Graphene Construction Porous Carbon And Its Composites In Supercapacitors

In the last decade there has been a great deal of interest in energy storage devices using graphene-based carbon materials（Graphene）.Graphene-based materials have great potential for energy storage applications due to their unique two-dimensional structure and inherent physical properties,such as good electrical conductivity and large specific surface area.The conversion of graphene-based materials into porous carbon has become a hot topic in carbon materials research in recent years.Porous carbon materials have gradually become available for a wide range of applications due to their large specific surface area and tunable pore size,which can be synthesised with different materials.These properties make porous carbon materials very promising for applications such as energy storage,water and gas purification,electrocatalysis and sensing.Given the scarcity of energy on earth and the increasing environmental problems,the search for new sustainable and environmentally friendly energy materials is of great importance.The combination of porous carbon materials with other materials for energy storage is therefore a research topic that is currently receiving much attention.This thesis firstly introduces the preparation of polypyrrole and nanoporous carbon composites:PVA-co-PE nanofibre suspensions are mixed with graphene oxide dispersions in a certain ratio,freeze-dried and then subjected to high temperature carbonisation to obtain nanoporous carbon materials,and a simultaneous polymerisation/composite reaction is carried out using the CTAB template method to uniformly coat the linear polypyrrole（PPy）on the porous carbon surface to obtain PPy The PPy@Porous carbon layered porous material was used as an electrode material for supercapacitors,and its morphological,structural and electrochemical properties were characterized.The composite material（PPy@Porous carbon）was tested at three electrodes and its mass specific capacitance was approximately 188 F/g at a current density of 1 A/g.Furthermore,the cycle efficiency of PPy@Porous carbon was maintained at 70%at a constant current charge/discharge of 1000 cycles at a current density of 1 A/g.And then this thesis introduces a KOH activated reduced graphene oxide（r GO）silk staple fibre（SF）composite porous carbon film was prepared by a simple vacuum filtration method and the film was used as a flexible electrode material for supercapacitors;1 mol/L of KOH solution was added to the silk staple fibre/graphene oxide mixture when the mass ratio of KOH to graphene oxide was 14:1 and the tube furnace sintering temperature was The KOH-activated reduced graphene oxide/silk staple fiber composite film was used as an electrode material for supercapacitors at a current density of 2 m A/cm²to provide an area specific capacitance of 2421.66 m F/cm²for further application by using 1 mol/L Na₂SO₄solution as the electrolyte.For further application,the all-solid-state symmetrical supercapacitor was assembled with a PVA-KOH solid electrolyte and achieved an area specific capacitance of 466.66 m F/cm²at a current density of 0.5 m A/cm²,while retaining91.7%capacitance after 5000 cycles of charging and discharging;the symmetrical supercapacitor was subjected to flexible electrical tests and exhibited similar good electrical properties when bent at 0°and 180°.The symmetrical supercapacitor showed similar good electrical properties when bent at 0°and 180°.