Nuengruethai Ekthammathat

Hydrothermal synthesis and characterization of Bi 2 MoO 6 nanoplates and their photocatalytic activities

The pH effect of the precursor solutions on the phase, morphologies, and photocatalytic activity of Bi2MoO6 synthesized by a hydrothermal reaction at 180°C for 20 h was investigated. X-ray powder diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) revealed the presence of pure orthorhombic well-crystallized γ-Bi2MoO6 nanoplates, including the symmetric (A1g) and asymmetric (A2u) stretching vibrations of the MoO6 octahedrons involving the motion of apical oxygen atoms. The photocatalytic activity of Bi2MoO6 nanoplates at the pH 6 determined via the decomposition of rhodamine-B (RhB) organic dye was the highest at 98.66% decolorization under Xe light irradiation.

Microwave-assisted synthesis and characterisation of uniform LaPO4 nanorods

Lanthanum phosphate (LaPO4) phosphor materials with one-dimensional (1D) nanorods and nanoparticles were successfully synthesised from LaCl3 · 7H2O and Na3PO4 · 12H2O with pH adjusted at the range 1–6 using 37% HNO3 by the microwave radiation at 180 W for 60 min. X-ray diffraction patterns indicated that the as-synthesised products were hexagonal LaPO4 nanostructures. Scanning electron microscopy and transmission electron microscopy analyses showed that these products were nanoparticles, short and long nanorods, controlled by pH of the precursor solutions. Asymmetric stretching and bending vibrations of the groups were detected using Fourier transform-infrared spectroscopy. A possible formation mechanism of LaPO4 phosphor materials with 1D nanorods and nanoparticles was also proposed according to the experimental results.

Synthesis and characterization of CeVO 4 by microwave radiation method and its photocatalytic activity

A general microwave synthesis method was developed to synthesize cerium orthovanadate (CeVO4) nanostructures without the use of any catalysts or templates. This method is able to control the shape and size of the products by adjusting the pH of precursor solutions to be 1-10. Phase, purity, and different morphologies of the products were characterized by XRD, FTIR, SEM, and TEM. They showed that the as-synthesized products exhibited pure single crystalline CeVO4 with tetragonal structure. Their morphologies developed in sequence as nanoparticles (pH = 4-10), nanorods (pH = 2, 3), and microflowers (pH = 1). UVvisible spectra were used to estimate the direct energy gaps of CeVO4 nanorods and microflowers: 3.77 and 3.65 eV, respectively. Photoluminescence (PL) of CeVO4 microflowers showed strong emission intensities at 578 nm. These results were in the range of possible application for photocatalysis, investigated by studying the degradation of methylene blue.

Hydrothermal synthesis, characterization, and visible light-driven photocatalytic properties of Bi 2 WO 6 nanoplates

In this research, the effects on reaction temperature and length of time on Bi2WO6 nanoplates by hydrothermal synthesis on morphologies and photocatalytic properties were studied. The products obtained at different reaction temperature and reaction time were characterized by XRD, Raman, FTIR, SEM, and TEM techniques. The photocatalytic properties of the samples were measured by decomposing the rhodamine-B organic dye. XRD pattern was specified as pure orthorhombic well-crystallized Bi2WO6 phase for the 180°C and 20 h synthesis. Its FTIR spectrum shows main absorption bands at 400-1000 cm-1, assigned to Bi-O stretching, WO stretching, and W-O-W bridging stretching modes. SEM and TEM analyses show that the product was composed of nanoplates. Photocatalytic activity of Bi2WO6 nanoplates shows the 98.24% degradation of rhodamine-B under the Xe light irradiation within 100 min.

Facile hydrothermal synthesis and optical properties of monoclinic CePO 4 nanowires with high aspect ratio

One-dimensional cerium phosphate (CePO4) nanowires (NWs) were successfully synthesized by a facile and simple hydrothermal method at 200°C for 12 h, using Ce(NO3)3ċ6H2O and Na3PO4ċ12H2O as starting materials, and followed by pH adjusting to be 1-3 using HNO3 (conc.). Phase, morphologies, and vibrationmodes of the as-synthesized CePO4 products, characterized by XRD, SEM, TEM, and FTIR, were proved to be perfect and uniformmonoclinic CePO4 nanowires with aspect ratio of more than 250 for the product synthesized in the solution with the pH of 1. The UV-visible and photoluminescence (PL) spectrometers were used to investigate optical properties of the as-synthesized monoclinic CePO4 nanowires.

Hydrothermal Synthesis, Characterization, and Optical Properties of Ce Doped Bi2MoO6 Nanoplates

Undoped and Ce doped Bi2MoO6 samples were synthesized by hydrothermal reaction at 180°C for 20 h. Phase, morphology, atomic vibration, and optical properties were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6 nanoplates with the growth direction along the [0b0], including the asymmetric and symmetric stretching and bending modes of Bi–O and Mo–O. Undoped and Ce doped Bi2MoO6 samples show a strong absorption in the UV region.

Hydrothermal synthesis, structure, and optical properties of pure and silver-doped Bi2MoO6 nanoplates

The effect of Ag doping on Bi2MoO6 was studied in this research. Ag-doped Bi2MoO6 nanoplates were synthesized by a hydrothermal method at 180°C for 20 h. X-ray powder diffraction (XRD) and selected area electron diffraction (SAED) confirm that the products have orthorhombic Bi2MoO6 structure. Bi2MoO6 nanoplates were detected by transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) shows peaks with binding energies of 368.84 and 374.87 eV which could be attributed to Ag 3d5/2 and Ag 3d3/2, confirming that Ag is present in the Bi2MoO6 matrix. Raman and FTIR spectra show the vibration of asymmetric and symmetric stretching and bending modes of MoO6 octahedrons. The optical properties of products were characterized by UV–Vis spectroscopy. They show strong absorption in UV–Vis region.

Hydrothermal synthesis, characterization, and optical properties of Ce doped Bi 2 MoO 6 nanoplates

Undoped and Ce doped Bi2MoO6 samples were synthesized by hydrothermal reaction at 180°C for 20 h. Phase, morphology, atomic vibration, and optical properties were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6 nanoplates with the growth direction along the [0b0], including the asymmetric and symmetric stretching and bending modes of Bi–O and Mo–O. Undoped and Ce doped Bi2MoO6 samples show a strong absorption in the UV region.

Hydrothermal Synthesis and Characterization of Ho Doped Bi2MoO6 Nanoplates and their Optical Properties

0–3 % Ho doped Bi2MoO6 samples were synthesized by hydrothermal reaction at 180 °C for 20 h. Their phase, morphologies, atomic vibration and optical properties were characterized by X-ray powder diffraction (XRD), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6 nanoplates with asymmetric and symmetric stretching and bending modes of MoO6 octahedrons, and their strong absorption in the UV visible region.

Synthesis, Characterization and Antibacterial Activity of BiVO 4 Microstructure

Hyperbranched BiVO4 microstructure were successfully synthesized by a hydrothermal method. Upon characterization the products by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, selected area electron diffraction (SAED) and photoluminescence (PL) spectroscopy, pure monoclinic hyperbranched BiVO4 with dominant vibration peak at 810 cm–1 and strong photoemission peak at 360 nm was synthesized in the solution with pH 1. In the solution with pH 2, tetragonal BiVO4 phase was also detected. In this research, antibacterial activity against S. aureus and E. coli was investigated by counting the colony forming unit (CFU). At 37°C within 24 h, the monoclinic BiVO4 phase can play the role in inhibiting S. aureus growth (350 CFU/mL remaining bacteria) better than that against E. coli (a large number of remaining bacteria).