LI Qi , LI Chengmei , LIU Yanjiao , HE Wenxiu
(Chemistry and Chemical Engineering School , Inner Mongolia University of Science and Technology , Baotou 014010 , China)
Abstract : Layered bimetallic hydroxide is an excellent electrode material for supercapacitors . La-doping can theoretically optimize the properties of such materials . However , its specific effects have not yet been revealed. Therefore , La3 + doped nickel-cobalt bimetallic hydroxide (La-NiCo LDH) was prepared by hydrothermal method. On this basis , the effects of La3 + doping amount on the microstruc- ture and electrochemical properties of La-Nico LDH were studied by XRD , XPS , SEM and electrochemical tests . The introduction of La3 + transforms the morphology of the sample from honeycomb microspheres to petal microspheres , and the specific capacitance of the material is greatly improved. At the current density of 1 A/g , the specific capacitance of the Ni-Co LDH material is 812 F/g. After do- ping with La3 + , the specific capacitance of the Ni-Co LDH material is 812 F/g. The specific capacitance of the sample increases to 1 458 F/g. Meanwhile , the electrical conductivity of the material is also improved.
Key words : nickel-cobalt bimetallic hydroxide; La3 + ; supercapacitor; element doping; electrochemical performance