ACNFs@Ni-Mn-P nanosheet array composite material as well as preparation method and application thereof

Abstract

The invention discloses an ACNFs@Ni-Mn-P nanosheet array composite material which is prepared by the following steps of: by taking polyacrylonitrile, N, N-dimethylformamide, manganese acetate tetrahydrate, nickel acetate tetrahydrate, urea, ammonium fluoride and sodium hypophosphite as initial raw materials, firstly preparing a carbon nanofiber precursor through an electrostatic spinning method, then obtaining activated carbon nanofibers through low-temperature pre-carbonization, high-temperature carbonization and activation, and finally, carrying out hydrothermal reaction and calcining. The overall diameter is 6-7 microns. The thickness of the Ni-Mn-P nanosheets ranges from 30 nm to 40 nm, and the surfaces of the Ni-Mn-P nanosheets are rough. The preparation method comprises the following steps of: preparing a carbon nanofiber precursor; preparing and activating active carbon nanofibers; and preparing ACNFs@Ni-Mn-OH and the ACNFs@Ni-Mn-P. When the material is used as a supercapacitor electrode material, the material is charged and discharged within the range of 0-0.45 V. When the discharge current density is 1 A g <-1 >, the specific capacitance can reach 1000-1100 F g <-1 >; and when the discharge current density is 10A g <-1 >, the cycling stability after 5000 cycles is 88.53%, and the coulombic efficiency is 100%.

Description

technical field [0001] The invention relates to the technical field of supercapacitors, in particular to an ACNFs@Ni-Mn-P nanosheet array composite material and its preparation method and application. Background technique [0002] Supercapacitors (also known as electrochemical capacitors) have received more and more attention because of their high power density, fast charge-discharge process and long life, and are a better energy storage between traditional physical capacitors and batteries element. Most of the performance indicators of supercapacitors are determined by the electrode materials of its core components. At present, for supercapacitors, the specific capacitance, cycle stability and other performance issues of electrode materials are the focus of researchers. [0003] It is a common method to prepare supercapacitor electrode materials by synthesizing transitional double metal oxides. For example, in the prior art, Tian et al. grew Ni–Mn–O nanosheets directly on...

AI Technical Summary

Problems solved by technology

The experimental results show that the phosphating technology has successfully improved the electrochemical performance of the electrode material, but still cannot meet the application requirements

The reason is that NiCoP / C derived from Ni / Co-MOF has obvious stacking phenomenon on the microstructure, which directly leads to the covering of a large number of electrochemically active sites.

To solve this problem, the performance can be improved by controlling the microstructure of the composite material. Specifically, the material with a specific morphology can be prepared to prevent the collapse of the structure and improve the overall cycle stability of the material. It can be seen that the control of morphology by electrochemical deposition is a A feasible method, but the specific capacitance of the resulting material is extremely low

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