The Synthesis Of ZIFs Derived Supercapacitor Electrode Materials And Its Electrochemistry Performance

Supercapacitor is a kind of capacitor with high efficiency,new model and eco-friendly characteristics.It is widely used in various fields due to its excellent power density,fast charge and discharge,long service life,wide range of operating temperature,etc..Electrode material is one of the main factors affecting the performance of supercapacitors.Metal organic frameworks(MOFs)have adjustable pores,diverse structures and high specific surface areas,so they are considered to be one of the most promising electrode materials in the field of supercapacitors.In order to obtain supercapacitors with better performance,researchers have conducted extensive research on electrode materials.Among them,MOFs-derived materials are often used as templates because they can maintain the inherent characteristics of the original MOFs,such as morphology,large specific surface area and uniform pores.MOFs have derived various energy storage materials and are widely used in fields such as batteries and supercapacitors.Among the many MOFs,zeolite-like imidazole framework materials(ZIF,MOFs subclass)are considered to be one of the most promising precursors.In summary,this article uses ZIF-67 as the precursor to prepare binary and ternary composite materials and conduct electrochemical performance research.The main content is divided into two parts:In the first part,the PPy/ZIF-67 precursor is prepared from the zeolite-like imidazole framework material(ZIF-67)and polypyrrole nanotubes(PPy),and then under hydrothermal conditions,the binary composite PPy/Ni-Co LDH with a layered hollow structure was successfully prepared by adjusting the mass of the polypyrrole nanotubes(PPy)and ZIF-67.The PPy/Ni-Co LDH material was characterized,and Ni-Co LDH(nickel-cobalt double hydroxide)was tightly anchored on the outer surface of polypyrrole nanotubes(PPy).In addition,the electrochemical results show that as the mass of Ni-Co LDH increases,more active sites can be exposed,the chance of contact between electrolyte ions and active materials is increased,the migration path of electrolyte ions is shortened and their diffusion is accelerated,so that The electrochemical performance of PPy/Ni-Co LDH is getting better and better.The optimized sample shows a specific capacitance of 13.0 F cm^-2(1858.3 F g^-1)at 1 mA cm^-2,and has a good Magnification performance.In addition,a symmetrical hybrid supercapacitor based on the best sample was fabricated and showed an energy density of 10.43 m Wh cm^-2at a power density of0.25 m W cm^-2.In the second part,the hollow structure precursor Fe₃O₄@PPy-ZIF-67 was prepared by adding hollow Fe₃O₄microspheres,and then under hydrothermal conditions,the ternary composite material Fe₃O₄@PPy-NiCo-LDH with hollow structurewas prepared by hydrothermal method by adjusting the mass ratio of PPy and ZIF-67.And firstly,the Fe₃O₄@PPy-NiCo-LDH material was characterized,and the material can maintain a good hollow microsphere structure.Then the prepared Fe₃O₄@PPy-NiCo-LDH electrode material was tested for electrochemical performance.The test results show that Fe₃O₄@PPy-NiCo-LDH electrode material has good electrochemical performance,and its specific capacity is 438.6 F g^-1under 1 mA cm^-2.