Phase Purity Of Nanoparticles Research Articles

Synthesis, characterization and gas sensing properties of the rhombohedral ilmenite CdSnO3 nanoparticles

Herein, we report the synthesis of rhombohedral ilmenite CdSnO3 nanoparticles through coprecipitation method. The effect of sintering temperatures on phase purity of nanoparticles was observed from X-ray diffraction (XRD) analysis and further their structure parametres were determined. XRD patterns confirmed the formation of stable and phase pure rhombohedral ilmenite crystal structure of nanoparticles calcinated at 900 °C. For the first time, experimental observation of theoretically calculated various Raman active modes corresponding to CdSnO3 samples has been reported. The electron microscopy results suggest that synthesized nanoparticles have spherical shape with diameter lying in the range of 40–45 nm which is in accordance with the crystallite size as calculated using XRD data. The gas sensors were fabricated to explore the sensing properties of synthesized nanoparticles at different operating temperature. The sensing results shows that the sensor have good selectivity for propanol against the other gases at relatively lower temperature of 150 °C.

Facile synthesis of CuFe2O4 doped polyacrylic acid hydrogel nanocomposite and its application in dye degradation

Polyacrylic acid hydrogel doped with copper ferrite nanoparticles has been prepared and studied for the removal and degradation of organic dye (methylene blue) from wastewater. Phase purity of nanoparticles was confirmed by powder X-ray diffraction and EDX analysis. Raman spectra showed three bands at Eg, F2g and A1g, attributing the formation of spinel phase with a band gap of 2.12 eV. Hydrogel composite showed an increase in weight by 1771% when soaked in water. Degradation and absorption studies of methylene blue dye solution with copper ferrite nanoparticles as well as hydrogel nanocomposite suggest absorption of dye by hydrogel and degradation with copper ferrite nanoparticles. Such hydrogel nanocomposites could be a promising material for mitigation of water pollution caused by organic dyes discharged by small and medium scale industries.

Synthesis and Development of Thermoelectric Properties in Layered Bi2A2CoO6

Bi-based layered cobalt oxide [Bi2 A 2CoO6] with A = (Ca2+, Mg2+) nanoparticles were prepared by co-precipitation method. Coprecipitation method was used to improve homogeneity and phase purity of nanoparticles and is rarely reported for such type of materials. From X-ray diffraction (XRD) data, structural analysis was carried out for both samples Bi2Ca2CoO6 (BCCO) and Bi2Mg2CoO6 (BMCO). Crystallite size, lattice constants, and volume of unit cell were calculated using XRD data. Both compositions showed monoclinic crystal structure with space group C2/c. Crystallite sizes obtained were 52 and 50 nm for BCCO and BMCO samples, respectively. Scanning electron micrographs show the particle-like morphology with an average particle size of 54 and 68 nm for BCCO and BMCO samples, respectively. Thermogravimetric analysis-(TGA)-differential scanning calorimetery (DSC) technique was used to observe role of heat changes in both the samples with temperature variation up to 1000∘C. BCCO was found thermally more stable as compared to BMCO. Electrical resistivity decreased with increase in temperature, and BMCO showed high values as compared to BCCO. Thermal transport properties like thermal conductivity, thermal diffusivity, and volumetric heat capacity were determined. Both compositions are low thermally conducting materials. BCCO sample showed higher thermal conduction as compared to BMCO. BCCO sample could be a better candidate as thermoelectric material as compared to BMCO.

Solvothermal synthesis and analysis of Bi1−xSbx nanoparticles

Abstract Bismuth–antimony alloy nanoparticles have been synthesized by a facile solvothermal method using N,N-dimethylformamide and ethylene glycol as solvent/reducing agent; BiCl 3 , SbCl 3 and Bi(NO 3 ) 3 as precursors; and citric acid as a surface modifier/stabilizing agent. The particle size and size distribution of Bi nanoparticles were analyzed as a function of the synthesis conditions: molar ratio of precursor to surfactant, precursor concentration and reducing agent. Synthesis of Sb and Bi 0.88 Sb 0.12 under similar conditions was also investigated. The phase purity of nanoparticles was confirmed from X-ray diffraction and thermogravimetry and the nanoparticle morphology was investigated by transmission electron microscopy. A case study of Bi nanoparticles with detailed analysis of the particle morphology and size distribution of the nanoparticles is reported.