阅读说明：本技术 一种感知/换能耦合自驱动气体传感器及其制备方法 (Sensing/transduction coupling self-driven gas sensor and preparation method thereof ) 是由 苏元捷 姚明亮 谢光忠 龚祺琛 陈春旭 衣锦扬 贾砾 黎威志 蒋亚东 于 2020-05-11 设计创作，主要内容包括：本发明涉及一种感知/换能耦合自驱动气体传感器及其制备方法,传感器结构从下到上包括柔性基底,柔性叉指电极,介电聚合物基气敏材料与压电陶瓷颗粒组成的气敏复合薄膜。本发明将气敏材料和压电换能材料集成在一起,充分融合了介电气敏聚合物室温气体探测、柔性,以及压电陶瓷高压电响应的特点,利用外力激励促使气敏与换能交叉耦合并“无源”地转化为探测电信号,实现气敏/换能耦合自驱动气体检测,解决了当今绝大多数气体传感器的“气敏”与“换能”过程都是独立、割裂的问题。本发明提出气敏与换能同时同地地交叉耦合,并实现协同增效,具有零功耗、高灵敏、柔性化、便于集成等特点,可用于自驱动环境监控和人体生理监测,无需配备电源。(The invention relates to a sensing/transduction coupling self-driven gas sensor and a preparation method thereof. The invention integrates the gas sensitive material and the piezoelectric transduction material together, fully integrates the characteristics of room temperature gas detection, flexibility and piezoelectric ceramic high-voltage electricity response of the dielectric gas sensitive polymer, utilizes external force excitation to promote gas sensitivity and transduction cross coupling and 'passive' conversion into detection electric signals, realizes gas sensitivity/transduction coupling self-driven gas detection, and solves the problem that the 'gas sensitivity' and 'transduction' processes of most of the current gas sensors are independent and split. The invention provides the gas-sensitive and energy-converting simultaneous same-ground cross coupling, realizes the synergy, has the characteristics of zero power consumption, high sensitivity, flexibility, convenience for integration and the like, can be used for self-driven environment monitoring and human body physiological monitoring, and does not need to be provided with a power supply.)

1. A perception/transduction coupling self-driven gas sensor is characterized in that the self-powered gas sensor structurally comprises a flexible substrate, flexible interdigital electrodes and a piezoelectric ceramic-gas-sensitive polymer composite film, wherein the flexible interdigital electrodes are arranged on the flexible substrate, and piezoelectric ceramic particles are compounded with a dielectric polymer gas-sensitive material and deposited on the flexible interdigital electrodes; a gas sensitive interface is arranged above the composite film, and a transduction interface is arranged below the composite film and the interface of the flexible interdigital electrode; the flexible interdigital electrode is led out through a lead for detecting an electric signal output by the sensor.

2. The sensor of claim 1, wherein the gas sensitive material and the piezoelectric transducer material are integrated, and external force is used to excite the cross coupling between gas sensing and transducer and transform the cross coupling into detection electrical signal, so as to realize gas sensing/transducer coupling self-driven gas detection.

3. The sensor of claim 2, wherein the stress applied to the composite membrane is compressive, tensile or bending.

4. The sensor/transducer coupled self-driven gas sensor as claimed in claim 1, wherein the volume fraction of the doping amount of the piezoelectric ceramic particles and the piezoelectric ceramic in the dielectric polymer gas-sensitive material composite material is 10-60%, and the thickness of the composite material film is 10-500 nm.

5. The sensor/transducer coupled self-driven gas sensor according to claim 1, wherein the dielectric polymer gas-sensitive material is a composite film made of one or more different materials selected from polyaniline, polyethylene oxide, polyethylene imine, sodium polystyrene sulfonate, polyaniline, polyimide, chitosan and graphene oxide.

6. The sensor/transducer coupled self-driven gas sensor according to claim 1, wherein the piezoelectric ceramic particles are made of any one of barium titanate piezoelectric ceramic, lead zirconate titanate piezoelectric ceramic, niobate piezoelectric ceramic, potassium sodium niobate, and lead magnesium niobate piezoelectric ceramic.

7. The sensor of claim 1, wherein the flexible substrate comprises polyimide, polytetrafluoroethylene, polyvinyl fluoride, polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyethylene naphthalate.

