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CN-122016975-A - Electric field enhanced self-powered humidity sensor and preparation method and application thereof

CN122016975ACN 122016975 ACN122016975 ACN 122016975ACN-122016975-A

Abstract

The invention relates to the technical field of humidity sensors, and particularly discloses an electric field enhanced self-powered humidity sensor, and a preparation method and application thereof. The sensor sequentially comprises an aluminum electrode layer, a filter paper middle layer and a copper electrode layer from top to bottom, wherein the copper electrode layer is completely overlapped with the lower surface of the filter paper middle layer, the aluminum electrode layer covers 60-80% of the upper surface area of the filter paper middle layer, 20-40% of the upper surface area of the filter paper middle layer is an exposed area, the aluminum electrode layer and the copper electrode layer form an asymmetric metal electrode, the filter paper middle layer is coated with a sensitive material, and the sensitive material is a potassium chloride modified h-C 3 N 4 /PVA composite material. According to the invention, the h-C 3 N 4 /PVA composite material modified by potassium chloride is adopted as a sensitive material, an asymmetric metal electrode is introduced into the sandwich structure, and an internal electric field consistent with the water diffusion direction is generated in the sensitive layer by utilizing the primary cell effect induced by humidity, so that the output voltage and response speed of the sensor are remarkably improved, and finally excellent response performance is presented.

Inventors

  • HU JINYONG
  • TANG JINGXIAN
  • QIN QIHENG
  • LIU BOHAO
  • ZHANG YONG

Assignees

  • 湘潭大学

Dates

Publication Date
20260512
Application Date
20260225

Claims (10)

  1. 1. The electric field enhanced self-powered humidity sensor is characterized by sequentially comprising an aluminum electrode layer, a filter paper middle layer and a copper electrode layer from top to bottom, wherein the copper electrode layer is completely overlapped with the lower surface of the filter paper middle layer, the aluminum electrode layer covers 60-80% of the upper surface area of the filter paper middle layer, 20-40% of the upper surface area of the filter paper middle layer is an exposed area, the aluminum electrode layer and the copper electrode layer form an asymmetric metal electrode, the filter paper middle layer is coated with a sensitive material, and the sensitive material is a potassium chloride modified h-C 3 N 4 /PVA composite material.
  2. 2. The electric field enhanced self-powered humidity sensor according to claim 1 wherein the filter paper is of a water-based porous type, pore diameter in the filter paper is 20-25 um, particle size of the potassium chloride modified h-C 3 N 4 particles is 200-300 nm, and thickness of the aluminum electrode layer and the copper electrode layer is 50-65 μm.
  3. 3. A method for manufacturing a self-powered humidity sensor with enhanced electric field as claimed in any one of claims 1 to 2, comprising the steps of: (1) Preparing a potassium chloride modified h-C 3 N 4 material; (2) Mixing the potassium chloride modified h-C 3 N 4 material with PVA to prepare a potassium chloride modified h-C 3 N 4 /PVA composite material; (3) Dipping the filter paper by adopting a potassium chloride modified h-C 3 N 4 /PVA composite material, and drying to obtain modified filter paper; (4) And respectively covering an aluminum electrode and a copper electrode on the upper surface and the lower surface of the modified filter paper to obtain the humidity sensor.
  4. 4. The method for preparing the electric field enhanced self-powered humidity sensor according to claim 3, wherein the step (1) comprises the steps of grinding and mixing NH 4 SCN and KCl uniformly, calcining at 500-600 ℃, dialyzing calcined powder in a dialysis bag, vacuum drying to obtain potassium chloride modified h-C 3 N 4 , and adding PVA particles into the potassium chloride modified h-C 3 N 4 to obtain the potassium chloride modified h-C 3 N 4 /PVA composite material.
  5. 5. The method for manufacturing a self-powered humidity sensor according to claim 4, wherein the weight ratio of NH 4 SCN to KCl is 8-12:1.
  6. 6. The method for preparing the electric field enhanced self-powered humidity sensor according to claim 3, wherein the step (2) specifically comprises the steps of adding a potassium chloride modified h-C 3 N 4 material and PVA into deionized water, and performing ultrasonic dispersion for 5-10 min to obtain the potassium chloride modified h-C 3 N 4 /PVA composite material.
  7. 7. The method for manufacturing an electric field enhanced self-powered humidity sensor according to claim 6, wherein the mass ratio of the potassium chloride modified h-C 3 N 4 material to PVA is 1-2:1-2.
  8. 8. The method for preparing the electric field enhanced self-powered humidity sensor according to claim 6, wherein the step (3) comprises immersing the filter paper in a potassium chloride modified h-C 3 N 4 /PVA composite material for 45-75 min, drying at 60-70 ℃, and repeating the immersing-drying for 3-4 times to obtain the modified filter paper.
  9. 9. The use of an electric field enhanced self-powered humidity sensor according to any one of claims 1-2 for real-time monitoring of moisture information.
  10. 10. Use of the electric field enhanced self-powered humidity sensor according to any one of claims 1-2 for the preparation of a non-contact switch, a non-contact keyboard, and/or a respiratory disease monitoring device.

