Microstructural Analysis of Boehmite Nanoparticles Prepared by Rapid Hydrolysis of Aluminum Sec-butoxide

Abstract

Abstract. Microstructural properties of six samples, prepared by rapid hydrolysis of aluminum secbutoxide, were investigated at RT using field emission scanning electron microscopy (FE SEM), X-ray powder diffraction (XRD) and Fourier transform infrared (FT-IR) spectrometry. The results of structural analysis show that, regardless of a significant difference in the processing parameters (pH, temperature, time of synthesis), all products contain boehmite as the only crystal phase present. The results of FE-SEM analysis indicate a significant difference in the morphology of obtained boehmites (plates, needles, granules). The results of line-broadening analysis of powder diffraction patterns (Le Bail method -program GSAS) indicate the presence of very small anisotropic crystal domains (around 1.5 to 7 nm in the direction 010; around 3 to 16 nm in the direction perpendicular to 010). In all cases the parameters that contribute to the strain broadening of diffraction lines decrease to nearly zero, which suggests that the obtained boehmites are almost strain-free. (doi: 10.5562/cca1884)

Bioinspired Synthesis of Lepidocrocite‐Containing Material and Its Catalytic Behaviour in CO Oxidation

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Structural, Morphological and Optical Properties of Nanoproducts of Zirconium Target Laser Ablation in Water and Aqueous SDS Solutions

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“…Average size of particles for both parts of dioxide and metal zirconium reduces to 40-45 nm. The reduction of crystallite average sizes at M = 0.01 and 0.05 with regards to crystallite sizes at M = 0 is caused by the influence of surfactant -SDS, which restricts nanoparticles growth [29,30] [ 28]. At the concentration of SDS in solution up to M = 0.1 XRD patterns is observed as a spectrum of well crystallized SDS, a considerable part of which is oriented along the surface of glass plate (plane 00L), a smaller part is distributed chaotically (Fig.…”

Cluster-assembled cubic zirconia films with tunable and stable nanoscale morphology against thermal annealing

“…26 Recently, it has been shown that nanocrystalline t-ZrO 2 can be truly thermodynamically more stable than m-ZrO 2 in air below 1200 C in the absence of coarsening, 27 offering further support to the thermodynamic surface energy hypothesis.…”