Preparation And Capacitive Properties Of Metal Oxides Based Composite Materials

From the decades of development of supercapacitors,electrode materials have been one of the most important factors affecting the performance of supercapacitors.Carbon materials,metal oxides,conducting polymers constitute the three major categories electrode materials of supercapacitors.However,all kinds of electrode materials have their advantages and disadvantages,if one material is used alone on supercapacitors,that will make the performance of supercapacitors defective,and difficult to meet people's needs.In this paper,MO_x-based composite materials were prepared,to optimize the overall performance of the material,so that it can play a better role in the supercapacitors.This paper mainly studies from the following four aspects:?1?Preparation of vanadium pentoxide?V₂O₅?sol by sol-gel method,graphene oxide?GO?was prepared by modified Hummers method,then add a small amount of ammonia for nitrogen doping,and nitrogen-doped graphene/vanadium pentoxide?N-rGO/V2O5?composite gels were prepared by hydrothermal method.Finally,the structures,morphology,electrochemical performance and other aspects were analyzed.?2?Nitrogen-doped carbon nanotubes/manganese dioxide?N-CNT/MnO₂?composites were synthesized by the polypyrrole tube was prepared by a template method,N-CNT were prepared by calcination,then potassium permanganate?KMnO₄?was added into it.The structure,morphology,electrochemical properties and other aspects were characterized.?3?The titanium dioxide?TiO₂?precursor was first prepared by sol-gel method,and the TiO₂ powder was obtained by calcination and grinding.Then,the polypyrrole?PPy?tube was prepared by a template method,and the TiO₂/PPy/rGO composite gel was prepared by hydrothermal method.Finally,its structure,morphology,electrochemical properties and other aspects were analyzed.?4?The pretreatment of the fresh lotus rod was carried out,and hydrothermal treatment of the treated lotus rod and KMnO₄,and then carbonized the product after hydrothermal to prepare the biomass carbon/manganese oxide?C/Mn3O4?composite materials.And finally its structure,morphology,electrochemical performance and other aspects were characterized.