With the development of wearable smart devices and implantable medical devices, flexible batteries with high energy density, power density and long cycle life have become hotspots in recent years. Due to the unique structural advantages, two-dimensional materials have become ideal flexible electrodes. Materials. However, currently known two-dimensional electrode materials tend to have a dense atomic arrangement, which causes lithium ions to encounter large steric hindrance between layers, resulting in lower power density and energy density.
Recently, under the guidance of Li Yuliang, an academician of the Chinese Academy of Sciences, the carbon-based materials and energy application research group led by Huang Changshui, a researcher at the Qingdao Institute of Bioenergy and Process, Chinese Academy of Sciences, designed and synthesized a fluorine-substituted graphene two-dimensional carbon material for lithium-ion batteries. The negative electrode shows excellent electrochemical energy storage performance. Related results have been published online in Energy & Environmental Science.
The research team recently reported the preparation of graphene (Chemical Communications, 2018, 54, 6004) on different substrates, nitrogen-doped graphene (Carbon, 2018, 137, 442), graphene-containing iron (2D Materials, 2018, DOI) : 10.1088/2053-1583/aacba5). Researchers have successfully introduced fluorine atoms into the structure of graphene, and prepared new carbon-based flexible electrode materials, which will greatly promote the development of flexible batteries required for wearing smart devices. It is shown that, by fluorine substitution, the pores of the graphene alkene are enlarged, and the ion transport channel is also excellent under the AB accumulation; at the same time, the basic framework of the graphene and the conjugate system in the two-dimensional planar structure are retained, so that the material has Excellent conductivity and carrier transport characteristics; especially the fluorocarbon bond has excellent cyclic lithium storage capacity, which not only increases the lithium storage site of the material, but also has good compatibility between the carbon fluoride bond and the electrolyte. The interface impedance is greatly reduced, thereby improving the cycle stability. The research results provide a research idea for preparing a flexible electrode material with excellent large-area performance by solution method, and creating a new energy storage device. A new direction of research materials (Energy & Environmental Science, 2018, DOI: 10.1039 / C8EE01642A).
The research was supported by the National Natural Science Foundation of China, the Frontier Key Research Project of the Chinese Academy of Sciences, and the Outstanding Youth Fund of the Natural Science Foundation of Shandong Province.
Figure: Application of fluorine-substituted graphene in flexible batteries
