Flexible Porous Carbon Membrane From Core-shell Unimicelles For Electrochemical Energy Storage

Flexible porous carbon membrane is a kind of self-supporting electrode material,which is an important part of “wearable” devices.It has great application prospects in the fields of robotics and health monitoring.At present,polymers have high elastic deformation and viscoelasticity,and polymers as precursors facilitate the preparation of self-supporting polymer films.At the same time,rich polymer synthesis methods can control polymer materials with different molecular weights,molecular weight distributions and topologies.When the porous carbon material is prepared by cross-linking and pyrolysis reaction,the block ratio of the polymer segment of the block polymer can be controlled,and the multi-stage microporous/mesoporous nanostructure of the porous carbon can be rationally designed and adjusted.Thereby increasing the specific surface area of the porous material facilitates the transport of the electrolyte and charge within the material.In this thesis,self-supporting polymer membranes were prepared by electrospinning of single-molecular polymer micelles with core-shell structure,and self-supporting porous carbon membranes with multi-stage pore structure were prepared by high-temperature carbonization,and used as electrode materials for electrochemical energy storage.The main research contents are as follows: 1.Star-shaped polyester H40-star-polyacrylonitrile block copolymer(H40-star-PAN)was prepared by reversible addition-fragmentation chain transfer polymerization with hyperbranched polyester H40 as macroinitiator.It has good electrospinning,high carbonization yield,high specific surface area and electrical conductivity.The structure of the star-shaped block copolymer was characterized by nuclear magnetic resonance(NMR),infrared spectroscopy(FTIR)and gel permeation chromatography(GPC).The self-supporting polymer film was obtained by electrospinning,and the flexible porous carbon film was prepared by cross-linking and carbonization,and its morphology was analyzed.In view of the high stability of single-molecule polymer micelles,the porous carbon film has a high specific surface area and a multi-stage microporous/mesoporous structure,which can be applied to flexible solid supercapacitors,and explores the carbonization temperature for carbon material structure and capacitor performance.Impact.2.Preparation of star-shaped polyester H40-star-(poly(tert-butyl acrylate-b-polyacrylonitrile)block copolymer by hyper-branched polyester H40 as macroinitiator and reversible addition-fragmentation chain transfer two-step polymerization(H40-star-(Pt BA-b-PAN)).The structure of the star-shaped block copolymer was characterized by nuclear magnetic resonance(NMR)and infrared spectroscopy(FTIR).A star-shaped polyester H40-b-polyacrylic acid-bpolypropylene block copolymer was obtained by reaction with trifluoroacetic acid.The titanium dioxide precursor is selectively adsorbed to the inner layer of the polymer by electrostatic interaction.A titania@porous carbon film material having a core-shell structure is prepared by standing and carbonizing.In view of the strong interaction of titanium dioxide on polysulfides,the polysulfide is dissolved in the electrolyte,thereby achieving high capacity and stable cycle performance of the solid lithium-sulfur battery.