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CN-121990609-A - Bi2WO6/ZnIn2S4Ag ternary grading heterojunction, and preparation method and application thereof

CN121990609ACN 121990609 ACN121990609 ACN 121990609ACN-121990609-A

Abstract

The application belongs to the technical field of new materials and electronic information, and particularly relates to a Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction, a preparation method and application thereof. The Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction comprises a substrate Bi 2 WO 6 nano-plate, znIn 2 S 4 nano-sheets densely inlaid on the surface of the Bi 2 WO 6 nano-plate and Ag nano-particles uniformly dispersed on the ZnIn 2 S 4 nano-sheets, wherein the Bi 2 WO 6 nano-plate and the ZnIn 2 S 4 nano-sheets form a semiconductor hetero-interface, and the Ag nano-particles form a semiconductor-metal hetero-interface on the surface of the ZnIn 2 S 4 nano-sheets. The preparation process is simple, the cost is low, and the prepared ternary graded heterojunction can be applied to a gas sensor, and particularly can be used for detecting the triethylamine in a high selectivity way at a relatively low working temperature of 275 ℃.

Inventors

  • SUN HAI
  • YANG YONG
  • LIANG YAN
  • DUAN QIXI
  • ZHU ZHENYU
  • Fang Zhaolong

Assignees

  • 江西师范大学

Dates

Publication Date
20260508
Application Date
20251222

Claims (10)

  1. 1. A Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction is characterized in that, The Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction comprises a substrate Bi 2 WO 6 nano-plate, znIn 2 S 4 nano-sheets densely inlaid on the surface of the Bi 2 WO 6 nano-plate and Ag nano-particles uniformly dispersed on the ZnIn 2 S 4 nano-sheets; The Bi 2 WO 6 nano-plate and the ZnIn 2 S 4 nano-plate form a semiconductor hetero-interface, and the Ag nano-particles form a semiconductor-metal hetero-interface on the surface of the ZnIn 2 S 4 nano-plate.
  2. 2. The Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction according to claim 1, wherein, The longitudinal dimension of the Bi 2 WO 6 nano-plate is 2-10 mu m, the thickness of the ZnIn 2 S 4 nano-plate package is 10-50 nm, and the dimension of the Ag nano-particles is 1-20 nm.
  3. 3. The Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction according to claim 1, wherein, The load capacity of the Ag nano particles is 1 wt% -3 wt%; the specific surface area of Bi 2 WO 6 /ZnIn 2 S 4 /Ag is 20m 2 /g~40 m 2 /g.
  4. 4. A method for preparing a Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction as claimed in any one of claims 1 to 3, comprising the steps of: Dissolving zinc chloride, indium chloride and thioacetamide in water, adjusting the pH value to 1-3, adding a Bi 2 WO 6 nano plate for water bath reaction, washing and drying after the reaction is finished to obtain a Bi 2 WO 6 /ZnIn 2 S 4 heterojunction; And (3) dissolving the silver nitrate solution and the Bi 2 WO 6 /ZnIn 2 S 4 heterojunction in water, uniformly mixing, then carrying out a photo-deposition reaction, washing and drying after the reaction is finished, and obtaining the Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction.
  5. 5. The method of claim 4, wherein the Bi 2 WO 6 nano-plate is prepared by: mixing bismuth oxide, tungsten oxide and sodium chloride, adding ethanol for grinding, drying and annealing after grinding, washing and drying after annealing, and obtaining the Bi 2 WO 6 nano-plate.
  6. 6. The method according to claim 5, wherein the molar ratio of bismuth oxide, tungsten oxide and sodium chloride is 1:1 to 3:5; The temperature of the annealing treatment is 600-700 ℃, and the time of the annealing treatment is 3-5 hours.
  7. 7. The preparation method according to claim 4, wherein the molar ratio of zinc chloride, indium chloride and thioacetamide is 1:1-3:1-4; The temperature of the water bath reaction is 60-100 ℃, and the time of the water bath reaction is 1-3 h.
  8. 8. The method according to claim 4, wherein, The concentration of the silver nitrate is 0.01 g/mol-0.04 g/mol; The dosage ratio of the Bi 2 WO 6/ ZnIn 2 S 4 heterojunction to the silver nitrate is 50 mg~200 mg:0.1 mL~0.5 mL; the power of the mercury lamp is 600-1200W during the photo-deposition reaction, and the irradiation time is 0.3-1.0 h.
  9. 9. A gas sensor comprising a Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction as defined in any one of claims 1 to 3.
  10. 10. Use of a Bi 2 WO 6 /ZnIn 2 S 4 /Ag ternary graded heterojunction as defined in any one of claims 1 to 3 or a gas sensor as defined in claim 9 for detecting triethylamine gas.

