Study On The Preparation And Performance Of Thin-Film Electrode Materials For Electrochemical Supercapacitor

Supercapacitor is a new energy storage device.Because of its rapid charge-discharge energy storage,high power density,maintenance free,long cycle life and friendly to the environment,supercapacitor has focus scientists interest all the world.It is the most important factors which get higher performance of super-capacitors to improve the specific capacitance and the practicality of Electrode materials.In this thesis, CNTs/GP, MnO₂-CNTs/GP and PANI-CNTs/GP thin film electrode materials in the soft graphite paper were prepared by electrophoretic deposition and electrodeposition methods. XRD,FTIR,FE-SEM were used to characterize the materials. Electrochemical performance of the materials were analyzed by cyclic voltammetry,galvanostatic charge-discharge.XRD and FE-SEM revealed that:, in the mixed solution of 5 mmol/L MnSO₄+50 mmol/L KCl, MnO₂ depositions which includedα-MnO₂,γ-MnO₂ and hydrous manganese oxide crystal mixture powder materials were obtained by electrodeposition methods in the potential of 1 V. The shape of MnO₂ depositions is five sub-spherical particles grabbing, about 100 nm in size.PANI-CNTs/GP is prepared by electrodeposition methods in the mixed solution of 0.05 mol/L aniline+ 0.5 mol/L H₂SO₄ with the potential of 1 V. PANI deposition profile along the growth of CNTs, with the longer deposition time, deposition on the PANI increases. Electrochemical performance of PANI-CNTs/GP composite thin-film electrode materials is best when the deposition time is up to 20 min.Electrochemical performance of the materials were analyzed by CV curves test and constant current charge-discharge test.In the 0.5 mol/L Na₂SO₄ solution with scan rate of 0.005 V/s, Specific capacitance of CNTs/GP material is 7.8 F/g, MnO₂-CNTs/GP material is 420 F/g. Specific capacitance of PANI-CNTs/GP material is 485.4 F/g with 0.01 V/s in the solution of 1 mol/L H₂SO₄.