8. The sensor/transduction coupling self-driven gas sensor according to claim 1, wherein the interdigital electrodes are deposited on the flexible substrate by evaporation or sputtering, and the thickness of the interdigital electrodes is about 10-50 μm; the gas-sensitive material is deposited on the interdigital electrode by adopting any one of electrostatic spinning, tape casting, spin coating, spraying, drop coating, sol-gel, self-assembly and chemical vapor deposition and combining a stripping process to form a gas-sensitive structure.

9. A method for preparing a sensing/transducing coupled self-driven gas sensor according to any one of claims 1 to 9, comprising the following steps:

(1) cleaning and drying the flexible substrate by using a chemical reagent;

(2) depositing an interdigital electrode on a flexible substrate by adopting a sputtering or evaporation process;

(3) mixing a piezoceramic material and a gas-sensitive material for standby;

(4) depositing the piezoelectric ceramic-gas-sensitive mixed material on the interdigital electrodes by adopting any one of electrostatic spinning, tape casting, spin coating, spraying, drop coating, sol-gel, self-assembly and chemical vapor deposition and combining a stripping process to form a gas-sensitive structure;

(5) and (5) polarizing the gas-sensitive composite material.

10. The method for preparing a sensor/transducer coupled self-driven gas sensor as claimed in claim 9, wherein a polarization process is performed on the interdigital electrode, and the gas-sensitive composite material has polarization process parameters of a polarization electric field strength of 0.1kv/mm to 100kv/mm, a polarization temperature of 20 ℃ to 200 ℃ and a polarization time of 60min to 600 min.

Technical Field

The invention relates to the technical field of energy collection, micro-electro-mechanical systems (MEMS) and electronic polymer sensitive materials, in particular to a sensing/transduction coupling self-driven gas sensor and a preparation method thereof.

Background

With the development of modern industry, people enjoy more and more convenience and suffer more and more serious environmental pollution hazards. According to the release of World Health Organization (WHO) surveys, nearly ten million people die each year due to environmental pollution or premature death. The source of harmful gas in the air is wide, and the harmful gas is generated in the combustion of coal, petroleum, natural gas and the like, industrial production processes, tail gas discharged by vehicles in transportation processes, underground mining and tunneling construction processes and the like. Volatile organic pollutant gases (formaldehyde, benzene and benzene compounds, methanol, acetone and the like) can be encountered everywhere in life, and are harmful to human health all the time, and once diseases are caused, the situation that the pollutants cannot be reversed and cannot be recovered is achieved.

Secondly, along with the rapid development of world economy, the demand of human society for energy supply is getting larger and larger, and the nonrenewable traditional energy supply modes such as coal, petroleum, natural gas, nuclear energy and the like cannot meet the development demand of the times due to the serious pollution to the environment, so that the research of clean and renewable new energy is a problem which needs to be solved urgently at present. New energy resources, such as mechanical energy, heat energy, solar energy and the like, which are recycled and regenerated are gradually recognized, developed and utilized by people in the past decades, and the new energy technology is utilized to provide effective measures for environmental management and ecological protection, so that the new energy resource technology is an important solution for overcoming global energy shortage and meeting sustainable development of human society.

The mechanical energy in the environment is one of the most ideal alternative energy sources due to the advantages of wide distribution, various expression forms, easy conversion and the like. If the mechanical energy in the environment can be collected and stored by using an effective means and converted into electric energy, the electric energy can be used for supplying power and continuing the journey for the operation of microelectronic devices such as implantable medical equipment, a sensing system, a wearable electronic device, portable equipment and the like, so that the limitation of the problems of large size, short service life, poor safety and the like caused by the conventional battery power supply is broken through.

Disclosure of Invention

The invention aims to: the device embeds piezoelectric transduction materials into polymer gas-sensitive materials, excites cross coupling of gas sensitivity and transduction through external force and converts the cross coupling into detection electric signals passively so as to realize real-time spontaneous active detection on gas types and concentrations.

The technical scheme adopted by the invention is as follows:

a perception/transduction coupling self-driven gas sensor structurally comprises a flexible substrate, flexible interdigital electrodes and a piezoelectric ceramic-gas-sensitive polymer composite film, wherein the flexible interdigital electrodes are arranged on the flexible substrate, piezoelectric ceramic particles are compounded with a dielectric polymer gas-sensitive material and are deposited on the flexible interdigital electrodes; a gas sensitive interface is arranged above the composite film, and a transduction interface is arranged below the composite film and the interface of the flexible interdigital electrode; the flexible interdigital electrode is led out through a lead for detecting an electric signal output by the sensor. The gas sensitive material and the piezoelectric transduction material are integrated together, and external force excitation is utilized to promote gas sensitivity and transduction cross coupling and passive conversion into detection electric signals, so that gas sensitivity/transduction coupling self-driven gas detection is realized.

