Abstract: Nanostructured γ-Fe2O3/SiO2 complex oxide was prepared by sol-gel method with
tetraethoxysilane and iron nitrate as precursors. The particle size distribution, thermal
and phase stabilities and gas sensing properties were systematically characterized by TEM,
granularity distribution, TG-DTA, XRD and gas sensitivity measurements. The particle size
is about 10 nm and size distribution is very narrow. The sensitivity of the sensing element
to CO, H2, C2H4, C6H6 and the effects of calcination temperature on the sensitivity and
conductance of gases were examined. The combination of excellent thermal stability and
tunable gas sensing properties through careful control of the preparation and judicious
selection of material compositions gives rise to novel nanocomposites, which is attractive
for the sensitive and selective detection of reducing gases and some hydrocarbon gases.

Key words: nanostructural composites, Fe₂O₃, SiO₂, gas-sensing properties

摘要： Nanostructured γ-Fe2O3/SiO2 complex oxide was prepared by sol-gel method with
tetraethoxysilane and iron nitrate as precursors. The particle size distribution, thermal
and phase stabilities and gas sensing properties were systematically characterized by TEM,
granularity distribution, TG-DTA, XRD and gas sensitivity measurements. The particle size
is about 10 nm and size distribution is very narrow. The sensitivity of the sensing element
to CO, H2, C2H4, C6H6 and the effects of calcination temperature on the sensitivity and
conductance of gases were examined. The combination of excellent thermal stability and
tunable gas sensing properties through careful control of the preparation and judicious
selection of material compositions gives rise to novel nanocomposites, which is attractive
for the sensitive and selective detection of reducing gases and some hydrocarbon gases.

关键词: 气敏性质;γ-Fe₂O₃;SiO₂;化合物;氧化物;硝酸钾;接触反应;氧化反应