Description

Electric field enhanced self-powered humidity sensor and preparation method and application thereof Technical Field The invention relates to the technical field of humidity sensors, in particular to an electric field enhanced self-powered humidity sensor, and a preparation method and application thereof. Background The sustainable development and low power consumption requirements of sensor nodes in the internet of things promote the development of low power consumption (even zero power consumption) electronic devices. Humidity is used as a key environmental parameter, and has important application value in various fields such as food preservation, agricultural monitoring, industrial production and the like. Therefore, an integrated sensor with the functions of power generation and humidity detection is developed, and a new technical path is provided for realizing self-powered humidity detection. In various self-powered technologies, the moisture generator (MEGs) is based on an asymmetric ion motion mechanism, stable electric energy output can be realized without depending on external mechanical energy, and the moisture generator has more continuous reliability compared with the friction nano generator (TENGs), so that the moisture generator is widely researched and focused. However, the conventional MEGs has obvious defects when being used for humidity sensing, and is mainly characterized by lower response voltage, limited sensitivity and slow response speed, and is difficult to meet the accurate and rapid humidity detection requirements. These problems are mainly due to one of the factors that the ability and speed of diffusion of water molecules in the sensing material is detrimental to the diffusion of the generated ion pairs, resulting in poor sensitivity and slow response speed. Secondly, the limited ionization capacity of water molecules cannot generate a sufficient number of positive and negative ion pairs, so that the potential difference at two ends of the device is smaller. Numerous researchers have developed a certain study to improve the sensing performance of humidity sensors based on microelectronic generators (MEGs), such as strategies of building functional group gradients, introducing hetero-functional structures, designing dry and wet areas, etc., aiming at enhancing humidity gradient differences inside the sensors and improving ion diffusion capacity, but also have certain defects, such as susceptibility to interference in actual dynamic humidity environments depending on the design of the dry and wet area differences or gradient structures, insufficient gradient stability, and poor repeatability of sensor output. The existing strategy has limited improvement degree of the ionization efficiency of the water, insufficient ion pair generation quantity, low output potential and sensitivity lifting amplitude, and difficulty in meeting the high-precision detection requirement. Therefore, how to construct a built-in electric field inside the self-powered sensor, to realize the synergistic effect of the electric field and the humidity gradient, and solve the core problems of slow ion diffusion and low ionization efficiency at the same time, becomes a key direction to be broken through in the current self-powered humidity sensing technology field. The electric field enhanced self-powered humidity sensor which has a simple structure and excellent performance and can be applied in a large scale is developed, and has important theoretical significance and engineering value for promoting the development of the Internet of things sensing technology and expanding the practical application of the self-powered sensor in multiple fields. Disclosure of Invention Aiming at the defects, the invention provides the electric field enhanced self-powered humidity sensor, the preparation method and the application thereof, and the high-efficiency humidity sensing performance of the humidity energy generator is improved by enhancing the internal electric field, so that the output voltage and the response speed of the sensor are obviously improved. The specific technical scheme is as follows: The electric field enhanced self-powered humidity sensor sequentially comprises an aluminum electrode layer, a filter paper middle layer and a copper electrode layer from top to bottom, wherein the copper electrode layer is completely overlapped with the lower surface of the filter paper middle layer, the aluminum electrode layer covers 60-80% of the upper surface area of the filter paper middle layer, 20-40% of the upper surface area of the filter paper middle layer is an exposed area, the aluminum electrode layer and the copper electrode layer form an asymmetric metal electrode, the filter paper middle layer is coated with a sensitive material, and the sensitive material is a potassium chloride modified h-C 3N4/PVA composite material. The humidity sensor provided by the invention adopts the h-C 3N4/PVA composite material mod