Synthesis and characterization of a narrow size distribution of zinc oxide nanoparticles

Zinc oxide nanoparticles (ZnO-NPs) were synthesized via a solvothermal method in triethanolamine (TEA) media. TEA was utilized as a polymer agent to terminate the growth of ZnO-NPs. The ZnO-NPs were characterized by a number of techniques, including X-ray diffraction analysis, transition electron microscopy, and field emission electron microscopy. The ZnO-NPs prepared by the solvothermal process at 150°C for 18 hours exhibited a hexagonal (wurtzite) structure, with a crystalline size of 33 ± 2 nm, and particle size of 48 ± 7 nm. The results confirm that TEA is a suitable polymer agent to prepare homogenous ZnO-NPs

Characterization and X-ray Peak Broadening Analysis in PZT Nanoparticles Prepared by Modified Sol-Gel Method

Lead zirconate titanate nanoparticles (PZT-NPs) were synthesized by a modified sol-gel method and were calcinated at temperatures of 600, 650 and 700 °C. Fourier transform infrared (FTIR), powder X-ray diffraction (XRD) and thermal analysis (TGA/DTA), indicate that single-phase perovskite PZT-NPs are obtained after heat treatment at a temperature of 650 °C. The TEM results obtained from the PZT-NPs confirm that the morphology of the PZT nanoparticles is spherical, with an average diameter size of 17 nm. We also investigated the crystallite development in the nanostructured PZT by X-ray peak broadening analysis. The individual contribution of many small crystallite sizes and lattice strains to the peak broadening in the PZT nanoparticles prepared at different temperatures were studied using Williamson-Hall (W-H) analysis in the range of 2θ = 15-80°. © 2010 Elsevier Ltd and Techna Group S.r.l

XPS and UV\x96vis studies of Ga-doped zinc oxide nanoparticles synthesized by gelatin based sol-gel approach

Undoped and gallium-doped ZnO nanoparticles, (ZnO NPs) (Zn1−xGaxO, x=0.0, 0.03, 0.06, 0.09, 0.12, 0.15), were synthesized by a gelatin-based, sol–gel method. Structural and morphological studies of the resulting products were carried out via X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The XRD results revealed that the sample products were crystalline with a hexagonal wurtzite phase. Furthermore, the TEM images indicated ZnO NPs having approximately spherical shapes, with their particle size distributed over the nanometer range. The XRD and TEM results also showed a decrease in crystallite and particle sizes of NPs from x=0.0 to 0.15. The size-strain plot (SSP) method was employed to study the individual contributions of crystallite sizes and lattice strain to the peak broadening of the undoped and doped ZnO NPs. The effect of doping on the optical band-gap and crystalline quality was also investigated, using ultraviolet-visible (UV–vis), X-ray photoluminescence (XPS), and spectroscopies of the pure and doped ZnO NPs. It was observed that the band-gap and O-vacancies of the doped ZnO NPs were red-shifted in comparison with those of the undoped ZnO NPs in UV–vis and XPS results

X-ray Analysis of ZnO Nanoparticles by Williamson-Hall and Size-Strain Plot Methods

ZnO nanoparticles (ZnO-NPs) were prepared by a sol-gel combustion method from a zinc acetate precursor and acetic acid. The ZnO-NPs were synthesized at calcination temperatures of 650 °C and 750 °C for 1 h. The synthesized ZnO-NPs were characterized by X-ray diffraction analysis (XRD) and TEM. The XRD results revealed that the sample product was crystalline with a hexagonal wurtzite phase. High-magnification transmission electron microscopy (TEM) showed single-crystal ZnO-NPs with nearly spherical shapes. The crystalline development in the ZnO-NPs was investigated by X-ray peak broadening. The Williamson-Hall (W-H) analysis and size-strain plot method were used to study the individual contributions of crystallite sizes and lattice strain on the peak broadening of the ZnO-NPs. The physical parameters such as strain, stress and energy density values were calculated more precisely for all the reflection peaks of XRD corresponding to the wurtzite hexagonal phase of ZnO lying in the range of 20°-100° from the modified form of the W-H plot assuming a uniform deformation model (UDM), uniform stress deformation model (USDM), uniform deformation energy density model (UDEDM) and by the size-strain plot method (SSP). The results obtained showed that the mean particle size of the ZnO-NPs estimated from the TEM, W-H analysis and the SSP method were highly intercorrelated. © 2010 Elsevier Masson SAS. All rights reserved