Preparation method for gas-sensitive material with composite structure

A gas-sensitive material and composite structure technology, which is applied in the field of preparation of porous silicon-based tungsten oxide composite structure gas-sensitive materials, and achieves the effects of easy control of process parameters, convenient operation and low cost

Inactive Publication Date: 2013-04-24
TIANJIN UNIV
View PDF1 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to overcome the shortcomings of a single gas-sensing material, and to provide a method for preparing a porous silicon-based tungsten oxide nano-film containing a large amount of oxygen vacancies, which can significantly increase the specific surface area of ​​the sensitive material, and utilize The heterojunction formed by charge transfer between two semiconductor materials changes the redox potential of the surface of the tungsten oxide film, thereby further improving the response to the detection gas

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
  • Preparation method for gas-sensitive material with composite structure
  • Preparation method for gas-sensitive material with composite structure
  • Preparation method for gas-sensitive material with composite structure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] (1) Clean the silicon substrate

[0033] Cut a 2-inch n-type single-sided polished single-crystal silicon wafer with a resistivity of 0.01Ω·cm, a thickness of 400μm, and (100) crystal orientation into rectangular silicon substrates with a size of 2.4cm×0.9cm, and put them in acetone in turn Solvent, absolute ethanol and deionized water were ultrasonically cleaned for 20 minutes, and then soaked in 5% hydrofluoric acid aqueous solution for 15 minutes, and then washed with deionized water for later use;

[0034] (2) Preparation of porous silicon

[0035] A porous silicon layer was prepared on the polished surface of a silicon wafer by a double-tank electrochemical method. The corrosion electrolyte used is composed of hydrofluoric acid and deionized water with a mass fraction of 40%, the volume ratio is 1:5, no surfactant and additional light are added, and the applied corrosion current density is 125mA / cm 2 , the etching time is 20min; wherein the porous silicon formati...

Embodiment 2

[0040] The difference between this example and Example 1 is that the sputtering time of the tungsten oxide nano-film in step (3) is 5 minutes, and the porous silicon-based tungsten oxide composite structure gas-sensing material is prepared. Scanning electron microscopy analysis of the surface morphology showed that figure 2 As shown, the tungsten oxide film has not been uniformly covered on the surface, and there are a lot of holes.

Embodiment 3

[0042] The difference between this example and Example 1 is that the sputtering time of the tungsten oxide nano-film in step (3) is 8 minutes, and the porous silicon-based tungsten oxide composite structure gas-sensing material is prepared. Scanning electron microscopy analysis of the surface morphology showed that image 3 As shown, the surface structure of the film is extremely loose, and there are a large number of deep holes.

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

PropertyMeasurementUnit
electrical resistivityaaaaaaaaaa
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method for a gas-sensitive material with a composite structure. The preparation method comprises the following steps: (1) successively placing an n-type single-side polished monocrystalline silicon chip into an acetone solvent, absolute ethyl alcohol and deionized water for ultrasonic cleaning, then soaking the monocrystalline silicon chip in 5% of an aqueous hydrofluoric acid solution, flushing the monocrystalline silicon chip with ionized water and standing the monocrystalline silicon chip for subsequent usage; (2) preparing a porous silicon layer on the polished surface of the cleaned silicon chip by using a double-tank electrochemical corrosion process, wherein corrosion current density is 115 to 135 mA/cm<2> and corrosion time is 20 to 25 min; and (3) with metal tungsten as a target material, sputtering and depositing a nanometer tungsten oxide film on the surface of silicon-based porous silicon and carrying out heat treatment at a temperature of 450 to 500 DEG C for 3 to 4 h so as to prepare the gas-sensitive material with the composite structure. The invention provides a method for preparing the nanometer tungsten oxide film with a loose porous surface and containing considerable oxygen vacancies, the method has the advantages of simple equipment, convenient operation, easily controllable technological parameters and low cost, and the nanometer tungsten oxide film is fairly applicable to the gas-sensitive material.

Description

technical field [0001] The invention relates to a gas-sensing material with a composite structure, in particular to a preparation method for a gas-sensing material with a porous silicon-based tungsten oxide composite structure. Background technique [0002] The rapid development of modern industrial technology has had a huge impact on the progress of human civilization and the ecological environment. A large number of toxic and harmful gases and flammable gases (such as NO 2 , NH 3 , CO and H 2 etc.) While polluting the environment, it also seriously threatens human health and safety. With the improvement of people's living standards and the enhancement of environmental awareness, the requirements for the ecological environment are also getting higher and higher. The detection technology of toxic and harmful gases has attracted more and more attention and attention from all over the world. Countries have formulated relevant policies and detection standards, which provides...

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): G01N27/02G01N27/60B82Y15/00
Inventor 胡明李明达贾丁立马双云曾鹏
Owner TIANJIN UNIV
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