Method for constructing flexible super capacitor

Abstract

The invention provides a method for constructing a flexible super capacitor. The method comprises the following steps: adding graphite oxide in deionized water according to a mass ratio of the graphite oxide to the deionized water of 0.5-2: 1000, and magnetically stirring or manually shaking for 0.5-1h to obtain a product A; stewing the product A at a temperature of 60-80 DEG C for 0.5-1h until a complete graphite oxide film is formed on the surface of graphite oxide hydrosol to obtain a product B; using a flexible film as a substrate, depositing the product B on the substrate, and drying to obtain a product C; soaking the product C in a hydrogen iodide solution with a mass percent of 55-85%, reducing for 3-48h at 15-80 DEG C, and cleaning to obtain a product D; and soaking the product D in 0.5-5mM potassium permanganate for 5-48h, and cleaning to obtain a product E, namely a graphene/manganite composite film deposited on the flexible substrate is obtained. The capacitor constructed by the method is good in electrochemical performance, and a traditional sandwich type flexible super capacitor can also be constructed, and meanwhile, the method is beneficial for the miniaturization and lighting and thinning of devices.

Description

technical field [0001] The invention relates to a construction method of a graphene-based flexible supercapacitor, in particular to a construction method of a planar graphene-based thin film supercapacitor based on a gas-liquid interface assembly method. Background technique [0002] Due to the development of wearable electronic devices, people's requirements for flexible energy storage devices are gradually increasing, and flexible supercapacitors have also attracted much attention. Among them, flexible supercapacitors based on two-dimensional thin film electrodes are particularly attractive for their light weight, miniaturization, and bendability. Graphene is a two-dimensional nano-carbon material, and its carbon atoms are sp 2 The hybridization method forms a six-membered ring honeycomb planar structure, which has ultra-high electron mobility (200,000cm 2 / V.s), large specific surface area (2630m 2 / g), good thermal conductivity (5300W / mK), and excellent mechanical str...

AI Technical Summary

Problems solved by technology

(J.J.Yoo, K.Balakrishnan, J.Huang, etal.NanoLetters2011,11,(4),1423-1427.) However, the layer-by-layer self-assembly of graphene films usually requires the use of positively charged nanomaterials and negatively charged nanomaterials. The graphene oxide solution is used as a precursor, and the substrate is repeatedly immersed in the two nanomaterial solutions in a cycle of immersion-cleaning-drying by using the electrostatic interaction between the two until the required film thickness is reached. The layer-by-layer self-assembly process is quite time-consuming and complicated, and the obtained graphene film is often a composite film; although the chemical vapor deposition process has significant advantages in the preparation of pure graphene films, its preparation process involves high temperature and high heat. process, and it is difficult to realize the controllable preparation of graphene-based composite films in one step

The two commonly used methods for preparing graphene-based films discussed above, the most critical problem is that the graphene films prepared by the two methods are directly deposited on the hard substrate, which cannot be directly applied to flexible supercapacitors. Complicated substrate transfer steps are required to transfer the prepared graphene-based film onto a flexible substrate. However, the transfer step of transferring the film from a rigid substrate to a flexible substrate usually requires the use of strong corrosive reagents to remove the hard substrate. The matrix is ​​dissolved, and the whole process is very time-consuming, consumable, and not environmentally friendly.