Preparation And Properties Of Supercapacitor Electrode Materials And Enlightenment Of The Research Process In The Teaching Of High School Physics

Supercapacitor as a new energy storage device,with high power density,ultra-fast charge and discharge rate,long cycle life,environmental friendly and so on,draw public attentions widely.The electrode material is the core of the entire device for supercapacitor,which determines the performance of the energy device.So it is necessary to develop useful electrode materials for supecapacitor.Carbon-based materials,with good conductivity and high specific surface area,become the key material for the supercapacitor.Metal oxides were studied deeply by researchers due to the high theoretical specific capacitance.The combination of carbon-based materials and metal oxides show synergistic effect,which greatly promote the diversification and practicality of the electrode materials.And it promotes the energy density and power density of the supercapacitor.In this paper,we fabricated graphene oxide(GO)and hollow Fe2O3 nanotubes via modified Hummers method and hydrothermal method,respectively.Then we combined with the nitrogen doped graphene and hollow Fe2O3 nanotubes,synthesizing the nitrogen doped graphene and hollow Fe2O3 nanotubes composite materials(Fe2O3/NG).The specific capacitance of Fe2O3/NG electrode is 270 F/g(136 F/g for the graphene and hollow Fe2O3 nanotubes composite materials(Fe2O3/G))at a current density of 1 A/g.And the Fe2O3/NG electrode shows an excellent capacitance retention after 3000 cycles.These results revealed that the Fe2O3/NG electrode possesses a good electrochemical performance.In addition,we fabricated nitrogen doped graphene foam/carbon nanotube/manganese oxide(NGF/CNT/MnO2)ternary composite electrodes via chemical vapor deposition(CVD)and hydrothermal method.In comparison with the traditional fabricating electrode,in situ method is facial and decreases the contact resistance without binder.On one hand,NGF/CNT with high specific surface area,good conductivity acts as a supporter,which loads more active materials.On the other hand,MnO2 appeares as one of the most promising candidates due to its low cost,environmentally friendly and high theoretical capacitance in this ternary structure.We synthesized samples with different MnO2 mass loading by changing the concentration of the reaction.The morphology of the whole ternary structure was changed and the thickness of MnO2 nanosheet was adjusted effectively by changing the MnO2 mass loading.The specific capacitance of entire electrode of NGF/CNT/MnO2-70%sample is 284 F/g and areal capacitance is 3.03 F/cm2 at scan rate of 2 mV/s.What's more,the capacitance of the NGF/CNT/MnO2 composite electrodes show a 51.6%increase after 15000 cycles.So the novel ternary structure provide an effective designing strategy for the supercapacitor electrodes.Finally,through the research process of supercapacitor electrode materials,combined with my professional characteristics and internship experience in high school,we found that involved in the process of scientific research contents,research methods,design thinking and the basis of convey emotion manner values,both have close connection with the process of high school physics teaching.Therefore,such scientific research process is of great enlightenment to the physics teaching of high school.