CN-121983432-A - Graphene doped polypyrrole/silver ruthenium alloy composite electrode for flexible supercapacitor and preparation and application thereof

Abstract

The invention discloses a graphene doped polypyrrole/silver ruthenium alloy composite electrode for a flexible supercapacitor and preparation and application thereof, and belongs to the technical field of supercapacitors. The composite electrode constructs a multi-level interface enhancement system of an inorganic conductive layer, an organic active layer and a flexible substrate, improves the adhesive force of a metal layer through dopamine bionic modification, and innovates a synergistic action mechanism of rGO and PPy. During preparation, the substrate is modified by dopamine to enhance the bonding strength, a silver-ruthenium alloy layer is sputtered to construct a charge transmission channel, electrochemical codeposition and reduction are carried out to form a three-dimensional conductive network, a low-temperature wet method is adopted to avoid thermal deformation, and an environment-friendly reducing agent is adopted to ensure biocompatibility. Parameters are optimized by stage sputtering, and ascorbic acid is reduced and compounded stably. In application, the flexible supercapacitor prepared by taking the composite electrode as a core has high energy density, flexibility and long cycle life after activation, and meets the requirements of wearable equipment.

Inventors

• ZHANG LISONG
• ZHUANG YANG
• QIAO XIAOJUN
• LIU YUNFENG
• LIU LICHAO
• LIU YIBO
• ZHANG BAOLI
• Zhang Zaisu
• QU YONGSHENG
• ZHAO LEI
• CHU HONGGUO
• WU PENGYUE
• WANG XIAOHUI
• HE TING
• CHEN SI
• Lou Fangxi
• Dai Benqian
• Gao Yushuan
• SUN GUOHUI

Assignees

• 西安热工研究院有限公司
• 华能伊敏煤电有限责任公司

Dates

Publication Date

20260505

Application Date

20260204

Claims (10)

1. 1. The graphene doped polypyrrole/silver ruthenium alloy composite electrode for the flexible supercapacitor is characterized by sequentially comprising a substrate, a dopamine modification layer modified on the surface of the substrate and a composite deposition layer positioned on the dopamine modification layer from bottom to top; The composite deposition layer comprises a silver-ruthenium alloy sputtering layer and an electrochemical deposition layer positioned on the silver-ruthenium alloy sputtering layer, and the electrochemical deposition layer is of a composite structure of reduced graphene oxide and polypyrrole.
2. 2. The graphene-doped polypyrrole/silver-ruthenium alloy composite electrode for a flexible supercapacitor according to claim 1, wherein the substrate is polyetheretherketone or polyvinylidene fluoride.
3. 3. The preparation method of the graphene doped polypyrrole/silver ruthenium alloy composite electrode for the flexible supercapacitor as claimed in claim 1 or 2, which is characterized by comprising the following steps: step 1, carrying out dopamine modification on a pretreated substrate to obtain a dopamine-modified substrate; step 2, sputtering and depositing a silver ruthenium alloy layer on the dopamine-modified substrate; And 3, taking the substrate deposited with the silver ruthenium alloy layer as a working electrode, carrying out electrochemical deposition to form a substrate deposited with the graphene oxide and polypyrrole layer, immersing the substrate into an ascorbic acid solution, carrying out reduction treatment, washing and vacuum drying to obtain the electrode of the reduced graphene oxide/polypyrrole composite layer.
4. 4. The preparation method of the graphene doped polypyrrole/silver ruthenium alloy composite electrode for the flexible supercapacitor according to claim 3 is characterized by comprising the following steps of specifically immersing a pretreated substrate in a dopamine hydrochloric acid solution, cleaning and drying to obtain a dopamine modified substrate, wherein the concentration of the dopamine hydrochloric acid solution is 1-3 g/L, the immersion temperature is 25-35 ℃, and the rotation speed is 100-200 r/min and oscillation is carried out for 5-7 h.
5. 5. The method for preparing the graphene-doped polypyrrole/silver-ruthenium alloy composite electrode for the flexible supercapacitor according to claim 3, wherein in the step 2, sputtering comprises pre-sputtering and sputtering, wherein the pre-sputtering vacuum degree is 4×10 -3 Pa, the argon flow is 10-20 sccm, the sputtering power is 50-70W, the pre-sputtering time is 5-15 min, the sputtering vacuum degree is 2×10 -3 Pa, the argon flow is 15-25 sccm, the sputtering power is 100-200W, and the single-side deposition time is 80-100 s.
6. 6. The preparation method of the graphene-doped polypyrrole/silver-ruthenium alloy composite electrode for the flexible supercapacitor according to claim 3, wherein in the step 3, the electrochemical deposition solution contains 0.2mol/L pyrrole monomer, 0.08mol/L sodium dodecyl benzene sulfonate and 0.02g/L graphene oxide, the electrochemical deposition potential is 0.7-0.9V, the temperature is 25-35 ℃, and the constant voltage and constant potential are deposited for 250-350 s.
7. 7. The method for preparing the graphene-doped polypyrrole/silver-ruthenium alloy composite electrode for the flexible supercapacitor according to claim 3, wherein in the step 3, the concentration of the ascorbic acid solution is 0.1-0.2 mol/L, the reduction temperature is 40-60 ℃, and the reduction time is 1-2 h.
8. 8. The use of a graphene doped polypyrrole/silver ruthenium alloy composite electrode for a flexible supercapacitor according to claim 1 or2 for preparing a flexible supercapacitor.
9. 9. A flexible supercapacitor comprising as a working electrode a graphene-doped polypyrrole/silver ruthenium alloy composite electrode as claimed in claim 1 or 2 after activation.
10. 10. The flexible supercapacitor according to claim 9, wherein the activation treatment comprises 40 to 60 cycles of cyclic voltammetric activation in an electrolyte at a sweep rate of-0.6 to 0.8v vs. Ag/AgCl, 100 to 200 mV/s, followed by annealing at 70 to 90 ℃ for 50 to 70 minutes under nitrogen atmosphere.

