Nickel cobalt base-carbon nanotube composite electrode material and preparation method thereof

Abstract

The invention discloses a nickel-cobalt bimetallic hydroxide / carbon nanotube novel composite electrode material for super capacitors and a preparation method thereof. The method comprises finishing the surface of a carbon nanotube to form an aqueous solution with good dispersity; adding nickel salt, cobalt salt and an additive, and then adding an appropriate quantity of an alkali source, performing suction filtration, washing, and drying after reaction in an oil bath with a mild condition so as to obtain highly uniformly dispersed nickel-cobalt bimetallic hydroxide / carbon nanotube novel composite. The nickel-cobalt bimetallic hydroxide / carbon nanotube novel composite is used as the electrode material of the super capacitor so that both the double-layer capacitance of the carbon nanotube and the pseudocapacitance of the hydroxide can be used and the carbon nanotube has good electrical conductivity, dispersion promoting performance and mechanical strength. The optimized and synthesized novel composite electrode material has a specific capacitance value of 1558F / g when having a current density of 1A / g. When the current density is increased to 10A / g, the specific capacitance value is still maintained at 1358F / g, thereby achieving a retention rate of 87. 2% so that the novel composite electrode material has good magnification and good charge and discharge cycle stability. The method for synthesizing the material is simple, mild in condition, and cheap in raw material and is a good preparation method. The electrode material has excellent performance.

Description

technical field [0001] The invention relates to the field of preparation of novel electrode materials for supercapacitors, in particular to a novel nickel-cobalt double metal hydroxide / carbon nanotube composite electrode material and a preparation method thereof. Background technique [0002] In recent years, with the development of the global economy, the shortage of resources and energy has become increasingly serious, and the environmental pollution has become more serious. The search for clean and renewable new energy has become a major problem to be solved urgently for mankind. As an energy storage device, supercapacitor has the advantages of fast charging and discharging, long cycle life, green and pollution-free, etc. It has great application value in mobile communications, aerospace, electronic products, electric vehicles and other fields, and has received widespread attention. . Electrode materials are the core part of supercapacitors, and the development of electr...

AI Technical Summary

Problems solved by technology

However, during the recycling process of nickel-cobalt double metal hydroxide electrode materials, different degrees of phase transitions will occur, and the volume change between different phases will damage the structure, resulting in the gap between the active materials and between the active materials and the current collector. The contact resistance between them increases, so the utilization rate of the active material decreases sharply, and the electrochemical activity decreases.

[0005] Chinese patent (CN105161313A) utilizes hydrothermal method to prepare a kind of nickel cobaltate / carbon nanotube composite electrode material, and its specific capacity reaches about 900F / g, and stable type is good simultaneously, but reaction condition requirement is higher; Chinese patent (CN103560018A) A carbon nanotube and nickel oxide composite electrode material prepared by an impregnation method is provided. The material has good stability (500 cycle specific capacitance retention rate of 85%), but the specific capacitance needs to be improved (155F / g); Chinese patent (CN106058218A) discloses a carbon nanotube and nickel-cobalt-aluminum-magnesium quaternary composite positive electrode material prepared by a pyrolysis catalytic method, but the composition of the material is complex and the preparation method is harsh (calcination temperature reaches 600-1000° C.)

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