The working principle of the device is that the gas reaction is utilized to change the dielectric constant of the gas-sensitive polymer, so that the electric field intensity distributed by two phases of the composite material is changed, the electric field intensity distributed on the piezoelectric ceramic is changed, and the external specific gas reaction is modulated to a piezoelectric output signal, so that the concentration of the external atmosphere can be reversely deduced through the size of the piezoelectric output, and the self-powered gas detection is realized.

Further, the stress applied on the composite film is extrusion, stretching or bending.

Furthermore, the volume fraction of the doping amount of the piezoelectric ceramic particles and the piezoelectric ceramic in the dielectric polymer gas-sensitive material composite material is 10-60%, and the thickness of the composite material film is 10-500 nm.

Further, the dielectric polymer gas-sensitive material is a composite film composed of any one or more of polyaniline, polyethylene oxide, polyethylene imine, sodium polystyrene sulfonate, polyaniline, polyimide, chitosan and graphene oxide.

Further, the piezoelectric ceramic particles are made of any one of barium titanate piezoelectric ceramics, lead zirconate titanate piezoelectric ceramics, niobate piezoelectric ceramics, potassium sodium niobate, and lead magnesium niobate piezoelectric ceramics.

Further, the flexible substrate includes polyimide, polytetrafluoroethylene, polyvinyl fluoride, and the like.

Further, depositing the interdigital electrode on the flexible substrate by adopting an evaporation or sputtering method, wherein the thickness of the interdigital electrode is about 10-50 μm; the gas-sensitive material is deposited on the interdigital electrode by adopting any one of electrostatic spinning, tape casting, spin coating, spraying, drop coating, sol-gel, self-assembly and chemical vapor deposition and combining a stripping process to form a gas-sensitive structure.

In order to achieve the above object, the present invention further provides a method for manufacturing a sensing/transduction coupling self-driven gas sensor, which specifically comprises the following steps:

(1) cleaning and drying the flexible substrate by using a chemical reagent;

(2) depositing an interdigital electrode on a flexible substrate by adopting a sputtering or evaporation process;

(3) mixing a piezoceramic material and a gas-sensitive material for standby;

(4) depositing the piezoelectric ceramic-gas-sensitive mixed material on the interdigital electrodes by adopting any one of electrostatic spinning, tape casting, spin coating, spraying, drop coating, sol-gel, self-assembly and chemical vapor deposition and combining a stripping process to form a gas-sensitive structure;

(5) and (5) polarizing the gas-sensitive composite material.

Furthermore, the polarization process acts on the interdigital electrode, and the polarization process parameters of the gas-sensitive composite material are that the field intensity of a polarization electric field is 0.1 kv/mm-100 kv/mm, the polarization temperature is 20 ℃ -200 ℃, and the polarization time is 60 min-600 min.

In summary, compared with the prior art, the invention has the following beneficial effects:

the traditional gas sensor is independent and split in gas sensitivity and energy conversion, so that the integration is inconvenient and the power consumption is reduced; the invention provides a perception/transduction coupling self-driven gas sensor and a preparation method thereof, the device embeds piezoelectric transduction material into polymer gas sensitive material, and excites the cross coupling of gas sensitivity and transduction through external force and converts the cross coupling into detection electric signal passively so as to realize the real-time spontaneous active detection of gas type and concentration; the invention provides a self-powered gas sensor sensitivity mechanism and a self-powered gas sensor sensitivity model based on a piezoelectric ceramic-dielectric gas-sensitive polymer, and provides a sensing/transduction coupling self-driven gas-sensitive structure which can independently work without external power supply; the advantages of piezoelectric ceramic high-voltage output response and room-temperature gas detection and flexibility of the gas-sensitive polymer material are fully combined, and flexible self-driven environmental atmosphere/human body exhaled gas monitoring can be realized.

Drawings

FIG. 1 is a schematic diagram of a self-driven gas sensor with sensing/transducing coupling according to the present invention;

fig. 2 is a diagram of a power generation mechanism of a sensing/transducing coupling self-driven gas sensor according to the present invention.

The reference signs are: 1-flexible substrate, 2-flexible interdigital electrode, 3-dielectric polymer gas sensitive material and 4-piezoelectric ceramic particles.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

The invention will be further described with reference to the accompanying figures 1-2 and examples.