Preparation method of graphene/phenylenediamine flexible composite film electrode

Abstract

The invention provides a preparation method of a graphene / phenylenediamine flexible composite film electrode. The preparation method comprises the following steps: (1) preparing a graphene oxide aqueous solution according to an improved Hummers method; (2) under the ultrasonic condition, uniformly mixing the graphene oxide aqueous solution with urea according to a mass ratio of graphene oxide, theurea and phenylenediamine of 1: (1 to 8): (1 to 3.5); slowly dropwise adding the a phenylenediamine aqueous solution into the mixed solution to enable the concentration of the graphene oxide aqueoussolution in the system to be 2 to 7 mg / mL, and pouring the solution into a container for drying, thus obtaining a graphene oxide / phenylenediamine / urea composite film; and (3) soaking the composite film in HI, washing the composite film, and heating the film at low temperature to obtain the graphene / phenylenediamine flexible composite film electrode. According to the preparation method, the urea and the graphene oxide are ultrasonically uniformly mixed at first so as to effectively avoid agglomeration and stacking of the graphene oxide due to graphene oxide solidification induced by phenylenediamine molecules within short time, and the capacitance performance of the flexible composite film electrode can be effectively improved.

Description

technical field [0001] The invention relates to the preparation of membrane electrode materials, in particular to a preparation method of graphene / phenylenediamine flexible composite membrane electrodes. Background technique [0002] After the oil crisis occurred in the 1970s, energy shortage has become a huge challenge facing human society. Solving the efficient use of energy and developing new clean energy has become a major concern of the world today. In recent years, high-efficiency energy storage devices have attracted widespread attention of researchers. Electrochemical capacitors, also called supercapacitors, have the advantages of high energy storage efficiency, long service life, environmental friendliness, safety and reliability, and have become a new type of energy storage element that has attracted much attention. In particular, as consumer electronics products are developing towards miniaturization, flexible foldable and wearable, the development of flexible el...

AI Technical Summary

Problems solved by technology

Although the introduction of phenylenediamine molecules into graphene significantly increases the specific capacitance of the composite material at low current densities, the capacitance performance of graphene composite electrode materials functionalized with phenylenediamine molecules is far lower than the theoretical value.

The main reason is that a small amount of phenylenediamine molecules are in contact with the graphene precursor graphene oxide solution, and in a short period of time, it is easy to cause graphene oxide to solidify, resulting in the agglomeration of the prepared graphene and the formation of close-packed particles. On the one hand, it affects the full utilization of the effective specific surface area of ​​graphene, so that the transport of electrolyte ions in the internal pores of the composite membrane electrode material is limited by diffusion kinetics; on the other hand, it affects the effective recombination of phenylenediamine and graphene. The reason why the capacitance performance of the prepared phenylenediamine composite flexible composite membrane electrode is lower than the theoretical value

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