Reactions of antimony-doped SnO2 powder with molten glass in resistive composite formation

Conclusions Heat treatment of (Sn-Sb-0)-glass composites causes antimony and tin to diffuse into the glass. Around the particles, the glass acquires a diffusion profile. The diffusion coefficients of those ions at 1173 K are, respectively, 10^–15 and 10^–16 m²/sec.Translated from Poroshkovaya Metallurgiya, No. 11, pp. 28–32, November, 1990.     

Electrical conductivity of composite thick films based on powders of doped tin dioxide

Conclusions The electrical conductivity mechanism of doped tin dioxide composite films, which determines their resistivity temperature dependence, is connected with carrier transfer across thin interlayers of a glass phase and has small activation energies characteristic of jump or tunnel conductivity.Translated from Poroshkovaya Metallurgiya, No. 12(264), pp. 65–69, December, 1984.     

Effect of heat treatment on the dispersity of Sn(IV)—Sb—O powders and the porosity of thick-film gas sensors based on them

A study is made of how the granulometric composition and porosity of powders of solid solutions in the system Sn(IV)−Sb−O is affected by the conditions of precipitation of mixtures of tin hydroxide and antimony hydroxide and the heat-treatment temperature. Powders of tin and antimony hydroxides have a microporous structure and a high (≥200 m ²/g) specific surface. Heat treatment above 870 K forms Sn_1−xSb_xO₂ solid solutions, this being accompanied by an increase in the size of the particles and transformation of the microporous structure to a mesoporous structure. An increase in the antimony content of the solid solutions helps form finer powders. A examination is made of the parameters of the pore structure of bulk specimens of semiconductor gas sensors obtained by heat-treating mixtures of powders of solid solutions and ultrafine clay. Institute for Problems of Materials Science, Ukraine National Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 5–6(407), pp. 111–116, May–June, 1999.     

Structure formation of thin-film resistance composites based on alloyed tin dioxide

The nature of interaction between tin dioxide and some refractory borides during heat treatment of resistive composites in air is studied by differential thermal analysis and x-ray diffraction. The reaction products are β-Sn, metals and boron oxides. Addition of HfB₂, ZrB₂, and LaB₆ to composites based on Sb-doped tin oxide result in a reduction of the film temperature coefficient of resistance. Materials Science Institute, Ukrainian Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 5-6, pp. 105–110, May–June, 1998.     

Surface properties of Sn(IV)-Sb-O powders and sensor materials based on them

X-ray photoelectron spectroscopy and electron Auger spectroscopy have shown that the surfaces are covered by Sb³⁺ ions and have oxygen vacancies in powders of solid solutions in the Sn_1?x-Sb_xO₂ system kept under the conditions of nonequilibrium synthesis, and the same applies to thick-film sensor materials based on them. These surface defects act as centers that provide sensitivity to gases and provide a basis for materials promising for use in gas sensor electronics.     

Electrical properties of ruthenium dioxide base thick films with additions of high-melting compounds

Translated from Poroshkovaya Metallurgiya, No. 11, pp. 79–83, November, 1990.