Theoretical Study On The Energy Storage Materials For Flexible Supercapacitor

As a new type of energy storage device that matches with flexible electronic devices,flexible supercapacitors have attracted wide attention.However,due to the low energy density of supercapacitors,it has limited its wide application and industrialization.Because the electrode is the main component of the flexible supercapacitor,the performance of the electrode material greatly affects the performance of the flexible supercapacitor.The related research of the reported flexible supercapacitor shows that the main research direction of the electrode material is the nanoization and compounding of the active material,and the research on the doped modified electrode material has also made great progress.And the study of its physical mechanism is also not deep enough.Therefore,this paper uses the combination of theoretical calculation and experimental verification.Firstly,based on the density functional theory,in-depth study of manganese-doped nickel-based hybrid electrode is conducted.Then the theoretical calculation results are verified by experiments.Firstly,the crystal models of MnO and NiOOH were preliminarily established,and their structure was optimized.After optimization,the lattice constants obtained with other work were compared and the reliability of the theoretical calculation work was proved.Secondly,based on the above optimized single crystal models of MnO and NiOOH,the Mn-NiOOH@Ni and Mn-NiOOH@C models were established to simulate electrode materials based on nickel and carbon cloth,respectively.And The first-principles calculations were used to calculate their energy band structure and density of electronic states.By analyzing the calculation results,the physical mechanism of the doping modification to improve the energy storage performance of its electrode material was revealed.Furthermore,in order to verify the accuracy of the above theoretical calculations,a manganese-doped nickel-based material was prepared by a hydrothermal method and characterized by SEM,XRD,and EDS.Then the Mn-NiOOH@Ni electrodes were prepared by direct coating.At the same time,the effect of different doping on the energy storage properties of Mn-NiOOH@Ni electrodes was explored using cyclic surface response method.These prove the correctness of the above model calculation results,and determine the best preparation conditions for manganese-doped nickel-based materials.Finally,a flexible electrode based on carbon cloth was fabricated and assembled into a flexible supercapacitor.By comparing the test results with the calculated results,the reliability and accuracy of the calculated results were successfully verified.Theoretical research on capacitive energy storage materials has provided support.