Gas sensitive element taking houghite as precursor and preparation method thereof

A technology of gas sensor and hydrotalcite, which is applied in the field of gas sensor to achieve the effect of simple preparation steps, diversified element composition and good stability

Inactive Publication Date: 2012-08-08
BEIJING UNIV OF CHEM TECH
View PDF6 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

According to the uniform nature of the elements contained in hydrotalcite, it is roasted to form a composite oxide to make a gas sensor. There are few reports on the gas sensor properties of this type of gas sensor.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Gas sensitive element taking houghite as precursor and preparation method thereof
  • Gas sensitive element taking houghite as precursor and preparation method thereof
  • Gas sensitive element taking houghite as precursor and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] 1. Preparation of hydrotalcite with nitrate between layers by double drop method:

[0023] 0.02mol of solid Zn(NO 3 ) 2 ·6H 2 O and 0.01mol of solid Al(NO 3 ) 3 9H 2 O dissolved in 100ml of deCO 2 Make a mixed salt solution in water, dissolve 0.08mol NaOH in 100ml deCO 2 Make an alkaline solution in deionized water, and then under the protection of nitrogen, drop the two solutions into a four-necked flask at the same time while stirring, control the dropping speed of the alkaline solution, keep the pH of the solution in the flask in the range of 6.5-7, and titrate After completion, continue to stir for 30 minutes, hydrothermal crystallization at 100°C for 12 hours, and use CO removal 2 Centrifuge and wash with water until neutral, and dry at 60°C for 24 hours to obtain nitrate intercalated hydrotalcite. The obtained hydrotalcite is calcined at a temperature of 600° C. at a heating rate of 10° C. / min, and kept for 5 hours to form a composite oxide, that is, a sem...

Embodiment 2

[0035] 1. Preparation of hydrotalcite with nitrate between layers by single drop method:

[0036] a, 0.02mol of solid Zn(NO 3 ) 2 ·6H 2 O, 0.01mol of solid Al(NO 3 ) 3 9H 2 O and 0.001 mol of solid La(NO 3 ) 3 · 4H2O dissolved in 100ml of deCO 2 Make a mixed salt solution in water, dissolve it evenly and transfer it to a four-neck flask, dissolve 0.08mol of NaOH in 100ml of CO 2 The solution prepared in ionized water was transferred to the constant pressure dripping funnel, and then under the protection of nitrogen, the lye was slowly dropped into the flask while stirring, and the pH of the solution was controlled within the range of 5.5-6.5. After the titration was completed, continue to stir for 30 Minutes, hydrothermal crystallization at 100°C for 24 hours, using CO removal 2 Centrifugal washing with ion water until neutral, drying at 60°C for 24 hours to obtain nitrate intercalated hydrotalcite.

[0037] b. Set the obtained hydrotalcite at 1000°C to roast at a he...

Embodiment 3

[0041] 1. Preparation of hydrotalcite with nitrate between layers by double drop method:

[0042] a, 0.02mol of solid Zn(NO 3 ) 2 ·6H 2 O, 0.01mol of solid Al(NO 3 ) 3 9H 2 O and 0.001mol of solid In(NO 3 ) 3 4H 2 O dissolved in 100ml of deCO 2 Make a mixed salt solution in water, dissolve it evenly and transfer it to a four-neck flask, dissolve 0.08mol of NaOH in 100ml of CO 2 The solution prepared in ionized water was transferred to the constant pressure dripping funnel, and then under the protection of nitrogen, the lye was slowly dropped into the flask while stirring, and the pH of the solution was controlled within the range of 5.5-6.5. After the titration was completed, continue to stir for 30 Minutes, hydrothermal crystallization at 100°C for 24 hours, using CO removal 2 Centrifuge and wash with water until neutral, and dry at 60°C for 24 hours to obtain nitrate intercalated hydrotalcite.

[0043] b. Set the obtained hydrotalcite at 800°C to roast at a heatin...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for preparing a gas sensitive element by taking houghite as a precursor, which belongs to the technical field of gas sensitive sensors. The method comprises the following steps of: preparing houghite by using a co-precipitation method; roasting the houghite at different temperatures to form a compound semiconductor metal oxide material; and preparing into a gas sensitive element, wherein the gas sensitive element can be used for detecting various gases by measuring the resistance values of the element in different gases. The gas sensitive element has the major advantages of simple preparation steps, low cost, diversified element compositions, and uniform distribution of elements of a compound oxide formed by roasting. The gas sensitive element prepared from the method has the advantages of high sensitivity, quick response and recovery, high stability, great developing potential and contribution to popularization.

Description

technical field [0001] The invention belongs to the technical field of gas sensing, and in particular relates to the preparation of a class of Zn-containing hydrotalcite, which is roasted to obtain a ZnO-containing composite metal oxide material, which is fabricated into a gas-sensing element, and its gas-sensing properties are explored. Background technique [0002] ZnO is the earliest discovered semiconductor gas-sensing material, which is characterized by wide bandgap (band gap of 3.2eV), excellent photoelectric, piezoelectric and other properties, and stable physical and chemical properties. It sublimes only at 1800°C, can work at higher temperatures, and is cheap and easy to prepare, so it has attracted more and more attention. The performance of pure ZnO gas sensor is not stable enough, the sensitivity is low, the working temperature is high, the selectivity is relatively poor, and the resistance in the air is too high. In order to improve its gas-sensing performance,...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N27/04C01G9/02
Inventor 郭影关美玉徐冬梅宋宇飞徐庆红
Owner BEIJING UNIV OF CHEM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap