Prepn of oxygen-sensing sensor

Abstract

The preparation of oxygen-sensing sensor includes the steps of: preparation of titanium trichloride doped with certain amount of niobium or tantalum pentachloride as source matter; addition of hydrogen peroxide as strong oxidant and DBS surface cladding agent and stirring at 50-70 deg.c water bath for 3-5 hr to form gel; mixing obtained powder with terpineol and painting the mixture to ceramic tube with brush-type electrodes; sintering in a muffle furnace at 380-450 deg.c for 1 hr to prepare niobium or tantalum pentachloride doped TiO2 nanometer powder, addition of heating filament to preparethe thick-film oxygen-sensing element; and aging through electrical heating for 10 dyas. The present invention has low working temperature, high sensitivity, fast response and high stability.

Description

Technical field: [0001] The invention relates to a preparation method of an oxygen sensitive sensor, to be precise, it belongs to a preparation method of a nanometer functional material. Background technique: [0002] Oxygen is one of the most abundant elements on the earth and is closely related to human activities. Many fields involve oxygen measurement. For example, in the automobile exhaust purifier, by measuring the oxygen content in the exhaust gas, the pollution of harmful gases in the exhaust gas can be controlled and reduced, and the efficiency can be improved; in order to monitor the combustion conditions of the coal (oil) boiler, the air ( Oil) ratio, to achieve the purpose of energy saving and environmental protection; hypoxia detection (hypoxia instrument) in the working environment; clinical aerobic treatment in medical treatment, as well as atmospheric environmental protection monitoring, bioengineering, aerospace, petrochemical and other aspects need Equippe...

AI Technical Summary

Problems solved by technology

[0003] However, at present, only ZrO is relatively mature and practical. 2 Electrolyte oxygen sensor and bulk TiO for monitoring automobile exhaust 2 Oxygen sensor, the former has a high working temperature (≥600°C), is expensive, and the better quality is imported. Because it needs to be doped with precious metals, it is easy to cause poisoning failure, and it needs reference, complex structure, and regular replacement. ; while the latter has a narrow range of oxygen sensitivity and can only be used at high temperatures (≥700°C), which limits its application in other areas

in TiO 2 In terms of research on oxygen-based oxygen sensors, several research institutions at home and abroad are also pursuing low-working temperature semiconductor oxygen sensors, but they all use tetravalent titanium salt as the source material, and cannot obtain oxygen-sensitive phase-rutile phase at low sintering temperature. , and high-temperature sintering will cause defects such as large grains, easy agglomeration, and reduced surface activity, and it needs to work at high temperatures. The lowest working temperature currently obtained is 250 ° C (Australian scholars), which still cannot meet the practical needs.

[0004] It can be seen from the search literature that the application number is 94102375, and the application date is March 09, 1994. The name is the method for preparing titanium oxide-niobium oxide composite oxide oxygen-sensitive materials. The method of solid-phase synthesis adopted by the inventor Peng Jun, although Its material belongs to the same semiconductor type as the present invention, and both are titanium dioxide doped with niobium oxide, but the preparation method is different from that of the present invention, and its working temperature is as high as 720°C

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