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CN-122025445-A - Polypyrrole-based integrated supercapacitor with energy storage and sensing functions and preparation method thereof

CN122025445ACN 122025445 ACN122025445 ACN 122025445ACN-122025445-A

Abstract

The invention discloses a polypyrrole-based integrated supercapacitor with energy storage and sensing functions and a preparation method thereof. The device is of a sandwich integrated structure and comprises a hydrogel electrolyte layer and polypyrrole-graphene oxide composite electrode layers which are grown on two sides of the hydrogel electrolyte layer in situ. According to the method, the electrode load is improved through repeated in-situ growth strategies, seamless strong interface combination of the electrode and the electrolyte is realized, and the graphene oxide can regulate polypyrrole to form a porous woven network structure. The device surface capacitance of the self-powered strain sensor reaches 928.1 mF cm ‑2 , the self-powered strain sensor can be used as the self-powered strain sensor without changing the structure, the response time is 0.2 s, the lowest detection pressure is 50 Pa, the physiological and motion signals of a human body can be accurately monitored, and the self-powered strain sensor is suitable for the fields of wearable electronics, health monitoring and the like.

Inventors

  • LI JIALE
  • XU BEN
  • LI BINGGANG
  • XIAO SHUYAO

Assignees

  • 中国石油大学(华东)

Dates

Publication Date
20260512
Application Date
20260319

Claims (10)

  1. 1. The polypyrrole-based integrated supercapacitor with the energy storage and sensing functions is characterized by being of a sandwich integrated structure and comprising a hydrogel electrolyte layer and polypyrrole-graphene oxide (PPy-GO) composite electrode layers symmetrically grown on two sides of the hydrogel electrolyte layer, wherein the PPy-GO composite electrode layers and the hydrogel electrolyte layer form a strong-combination integrated structure without an interfacial gap through repeated in-situ oxidation polymerization strategies, and the device has the electrochemical energy storage function of the flexible supercapacitor and the physiological signal and human motion monitoring function of a self-powered strain sensor.
  2. 2. The device of claim 1, wherein the hydrogel electrolyte layer is a polyvinyl alcohol-sodium alginate composite hydrogel, and the composite hydrogel is doped with a molybdenum disulfide nanosheet and sulfuric acid-polyethylene glycol electrolyte system, and the preparation raw materials of the hydrogel electrolyte layer comprise, by weight, 18 parts of deionized water, 0.95 part of 98% concentrated sulfuric acid, 3 parts of polyethylene glycol with a polymerization degree of 200, 0.15 parts of sodium alginate, 0.05 part of molybdenum disulfide, and 3 parts of polyvinyl alcohol with a polymerization degree of 210 and an alcoholysis degree of 99%.
  3. 3. The device according to claim 1, wherein the device is used as a self-powered strain sensor, an external power supply is not needed, strain signal detection is realized through self-output current change, response time and recovery time are 0.2 s, the lowest detection pressure reaches 50 Pa, and real-time monitoring of human physiological signals and limb movements can be realized.
  4. 4. The device of claim 3, wherein the physiological signal comprises facial expression, respiration, swallowing, vocal cord vibration while speaking, radial artery pulse, brachial artery pulse, and the limb movement comprises joint bending, plantar pressure changes.
  5. 5. The device according to claim 1, wherein a titanium foil current collector is further arranged on the outer side of the PPy-GO composite electrode layer, the whole device is sealed through silica gel, when the device is used as a self-powered strain sensor, the outer side of the device is packaged with a polyethylene terephthalate tape through a polyethylene protective film, and the electrode layer leads out a signal wire through a copper foil.
  6. 6. The preparation method of the polypyrrole-based full-gel integrated device with the energy storage and sensing functions is characterized by comprising the following steps of: S1, preparing a hydrogel electrolyte, namely adding sulfuric acid and polyethylene glycol into deionized water, sequentially adding sodium alginate, molybdenum disulfide and polyvinyl alcohol, mechanically stirring at 95 ℃ until the sodium alginate, the molybdenum disulfide and the polyvinyl alcohol are completely dissolved, pouring the obtained solution into a mold, and performing constant temperature and constant humidity air drying after low temperature freezing to obtain the hydrogel electrolyte; S2, repeatedly performing in-situ polymerization to prepare a composite electrode, namely immersing the hydrogel electrolyte obtained in the step S1 into pyrrole monomers for pre-soaking, transferring the hydrogel electrolyte into dispersion liquid containing ferric trichloride and graphene oxide, and performing in-situ oxidative polymerization under the ice bath condition to complete one growth cycle; And S3, post-treatment, namely standing the integrated precursor obtained in the step S2, immersing the integrated precursor into electrolyte solution for activation, and trimming the edge to obtain the polypyrrole-based full-gel integrated device.
  7. 7. The preparation method of the ice bath according to claim 6, wherein in the step S2, the pre-soaking time of the pyrrole monomer in the first growth cycle is 25min, the in-situ oxidation polymerization time is 25min, the pre-soaking time of the pyrrole monomer in the subsequent repeated growth cycle is 10min, the in-situ oxidation polymerization time is 25min, and the temperature of the ice bath condition is 0-4 ℃.
  8. 8. The method according to claim 6, wherein in the step S2, the concentration of the ferric trichloride is 0.5 mol.L-1, the concentration of the graphene oxide is 3 mg.mL-1, and the number of repetitions of the growth cycle is 3.
  9. 9. The method according to claim 6, wherein in the step S3, the standing time is 8 hours, the electrolyte solution is 1 mol.L-1 sulfuric acid solution or 1 mol.L-1 sodium chloride solution, and the activation impregnation time is 6 hours.
  10. 10. The method for manufacturing the self-powered strain sensor according to claim 6, further comprising the step S4 of packaging the sensor, wherein the electrodes on the two sides of the device obtained in the step S3 are led out through copper foil wires, the upper surface and the lower surface of the device are covered by polyethylene protective films, and edges are sealed and fixed through polyethylene terephthalate adhesive tapes, so that the self-powered strain sensor is packaged.