Description

Graphene doped polypyrrole/silver ruthenium alloy composite electrode for flexible supercapacitor and preparation and application thereof Technical Field The invention belongs to the technical field of supercapacitors, and particularly relates to a graphene doped polypyrrole/silver ruthenium alloy composite electrode for a flexible supercapacitor, and preparation and application thereof. Background The flexible super capacitor is used as an energy storage device with great potential, takes a central position in the front fields of wearable electronics, flexible display and the like by virtue of the unique advantages of small volume, quick charge and discharge, flexible folding and the like, and the performance of the flexible super capacitor is highly dependent on the synergistic optimization effect of electrode materials and a preparation process. In the current commercial supercapacitor electrode materials, polypyrrole (PPy) is widely paid attention to due to the advantages of low preparation cost, high electrochemical activity, environmental friendliness and the like. However, the inherent defects of polypyrrole severely restrict the application of the polypyrrole in wider scenes, namely the conductivity of a pure PPy molecular chain is poor, the conductivity is generally lower than 70S/cm, the interface resistance problem is easily caused by the low conductivity in the charge transmission process, the overall performance of an electrode is further influenced, the PPy chain can expand and contract by 15% -20% in volume during charge and discharge, an active layer is easily fallen off due to the volume change after long-term cyclic use, and the capacitance retention rate is very lower than 80% after 5000 cycles, so that the practical requirement of long-life use is difficult to meet. In order to improve the performance of the PPy, the prior art mostly adopts a mode of adding carbon materials (such as carbon nano tubes and graphene) to construct a composite system, but the scheme has obvious limitations that the interface compatibility of the carbon materials and the PPy is poor, agglomerates are easily formed due to uneven dispersion in the mixing process, the agglomerates cannot exert the expected enhancement effect, but block an ion transmission channel to cause the specific capacitance of a composite electrode not to rise and fall, and part of the scheme adopts toxic surfactants (such as sodium dodecyl sulfate) to promote the dispersibility, however, the residual reagents pollute electrolyte and reduce the safety of devices, and the biocompatibility of a flexible substrate is damaged, so that the electrode material is not suitable for wearable equipment close to human bodies, and the problem of bonding between a conductive layer of the flexible electrode and the substrate is not solved effectively. The traditional metal layers (such as Cu and Sn) prepared by a magnetron sputtering process and polymer substrates (such as PVDF and PET) are only in physical attachment, the interfacial bonding force is less than 0.5N/cm, and after 1000 times of bending, the capacitance attenuation is more than 30 percent, so that the metal layers cannot bear the mechanical stress faced by a long-term flexible use scene. In addition, the existing preparation process has the defects in the aspects of greenization and economy that most schemes need high-temperature treatment (150-200 ℃) to enhance the bonding strength of materials, the process not only increases energy consumption, but also easily causes thermal deformation of a flexible substrate to influence the overall performance of an electrode, and part of electrochemical polymerization process depends on high-concentration strong acid electrolyte, is complex in subsequent treatment and easy to corrode equipment, and is difficult in large-scale production. Along with the development of wearable electronic equipment to high power density (> 1 kW/kg), long cycle life (> 10000 times) and green environmental protection, a flexible electrode material which has high conductivity, strong flexibility and excellent cycle stability and simple and environment-friendly preparation process is developed, and the flexible electrode material has become a key requirement for breaking through the performance bottleneck of a flexible supercapacitor and pushing industrial development. Disclosure of Invention Aiming at the problems of insufficient conductivity, poor mechanical flexibility and weak cycling stability of the polypyrrole-based electrode in the prior art, the invention aims to provide a graphene doped polypyrrole/silver ruthenium alloy composite electrode for a flexible supercapacitor, and preparation and application thereof. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: The invention provides a graphene doped polypyrrole/silver ruthenium alloy composite electrode for a flexible supercapacitor, which sequentially com