The Controllable Preparation And Applications Of Graphene Fibers

Graphene possess a great application potentials in our production and daily life owing to its special structure and outstanding chemical and physics properties.For different requirements and applications,graphene had been assembled into three-dimensional blocks,two-dimensional films and one-dimensional graphene fibers.Although the demand for wearable products is increasing,it still is a challenging task for researchers to assemble graphene into fiber to take advantage of the graphene materials.So in this paper,we studied on the fabrication of graphene and the application of graphene fibers and got following conclusions.Firstly,graphene oxide（GO）had been successfully prepared by using the modified Hummers method,and graphene fibers was got though wed-spinning,chemical reduction.By changing the parameters to get different kinds of spiral graphene fibers.When the spiral graphene fiber with P=2mm,D=6mm was subjected to a force of 0.8mN,it elongated 320% showing excellent soft properties.Thus,it can be used to detect faint objects by the tactful optical design.It also can be used in the electrostatic field because of the elongation that caused by the electrostatic repulsion between the rolls of the spiral graphene fibers.At the same time,it has electromagnetic shielding effect with a microscopic spiral structure.Secondly,the spiral graphene/TiO₂ composite fiber was successfully fabricated by using surface modification technology.Its morphology,optical response and cycle stability had been characterized by SEM,XRD,Raman and electrochemical workstation.The results showed that TiO₂ had been successfully coated on the surface of spiral graphene fiber.The composite fiber showed a maximum photocurrent with the100 nm thickness of TiO₂ and the photocurrent remained unchanged after 200 cycle times.The composite fibers had a good response to the liquid vibration due to the increased irradiation area after stretching.At the same time,the composite fibers can be used to degrade organic pollutants.Thus,the chemical energy of the organic pollution can be converted to electrical energy.Thirdly,the graphene/TiO₂ fiber was successfully fabricated by wet-spinning of different proportions of TiO₂ and graphene oxide and 450 ℃ thermal reduction.Itshowed good flexibility and photoelectric properties at 50% content of TiO₂.There was a good combination between TiO₂ and graphene sheets,which was certificated by no changed photocurrent before and after ultrasonic.In order to expose the wrapped TiO₂,oxygen plasma etching method has been taken.The corresponding photoelectric current has increased with the extent of etching time.Finally,the energy storage fibers were got by a simple physical packaged the octadecane using the graphene oxide from anthracite.The results showed the phase change energy storage fibers could store more latent heat with the increasing of n-octadecane content.The amount of n-octadecane can be up to 90% and only 14%weight lost after 50 cycles.The energy storage fibers can be wove into flexible cloth with a good heat preservation effect.