Description

Polypyrrole-based integrated supercapacitor with energy storage and sensing functions and preparation method thereof Technical Field The invention relates to the technical field of capacitor material preparation, in particular to a polypyrrole-based integrated supercapacitor with energy storage and sensing functions, and also relates to a preparation method of the supercapacitor. Background With the rapid development of flexible wearable electronic equipment in the fields of health monitoring, man-machine interaction, soft robots and the like, the technical requirements of light weight, high flexibility and high power density are provided for matched energy devices. The flexible super capacitor is used as a novel electrochemical energy storage device, and becomes a research hot spot in the field of flexible electronics by virtue of the core advantages. Meanwhile, developing an integrated device integrating energy storage and sensing is an important development direction of the next generation wearable electronic system. Currently, a hydrogel supercapacitor with a sandwich structure is a mainstream structure of a flexible energy storage device, and through the combination of an external conductive electrode layer and an internal ion conduction hydrogel electrolyte, the hydrogel supercapacitor realizes the cooperative transmission of electrons and ions and has an integrated structure and excellent strain tolerance characteristics. However, the device has core bottlenecks in practical application, namely firstly, the interface combination of an electrode and an electrolyte is weak, the adhesion between the electrode and the electrolyte of the traditional stacked design is weak, interlayer sliding and electrode separation are easy to occur under the deformation of repeated bending, torsion and the like, so that contact resistance is suddenly increased, the electrochemical performance and long-term circulation stability of the device are greatly attenuated, secondly, the electrochemical performance and mechanical flexibility are inherently balanced, when the active material loading of a conductive polymer is improved for improving the energy density, the brittleness of an electrode layer is often increased, an ion diffusion channel is blocked, the mechanical flexibility of the device is damaged, the multiplying power performance is greatly reduced, and thirdly, the existing research is mostly difficult to realize the functional integration of energy storage and sensing, and a few integrated devices have the problems of low sensing sensitivity, slow response speed and poor signal stability. In the prior art, although related researches for improving interface bonding through an in-situ polymerization strategy exist, the core problems that polypyrrole conductive polymers are easy to agglomerate into particles and the microcosmic morphology is uncontrollable cannot be solved, so that the utilization rate of electrode active sites is low, meanwhile, the loading of electrode materials and excellent electrochemical performance are difficult to be considered, and the synergistic unification of high-performance energy storage and high-sensitivity sensing cannot be realized. Therefore, the integrated supercapacitor with firm interface, excellent electrochemical performance, good mechanical flexibility and high sensitive sensing capability is developed, and the integrated supercapacitor has important scientific research value and industrial application prospect. Disclosure of Invention The invention aims to provide a polypyrrole-based integrated supercapacitor with energy storage and sensing functions and a preparation method thereof, and the device has excellent electrochemical energy storage performance and self-powered strain sensing performance and realizes high integration of the energy storage and sensing functions. In order to achieve the above object, the present invention is implemented by the steps of: step 1, heating raw materials by using an one-pot oil bath to obtain a mixed solution; step 2, cooling and placing to obtain hydrogel, and cutting into proper shapes according to the requirement; Step3, soaking the hydrogel in pyrrole and ferric chloride/graphene oxide solution in sequence to initiate polymerization reaction, repeatedly soaking the pyrrole and ferric chloride/graphene oxide solution for repeated growth, and then growing an electrode material layer on the surface of the hydrogel; Step 4, cutting out the peripheral edges after growing the electrode material to obtain the polypyrrole-based integrated supercapacitor with the functions of energy storage and flexible sensing; And 5, packaging the device. The invention has the following beneficial technical effects: 1. According to the invention, through repeating the in-situ oxidation polymerization strategy, the polypyrrole/graphene oxide composite electrode is directly grown on the surface of the hydrogel electrolyte, so that the seamless integrated c