Emanation thermal analysis study of the preparation of ruthenia-titania-based finely dispersed powders.
Emanation thermal analysis (ETA), thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffraction analysis (XRD), and transmission electron microscopy (TEM) were used for the characterization of thermal behavior of hydrous oxides (RuO(2))(x)-(TiO(2))(1-x).nH(2)O and dehydrated oxides (RuO(2)) (x)-(TiO(2))(1-x), respectively (x=1, 0.9, and 0.7) on heating in argon and argon +10% hydrogen, respectively. The samples were heated in the range 20-600 degrees C at the constant heating rate 6 K/min. From the TG and DTA results the temperature intervals of dehydration and/or reduction of ruthenium dioxide into Ru metal were determined. ETA (based on the measurement of radon previously incorporated into the sample) brought about the information about surface area development and microstructure changes in the near surface layers up to 80 nm under in situ conditions of the heating. The temperature intervals of the annealing of near surface and structure defects serving as diffusion paths for radon were determined from the ETA results.
Balek
V
V
Nuclear Research Institute, Rez, CZ-250 68, Czech Republic.
Mitsuhashi
T
T
Zelenák
V
V
Vecerníková
E
E
Subrt
J
J
Haneda
H
H
Bezdicka
P
P
D001128:Argon / Q000737:chemistry; D004055:Differential Thermal Analysis / Q000379:methods*; D006859:Hydrogen / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D011886:Radon / Q000032:analysis; D017975:Ruthenium Compounds / Q000737:chemistry*; D013696:Temperature; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
D017975:Ruthenium Compounds; C029017:ruthenium dioxide; C009495:titanium dioxide; D001128:Argon; D006859:Hydrogen; D014025:Titanium; D011886:Radon