Yue-Hong Huang

ZnFe2O4 nanoparticles: microwave-hydrothermal ionic liquid synthesis and photocatalytic property over phenol.

We report the microwave-hydrothermal ionic liquid (MHIL) synthesis and photocatalytic property over phenol of ZnFe(2)O(4) nanoparticles. Zn(CH(3)COO)(2).2H(2)O and Fe(NO(3))(3).9H(2)O were used as the zinc and iron sources, respectively, in the presence of CO(NH(2))(2) and the ionic liquid 1-n-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM][BF(4)]). Deionized water was used as a solvent. The ionic liquid [BMIM][BF(4)] and microwave heating temperature have significant influences on the crystal phase of the product. Different dosages of [BMIM][BF(4)] or microwave heating temperature could lead to the formation of different products such as ZnFe(2)O(4) and beta-FeOOH. The MHIL method has the advantages such as simplicity, rapidness and energy saving. The ZnFe(2)O(4) nanoparticles prepared by the MHIL method exhibit high photocatalytic activity for the degradation of phenol, which was up to 73% within 360 min. The TOC measurement confirmed the good photocatalytic efficiency of ZnFe(2)O(4) nanoparticles.

Sonochemical synthesis of single-crystalline CeOHCO3 rods and their thermal conversion to CeO2 rods

Single-crystalline CeOHCO3 rods with an orthorhombic structure have been successfully synthesized by the sonochemical method from aqueous solution containing CeCl3 and urea. Polycrystalline CeO2 rods have been prepared by thermal conversion of single-crystalline CeOHCO3 rods at 500 °C in air. CeOHCO3 and CeO2 rods were characterized by x-ray powder diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TG) and differential scanning calorimetric analysis (DSC).

Structure, thermal and optical properties of Ca9Y0·5La0·5(VO4)7 – potential nonlinear optical material

Abstract The structure of a new nonlinear optical crystal, Ca9Y0·5La0·5(VO4)7, was solved, for first time to our knowledge. It belongs to trigonal system with space group R3c, its unit-cell parameters are: a = 10·8717(2) Å, c = 38·0753(14) Å, V = 3897·34(18) Å3, Z = 6, dc = 6·3279 g cm−3. The thermal expansion, the special heat capacity and the thermal conductivity of the crystal were investigated in detail. The crystal’s relative intensity for second harmonic generation is about 1·8 times as large as that of KH2PO4. Its transmittance exceeds 70% in the range of 400–2700 nm. From the measured principal refractive indices, the Sellmeier equations were derived. The results show that Ca9Y0·5La0·5(VO4)7 is expected to be a promising new frequency-doubling laser crystal.

Growth and spectral characteristics of KYb(WO4)(2) crystal

Abstract The present paper reports the growth and spectroscopic properties of KYb(WO4)2 crystal. The KYb(WO4)2 crystal with dimensions of 32 × 29 × 12 mm was grown from a mixed flux of K2WO4 and KF by the TSSG method. The spectroscopic properties of KYb(WO4)2 crystals were investigated. The absorption and emission cross-sections of KYb(WO4)2 crystal are 4˙32 × 10–20 cm2 at 981 nm and 3˙69 × 10–20 cm2 at 1024 nm for E//X polarisation respectively. The laser parameters of KYb(WO4)2 crystal were evaluated. These results suggest KYb(WO4)2 crystal as a potential candidate for microchip laser medium.

Microwave-assisted preparation of Ca{sub 6}Si{sub 6}O{sub 17}(OH){sub 2} and {beta}-CaSiO{sub 3} nanobelts

Xonotlite (Ca6Si6O17(OH)2) nanobelts were synthesized by a microwave-assisted hydrothermal method at 180 8C for 90 min independent of the feeding molar ratio of Ca(NO3)24H2 Ot o Na 2SiO39H2O in the range of 0.8–3.0. Crystalline wollastonite (b-CaSiO3) nanobelts were obtained by microwave thermal transformation of Ca6Si6O17(OH)2 nanobelts at 800 8C for 2 h. Ca6Si6O17(OH)2 nanobelts were used as both the precursor and the template for the preparation of b-CaSiO3 nanobelts. The morphology and size of Ca6Si6O17(OH)2 nanobelts could be well preserved during the microwave thermal transformation process. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED).Xonotlite (Ca{sub 6}Si{sub 6}O{sub 17}(OH){sub 2}) nanobelts were synthesized by a microwave-assisted hydrothermal method at 180 {sup o}C for 90 min independent of the feeding molar ratio of Ca(NO{sub 3}){sub 2}.4H{sub 2}O to Na{sub 2}SiO{sub 3}.9H{sub 2}O in the range of 0.8-3.0. Crystalline wollastonite ({beta}-CaSiO{sub 3}) nanobelts were obtained by microwave thermal transformation of Ca{sub 6}Si{sub 6}O{sub 17}(OH){sub 2} nanobelts at 800 {sup o}C for 2 h. Ca{sub 6}Si{sub 6}O{sub 17}(OH){sub 2} nanobelts were used as both the precursor and the template for the preparation of {beta}-CaSiO{sub 3} nanobelts. The morphology and size of Ca{sub 6}Si{sub 6}O{sub 17}(OH){sub 2} nanobelts could be well preserved during the microwave thermal transformation process. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED).