Microwave plasma synthesis of nano‐crystalline YSZ

Abstract

Nanocrystalline yttria‐stabilized zirconia (YSZ) powder and compacts have been successfully synthesized by microwave plasma synthesis co‐evaporating Y and Zr precursors from a single source. Both liquid and solid mixtures of chemically homologous precursors were tested. Electron micrographs and X‐ray diffraction studies reveal small crystallites in the range 3–4 nm with a narrow size distribution. Crystallite sizes smaller than 25 nm are preserved even after subsequent annealing at temperatures up to 950 °C. A comparison with other gas‐phase synthesis routes of nanocrystalline YSZ is given. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

In‐situ dispersion of ZrO2 nano‐particles coated with pentacene

“…Uncoated n-ZrO 2 shows broad diffraction lines, from which a small mean crystallite size in the range of 3-5 nm and a cubic or tetragonal lattice structure is deduced [10,12], similarly as observed in both XRD and transmission electron microscopy (TEM) studies on Y-doped ZrO 2 synthesised under similar processing conditions [9]. X-ray diffractograms of pentacene coated n-ZrO 2 show a high diffuse background and a weaker signature of crystalline ZrO 2 .…”

“…Based on previous results [9] Zr(IV)butoxide (supplied by ABCR Chemicals, Karlsruhe) was used as a precursor for synthesising the n-ZrO 2 core particles. The oxide particles formed in the plasma zone were subsequently exposed downstream to pentacene (Sigma Aldrich) vapour from a second evaporation source leading to coating ( Fig.…”

Structural and optical properties of nanoparticulate Y2O3:Eu2O3

“…The nanoparticulate Y 2 O 3 :Eu 2 O 3 was produced by co-evaporation of the chemically homologous tetramethylheptanedionate Y(TMHD) 3 and Eu(TMHD) 3 precursors in an Arstream at about 180 • C. The precursor vapor was mixed with a reaction gas of 20% oxygen in argon and then decom-posed in the microwave induced plasma (2.45 GHz, 500 W) under similar conditions as described for the synthesis of YSZ [9]. Electric charging induced by the plasma together with low reaction temperatures prevents the formation of hard agglomerates.…”

“…The present work aims at synthesizing and studying the structural and luminescence properties of such Y 2 O 3 :Eu 2 O 3 nanoparticles with a small initial particle size. For this goal, microwave plasma (MWP) synthesis provides an ideal fabrication route [9]. The low reaction temperature of about 400 • C and the electric charging in the nonequilibrium plasma leads to the formation of nanoparticles with both a small mean size of d ∼4-5 nm and a narrow size distribution.…”

Biosynthesis of Zirconium dioxide nanoparticles by Streptomyces sp. HC1: Characterization and Bioactivity

“…In recent years, different physical and chemical syntheses have been used for zirconium nanoparticles. Hydrothermal techniques, thermal decomposition, microwave plasma, sol-gel methods and laser ablation are among the newly developed techniques [25][26][27][28][29]. Zirconium (IV) alkoxides used in sol-gel method to synthesize zirconium dioxide nanoparticles cause high toxicity and high cost, making it difficult to control the homogeneity of different components [30].…”