Description

Bi 2WO6/ZnIn2S4/Ag ternary graded heterojunction as well as preparation method and application thereof Technical Field The application belongs to the technical field of new materials and electronic information, and particularly relates to a Bi 2WO6/ZnIn2S4/Ag ternary graded heterojunction, a preparation method and application thereof. Background The resistance type gas sensor based on the semiconductor gas-sensitive material is one of the most common and widely applied gas sensors, and has wide application prospect in the detection of Volatile Organic Compounds (VOCs) gas. However, its gas-sensitive properties still fall far behind the theoretical and practical requirements. The development of highly effective VOCs gas sensing materials has become a research hotspot in recent years. The gas sensor is widely applied to various fields of industry and life such as chemical industry, metallurgy, environmental protection, medical treatment, food and the like. Development of new and efficient sensitive materials is a current research focus in the field of gas sensors. Metal Oxide Semiconductor (MOS) sensors show great promise in identifying various gases due to their low cost, ease of operation and mobility. Many MOS sensors include ZnO, in 2O3、SnO2、Co3O4, cuO, and TiO 2 for monitoring VOCs. Currently, bi 2WO6 is successfully used as a sensor material due to its excellent electron transport efficiency, crystal structure stability, and compatibility with the environment. Despite the extensive literature on Bi 2WO6 sensing materials, pure Bi 2WO6 materials still have higher operating temperatures and poorer VOCs selectivity, meaning that the gas detection performance of pure Bi 2WO6 needs to be further enhanced and optimized. Constructing heterostructures (including semiconductor heterostructures, semiconductor/metal heterostructures, etc.) is an important strategy to improve the gas-sensitive performance of semiconductor gas-sensitive materials. In practice, due to lattice structure or band structure mismatch, it is difficult in many cases to form a strong and tight heterostructure interface between semiconductor elements or between semiconductor and metal. This makes it difficult to achieve efficient charge transfer between the components, resulting in an inability to efficiently convert the charge signal of the gas-solid reaction into a resistance signal, which greatly hinders further improvement of the gas-sensitive performance. In particular, designing a multi-interface ternary heterostructure with close robustness remains a significant challenge compared to common binary semiconductor heterostructures or semiconductor/metal heterostructures. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a Bi 2WO6/ZnIn2S4/Ag ternary graded heterojunction, a preparation method and application thereof, and the technical scheme is as follows: In a first aspect, the invention provides a ternary graded Bi 2WO6/ZnIn2S4/Ag heterojunction, The Bi 2WO6/ZnIn2S4/Ag ternary graded heterojunction comprises a substrate Bi 2WO6 nano-plate, znIn 2S4 nano-sheets densely inlaid on the surface of the Bi 2WO6 nano-plate and Ag nano-particles uniformly dispersed on the ZnIn 2S4 nano-sheets; The Bi 2WO6 nano-plate and the ZnIn 2S4 nano-plate form a semiconductor hetero-interface, and the Ag nano-particles form a semiconductor-metal hetero-interface on the surface of the ZnIn 2S4 nano-plate. The invention provides a Bi 2WO6/ZnIn2S4/Ag ternary grading heterojunction gas sensor which is composed of a Bi 2WO6 nano plate serving as a substrate, a ZnIn 2S4 nano plate inlaid on the surface of the Bi 2WO6 nano plate and Ag nano particles with the outermost layer being highly dispersed. It is capable of providing excellent sensing performance for the detection of the volatile organic compound triethylamine, exhibiting a significant response to 100 ppm triethylamine of about 128.94 (R a/Rg) at a relatively low operating temperature of 275 ℃, while having excellent response/recovery rate and selectivity, and long lasting stability (over 60 days). Most importantly, a robust semiconductor hetero-interface (Bi 2WO6/ZnIn2S4) and a semiconductor-metal hetero-interface (ZnIn 2S4/Ag) are formed in the ternary heterostructure, achieving efficient multi-interface charge transfer characteristics. In addition, due to the design of the 2D/2D/0D structure, the Bi 2WO6/ZnIn2S4/Ag ternary graded heterojunction not only has larger gas adsorption and reaction specific surface area, but also improves the stability of Bi 2WO6. The invention provides a new visual angle for improving the gas-sensitive performance of the semiconductor material by comprehensively designing the ternary heterostructure with multiple interfaces. As a further preferable implementation mode, the longitudinal dimension of the Bi 2WO6 nano-plate is 2-10 mu m, the thickness of the ZnIn 2S4 nano-plate package is 10-50 nm, and the dimension of the Ag nano-part