Magnetic cellular porous carbon nanometer fiber@carbon nanotube composite material prepared by carbonization & magnetization & vapor deposition

Abstract

The invention relates to a magnetic cellular porous carbon nanometer fiber@carbon nanotube composite material prepared by high-temperature carbonization & magnetization & vapor deposition for a lithium-sulfur battery positive electrode material. The method comprises the following steps of uniformly mixing aqueous emulsion containing polyvinyl alcohol and polytetrafluoroethylene and a small amountof boric acid, adding a certain mass of iron salt or ferrite to prepare a spinning solution, spinning to form a fiber under a joint effect of a high-voltage electrostatic field and high-speed air flow, performing low-temperature pre-processing under an air atmosphere, and further performing high-temperature carbonization & magnetization & chemical vapor deposition to obtain the magnetic cellular porous carbon nanometer fiber@carbon nanotube composite material. The magnetic cellular porous carbon nanometer fiber@carbon nanotube composite material prepared by the method is large in specific area, good in magnetism and high in bonding capability of materials, carbonization and growth (chemical vapor deposition) of a carbon nanotube are simultaneously achieved during the carbonization process,the preparation method is simple and practical and is good in controllability, and mass production can be achieved.

Description

technical field [0001] The present invention relates to a one-step high-temperature carbonization & magnetization & chemical vapor deposition method to prepare magnetic honeycomb porous carbon nanofiber@carbon nanotube composite material for lithium-sulfur battery positive electrode materials, especially to provide a kind of composite material with through holes and controllable pore size structure. On the carbon nanofiber matrix, carbon nanotubes are uniformly grown and loaded with ferrous fluoride and iron, with large specific surface area, strong bonding ability between materials, good magnetism, good conductivity, simple and easy to implement, environment-friendly, A method for preparing a mass-producible magnetic honeycomb porous carbon nanofiber@carbon nanotube composite material. Among them, the rich through-hole structure of the honeycomb carbon nanofiber matrix can effectively increase the sulfur storage, and the uniform growth of carbon nanotubes and uniform distribu...

AI Technical Summary

Problems solved by technology

However, part of the carbon nanotubes in the composite carbon material obtained by the doping of the former spinning solution is distributed inside the porous carbon nanofiber matrix, which cannot provide specific surface area and activity; while the physical doping uniformity of the latter cannot be guaranteed.

Kong et al. (Yuxia Kong, Tingting Qiu, Jun Qiu. Fabrication of novel micro-nano carbonous composites based on self-made hollow activated carbon fibers[J]. Applied Surface Science 265(2013) 352-357) used chemical vapor deposition to Carbon nanotubes are grown on a porous carbon fiber matrix, but the porous carbon fiber matrix must be prepared in advance, and the growth of carbon nanotubes can only be realized after secondary treatment, especially the proportional introduction of various reaction gases is difficult to control, the process is complicated, and the operation is difficult. , making its development into a bottleneck

Therefore, the preparation of composite carbon materials with large specific surface area, good uniformity, strong bonding ability between materials, and the preparation method is simple and easy to operate, good controllability, and can achieve large-scale production remains to be explored.

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