Preparation And Investigation Of Releasable Nial LDH And Its Electrochemical Properties With Nitrogen-doped Graphene Composites

In this paper,the preparation process of graphene materials,nickel-aluminum double hydroxide materials and their self-assembled composites were studied in detail,and the practical application of electrode materials in supercapacitors was discussed as well as.The specific work is as follows:Hydroxylamine-O-sulfonic acid used as a dopant and reducing agent,the reduction of graphite oxide was also completed while modified graphene surface.It had been found that nitrogen-doped graphene revealed better dispersion properties and it was easy to prepare graphene-based composite materials in the subsequent synthesis process.Nickel-aluminum layered double hydroxide with nitrate ion intercalation was synthesized by a simple liquid phase synthesis.This paper had experimentally studied the effects of variable(molar ratio of Ni²⁺,Al³⁺)and variable?total concentration of ions in solution?on the morphology control of NiAl LDH-NO₃ nanomaterials,and further studied the electrochemical properties.The capacitance of NiAl LDH-NO₃ reaches 1600 F g^-1 at a current density of 1 A g^-1 and its specific capacity can still be maintained at 81.25%(1300F g^-1)of the initial capacity when the current density is 10 A g^-1;the cycle stability reached84.6%at a current density of 5 A g^-1 circulating 2000 cycles.The layered NiAl LDH/NNDG composite was prepared by a simple self-assembly process.In this paper,the influence of mass ratio between NiAl LDH and NNDG on the morphology and structure of composites was studied systematically in order to discusse the electrochemical behavior of composites.The results showed that the quality of nickel-aluminum layered double hydroxide/nitrogen-doped graphene was 15,the composite material possessed the best electrochemical performance.The electrochemical performance of NNDG/NiAl LDH-15 exhibits relatively high specific capacitance value of 2100 F g^-1 at a current density of 1 A g^-1,its specific capacity can still be maintained at1650 F g^-1 when the current density is 10 A g^-1;⁸7%retention upon 2000charge/discharge cycles at 5 A g^-1.NNDG/NiAl LDH-15//AC asymmetric supercapacitor device possesses excellent electrochemical performance.The device has a specific capacitance of 166 F g^-1 at a current density of 1 A g^-1,and the asymmetric supercapacitor shows the excellent cycling stability?96%retention within 8000 cycles?at a current density of 5 A g^-1.NNDG/NiAl LDH-15//AC also shows the highest density of 60 Wh kg^-1at power density of 1100 W kg^-1.