. In this study, an oriented ZnO seed layer composed of hexagonal plate-like ZnO particles was prepared by dip-coating.