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0–4 wt% (0–4.11 mol%) Ce-doped MoO3 nanobelts were successfully synthesized by hydrothermal method at 180 °C for 20 h. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show orthorhombic MoO3 and Ce-doped MoO3 nanobelts with >10 μm long, 200–250 nm wide and their growth along the [010] direction. The photocatalytic performance of pure MoO3 and Ce-doped MoO3 nanobelts was investigated through photodegradation of methylene blue (MB) under visible radiation. In this research, 3 wt% (3.08 mol%) Ce-doped MoO3 nanobelts show the highest photocatalytic performance of 94.84% for degradation of MB induced by xenon visible radiation within 50 min.

Heterostructure Ag3PO4/Bi2WO6 nanocomposites were synthesized by precipitation-deposition method. X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and UV-visible spectrophotometry revealed that cubic Ag3PO4 nanospheres with

Cl-doped Bi 2 MoO 6 as visible light driven photocatalyst was synthesized by a hydrothermal method. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). In this research, the Cl-doped Bi 2 MoO 6 samples have high crystalline orthorhombic Bi 2 MoO 6 phase. The 3 wt% Cl-doped Bi 2 MoO 6 showed excellent photocatalytic degradation of rhodamine B and followed the first order kinetics model under visible light irradiation.

In this study, various sizes and chemical compositions of Au/Pd nanoparticles with core/shell structure were successfully prepared by employing a simple successive reduction method without addition of any stabilizer. The optical properties, morphologies, chemical compositions and crystal structures of the synthesized particles were fully characterized by using a combination of UV–vis spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, wavelength-dispersive X-ray spectroscopy, selected area electron diffraction and X-ray diffraction techniques. The catalytic activities of the synthesized Au/Pd nanoparticles for 4-nitrophenol reduction were also investigated and compared with monoatomic Au and Pd nanoparticles. The highest catalytic activity of bimetallic was obtained from AuPd 4 nanoparticles. With comparable size, Au/Pd nanoparticles provide better catalytic activity than those of monometallic Au and Pd. However, lower catalytic activities of Au/Pd nanoparticles are shown compared with that of smaller-size Au nanoparticles. This study also reveals that the size effect of catalysts plays important role on catalytic activity more than only changing their chemical constituents.

ZnO nanoplates were successfully synthesized by hydrothermal method in the solutions containing CTAB. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). In this research, the as-synthesized samples were hexagonal wurtzite ZnO structure without any impurities and were composed of hexagonal ZnO nanoplates with the vibration mode of Zn–O bonds. The photocatalytic activity of hexagonal ZnO nanoplates showed superior photodegradation of methylene blue (MB) of 94.15 % under UV light irradiation within 80 min. The degradation efficiency of reused hexagonal ZnO nanoplates as photocatalyst indicated that ZnO nanoplates are very stable and reusable under UV light illumination.

CeVO4 nanostructures were successfully synthesized by polyethylene glycol-assisted hydrothermal process. The products synthesized in the solutions containing 0.000–0.020 g polyethylene glycol (PEG) were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). For the use of 0.015 and 0.020 g PEG, the products were uniform and pure tetragonal CeVO4 nanorods growing along the [001] direction. The stretching and bending modes of VO 4 3 - tetrahedrons were detected by Fourier transform infrared (FTIR) and Raman spectroscopy. Methylene blue was used as a representative dye pollutant for evaluating photocatalytic activity under UV radiation. In this research, CeVO4 nanorods synthesized in the solution containing 0.015 g PEG showed the highest photodegradation of 98.03% and the highest apparent rate constant of 0.0128 min−1 within 300 min.

Copper ferrite (CuFe2O4) nanoparticles were prepared in alkaline solutions containing Cu(NO3)2·6H2O and Fe(NO3)3·9H2O with the pH of 6–12 by microwave-hydrothermal method. The as-prepared products characterized by XRD were specified as cubic CuFe2O4 phase. Average sizes of the CuFe2O4 nanoparticles calculated by Scherrer formula are in the same range as those obtained by TEM analysis. FTIR shows main transmittance band at 585 cm−1, corresponding to stretching mode of tetrahedral complexes. Saturation magnetization, remanence and coercivity were increased with increasing in the particle-size and crystalline degree of the nanoparticles.

Cubic and star-shaped dendritic PbS structures were successfully synthesized by the 120 °C and 10 h solvothermal reactions of lead nitrate and sulfur sources (thiourea and thiosemicarbazide). XRD, SEM and TEM analyses revealed the presence of pure cubic PbS phase with different morphologies, controlled by the sulfur sources. Cubic and star-shaped dendritic PbS crystals were respectively synthesized in the solutions containing thiourea and thiosemicarbazide as sulfur sources. Possible formation mechanisms of cubic and star-shaped dendritic PbS structures were also proposed.

Highly crystalline CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 nanoparticles were successfully synthesized by the co-precipitation of mixtures of Ca(NO 3 ) 2 4H 2 O or Sr(NO 3 ) 2 , and Na 2 MoO 4 2H 2 O or Na 2 WO 4 2H 2 O dissolved in ethylene glycol at room temperature (30 °C). Phases, morphologies, atomic vibrations and optical properties were analyzed by X-ray diffraction, transmission electron microscopy, Fourier transform infrared and Raman spectrophotometry, and ultraviolet–visible and photoluminescent spectroscopy. All products were proved to be MXO 4 (M = Ca and Sr, and X = Mo and W) with body-centered tetragonal scheelite structures, having round nanoparticles with the average sizes of 12.06 ± 1.65, 16.40 ± 2.44, 15.49 ± 2.19, and 15.40 ± 2.30 nm for CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 , respectively. Their ν 1 (A g ), ν 3 (B g ), ν 3 (E g ), ν 4 (B g ), ν 2 (A g ) and ν f.r. (A g ) vibration modes were also detected – being shifted to lower wavenumbers from MMoO 4 to MWO 4 , due to the change of efficient atomic mass of the oscillating ions between X 6+ and O 2− in the [XO 4 ] 2− complexes. Band gaps of CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 were determined to be 5.07, 3.72, 5.40, and 4.47 eV, respectively. Photoluminescent (PL) emissions were at 414, 413, 418, and 414 nm for CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 , respectively.

In Thailand, the hairy maggots of the blow flies, Chrysomya rufifacies (Macquart) and Chrysomya villeneuvi Patton, are of forensic importance. Both flies are closely related species, not only in the morphological appearance of their larvae and puparia, but also on the aggressive feeding habit of the former. In our continuing studies of forensically important flies, identification of immature ones needs particular attention. In this study, we reported the morphological comparison between the puparia of these two blow fly species using scanning electron microscopy (SEM). Observation revealed that the cuticular sculpture of tubercles along the dorsal and lateral segments had markedly different features: with C. rufifacies having many sharp spines assembling only at the tip, while of C. villeneuvi bore stout spines throughout the tubercle. A larger number of globules at the bubble membrane on the dorsolateral border of the fifth segment was found in C. villeneuvi (average 225) than in C. rufifacies (average 35), and more papillae was observed on the anterior spiracle in C. villeneuvi (13-15) than in C. rufifacies (9-12). However, the morphology of distinct net-like patches of the integument and structure of the posterior spiracle of both species were almost identical. Morphological comparison in this study permitted identification of the puparia of both fly species, particularly in areas where they co-exist.