Comparative studies on CePO 4 and CeO 2 nanoparticles

Abstract : CePO 4 and CeO 2 nanoparticles were successfully synthesized by reflux method for different reflux timings 6 hrs and 12 hrs. Samples were subjected to Powder XRD, FTIR, SEM, UV-Vis, TG/DTA and PL studies. Powder XRD studies reveal that the crystallite sizes of CePO 4 and CeO 2 nanoparticles increases with increasing reflux time. The crystallite sizes of CeO 2 nanoparticles are smaller than CePO 4 nanoparticles which is evident from the peak broadening in XRD analysis. SEM images show that lots of agglomerations in CeO 2 nanoparticles when compared to CePO 4 nanoparticles. UV-Vis spectral studies indicate that the prepared CePO 4 and CeO 2 nanoparticles are highly transparent (~ 94%) in the entire UVVis range. The FTIR analysis confirms the presence of phosphate group in the prepared CePO 4 sample. The peaks corresponding to CeO 2 vibrations are seen in the FTIR spectrum of CeO 2 sample. The Photoluminescence (PL) studies of CeO 2 show two emission peaks around 395 nm and 412 nm, corresponding to violet emission, whereas the PL spectra of CePO 4 shows emission peaks at 487 nm and 547 nm corresponding to bluish green and green emissions. TG/DTA results show that in the case of CeO 2 nanoparticles, the samples prepared at a reflux timing of 6 hrs suffer greater weight loss than the samples prepared at a reflux timing of 12 hrs. But the reflux timing doesn't seem to have any influence on the thermal properties of CePO 4 nanoparticles

Particle Size Effect on the Properties of Cerium Oxide (CeO2) Nanoparticles Synthesized by Hydrothermal Method

International audienceThe Cerium oxide (CeO2) nanoparticles with different particle sizes were successfully synthesized by hydrothermal method with different reaction time. The synthesized CeO2 nanoparticles were characterized by Powder X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Scanning Electron Microscopy (HRSEM), UV-Vis spectroscopy and FTIR spectroscopy. The effects of the particle size on the structural properties of the prepared samples were investigated usingXRD, SEM and HRSEM. The better optical properties exhibited by CeO2 having smaller particle size has been revealed by UV-Visible study. The Photo-catalytic study showed that the lower particle size CeO2 nanoparticles have higher Photo-catalytic activity for degradation of Methylene Blue. The optical properties of CeO2 nanoparticles improve with reduction in the particle siz

Temperature Based Investigation on Structure and Optical Properties of Bi2S3 Nanoflowers by Solvothermal Approach

International audienceA solvothermal process has been employed to synthesis Bi2S3 nanostructures which has a wide spread applications in photodiode, hydrogen storage, high energy batteries, as well as luminescence and catalytic fields. Bismuth nitrate, thiourea and PolyVinyPyrrolidene (PVP), used as the starting materials are dissolved in ethylene glycol for different reaction times. It was found that the temperature plays a key role in determining the shape of the products. The crystalline phase and structure of the Bi2S3 nanostructures were investigated by power X-ray diffraction (XRD). The surface morphology has been analyzed by Scanning electron microscopy (SEM), the optical properties of the Bi2S3 nanoparticles were analyzed using UV-Vis spectroscopy. The functional groups present in the Bi2S3 nanoparticles were characterized by FT-IR spectroscopy. The novel Bi2S3 nanoparticles will be exploited for its application as photocatalyst

Solvothermal synthesis of Bi2S3 nanoparticles and nanorods towards solar cell application

One-dimensional nanostructures have gained more attraction in recent years because of their high aspect ratio. Uniform Bi2S3 nanorods have been grown using N,N-dimethylformamide (DMF) and ethylene glycol (EG) as solvents by solvothermal method, inorder to study the effect of solvent on the properties of the prepared Bi2S3. Also, the reaction temperature has been changed to examine its role in tuning the property of the Bi2S3 nanorods. The x-ray diffraction (XRD) results show that the Bi2S3 nanorods are of orthorhombic phase. The high resolution scanning electron microscope (HRSEM) and high resolution transmission electron microscope (HRTEM) studies reveal the appearance of rod-like structures with the typical length in the range of 1 µm and average diameter is around 150 nm. The solvent effects and reaction temperatures are discussed in detailed. The band gap of the prepared samples have been estimated using Tauc plot and this suggests that the prepared Bi2S3 nanostructures may find potential applications in the fabrication of solar cells.Accepted versio

Comparative Study of Properties of L-Histidine and L-Histidine Nickel Nitrate Hexahydrate Crystals Grown by Slow Evaporation

International audienceL-Histidine (LH) is an amino acid. It is an organic material. L-Histidine Nickel Nitrate Hexahydrate (LHNNH) is a semi organic material. It is a complex of bivalent nickel ion with L-Histidine amino acid. Complexes of bivalent metal ions with amino acids are generally good NLO materials. Crystals of L-Histidine and L-Histidine Nickel Nitrate Hexahydrate (LHNNH) have been successfully grown by slow evaporation method using water as solvent. The crystal structure and lattice parameters of LH and LHNNH are determined by Single crystal X-ray diffraction analysis. The functional groups in LH and LHNNH are confirmed by FTIR analysis. With the help of UV-Vis spectroscopy the optical band gap and optical transparency are studied. The chemical composition of LH and LHNNH are studied by CHN and EDAX analysis. Thermally stability and thermal phase transitions of LH and LHNNH are analyzed by TGA/DTA. The Second Harmonic Generation (SHG) efficiency of LH and LHNNH have been experimentally estimated. Introduction: L-Histidine is an optically active α-amino acid and is a tridentate ligand that has an imidazole ring, amino and carboxylate groups. Amino acids are the potential candidates for optical second harmonic generation because they contain chiral carbon atom and crystallize in non-centro symmetric space groups and it is an essential criterion for nonlinear application [1]. Amino acids are interesting materials for NLO applications. Complexes of amino acids with inorganic salts are promising materials for optical Second Harmonic Generation. In recent years semi organic crystals have emerged as extremely promising building blocks for NLO materials. They share the properties of both organic and inorganic materials. Amino acids are interesting materials for NLO applications, as they exhibit molecular chirality, absence of strongly conjugated bonds and zwitterionic nature of the molecule [2]

Surfactant assisted synthesis of nickel vanadium oxide nanostructures with strong visible-light-induced photocatalytic activity

Nickel vanadium oxide (NiV2O6) nanoparticles were effectively synthesized using hydrothermal technique by changing the surfactants. The variation in the properties of the NiV2O6 based on the surfactants like cetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG) and Thio-glycolic acid (T-GA) was studied and reported. Methylene blue (MB) dye was utilized to investigate the photocatalytic activity of nickel vanadium oxide nanoparticles generated under the presence of CTAB as surfactant. The materials showed more than 80% degradation of methylene blue dye in 150 min. A putative photocatalytic process has been postulated in this paper. Nanoparticles were shown to have high photocatalytic activity and stability, according to the findings. Based on radical trapping experimental observations conducted with different scavengers such as 2-propanol, benzoquinone and EDTA, the major role played by OH−in the degradation process were reported in detail