NO2 sensor and preparation method thereof

A technology of sensors and epitaxial thin films, which is applied in the field of NO2 sensors based on WO3 epitaxial thin films and its preparation, can solve the problems of reduced sensitivity, low barriers to mass production repeatability, long response time, etc., to achieve improved detection capabilities and stability, micro Compatibility with processing technology and the effect of improving detection efficiency

Active Publication Date: 2016-11-16
SUZHOU UNIV OF SCI & TECH
View PDF16 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

These nanomaterials are usually monoclinic phase WO which is stable at room temperature and has low surface energy. 3 , so the response time is generally longer (>120s)
Moreover, nanomaterials are prone to agglomeration during the production and use of sensors, resulting in unstable sensor performance, such as reduced sensitivity, baseline resistance drift, etc.
At the same time, WO 3 The complex preparation process and low repeatability of mass production hinder the promotion and popularization of nanomaterials

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
  • NO2 sensor and preparation method thereof
  • NO2 sensor and preparation method thereof
  • NO2 sensor and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] See attached figure 1 , which is the NO provided by this example 2 Schematic diagram of the sensor structure with SrTiO 3 (001) is a single crystal substrate, and the sensor adopts the laser molecular beam epitaxy (Laser-MBE) method to grow WO on the oxide single crystal substrate 1 3 Epitaxial film 2, and then prepare test electrode 3, and in WO 3 Precious metal catalyst particles 4 are deposited on the surface of the epitaxial film to produce NO 2 sensor. The specific production process is as follows:

[0028] (1) Cleaning SrTiO 3 (001) single crystal substrate. SrTiO 3 (001) The single crystal substrate was ultrasonically cleaned in acetone solution for 5 minutes, rinsed with deionized water and corroded in HF solution for 5 minutes, then rinsed with deionized water and dried to obtain a clean single crystal substrate.

[0029] (2) Growing WO 3 epitaxial film. SrTiO 3 The (001) single crystal substrate is placed in a laser molecular beam epitaxy device an...

Embodiment 2

[0036] The materials and process steps used in this example are basically the same as in Example 1, only the WO in step (2) 3 The growth rate of the epitaxial film was adjusted to 10 nm / s.

[0037] XRD and RHEED test results show that the deposited WO 3 The film is an epitaxial film with good crystalline quality, and its effect on NO 2 The test result is comparable with embodiment 1.

Embodiment 3

[0039] NO provided by this example 2 Sensor, the preparation steps are as follows:

[0040] (1) Cleaning SrTiO 3 (001) single crystal substrate. SrTiO 3 (001) The single crystal substrate was ultrasonically cleaned in acetone solution for 5 minutes, rinsed with deionized water and corroded in HF solution for 5 minutes, then rinsed with deionized water and dried to obtain a clean single crystal substrate.

[0041] (2) Growing WO 3 epitaxial film. SrTiO 3 The (001) single crystal substrate is placed in a laser molecular beam epitaxy device and heated to 600°C. Bombardment of WO with 1Hz, 350mW pulsed KrF laser 3 solid target surface, enabling WO 3 Material evaporates instantly and deposits onto SrTiO 3 (001) single crystal substrate surface to obtain WO 3 For epitaxial thin films, the growth rate is about 0.01nm / s.

[0042] (3) Sputtering deposition method in WO 3 Fabrication of Pt particles on the surface of epitaxial thin film as NO 2 detected catalyst.

[0043]...

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 an NO2 sensor and a preparation method thereof. The sensor comprises an oxide single crystal substrate, a WO3 epitaxial thin film, test electrodes and noble metal catalysts. The concentration of the NO2 gas in the environment is calibrated by measuring change of the resistance value of the WO3 epitaxial thin film between the test electrodes. Distortion and tilting of a structural motif WO6 octahedron of the WO3 epitaxial thin film are achieved by regulating the stress on the interface of the oxide single crystal substrate and the WO3 epitaxial thin film to obtain the WO3 epitaxial thin film with specific crystalline phase and exposed crystal plane, higher surface activity and reaction site concentrations and stable properties, thereby improving the detectivity and stability of the NO2 sensor. The sensor provided by the invention can be used for detecting NO2 with concentration of 40mu g/m<3>-20mg/m<3>, has short response time and stable properties, can be used for monitoring the concentration of NO2 in the atmospheric environment in real time and has a broad application prospect.

Description

technical field [0001] The invention belongs to the technical field of metal oxide-based resistance type gas sensing, and specifically relates to a WO-based 3 NO of epitaxial film 2 Sensors and methods of making them. Background technique [0002] With the rapid economic development, nitrogen dioxide (NO2) emitted from automobiles and factories 2 ) has become one of the main air pollutants, seriously threatening human health. World Health Organization research shows that people with lower immunity 2 The concentration is 20~200μg / m 3 If you live in the environment for 1 to 8 hours, symptoms such as decreased lung function and airway inflammation will appear. when NO 2 The concentration is 41.7mg / m 3 , even short-term exposure can be life-threatening. Therefore, both China and WHO will NO 2 The 1-hour concentration limit and the annual average concentration limit are set at 200 μg / m 3 and 40μg / m 3 . [0003] Currently widely used NO 2 Detection techniques include ...

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): G01N27/12
CPCG01N27/12G01N27/127
Inventor 赵蒙高炬刘国珍
Owner SUZHOU UNIV OF SCI & 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