CN103474257A - Preparation method for graphene oxide load cupric oxide lithium ion capacitor electrode materials - Google Patents

Abstract

The invention provides a preparation method for graphene oxide load cupric oxide lithium ion capacitor electrode materials. The preparation method includes the first step of placing 0.5-1g graphite oxide in 50-60ml isopropanol, stirring the mixture evenly and carrying out ultrasonic treatment for three hours to obtain graphene oxide; the second step of mixing 5mmol sodium nitrate, 5-15mmol cupric nitrate and 50-60ml deionized water, carrying out magnetic stirring on the mixture for 30 minutes until the sodium nitrate and the cupric nitrate are full dissolved, slowly dropwise adding stronger ammonia water, and slowly adjusting the PH value to 11+/-0.5; the third step of adding the obtained solution into the graphene oxide, carrying out magnetic stirring for 30 minutes, carrying out ultrasonic treatment for three hours, and then carrying out oil bath circumfluence at 90 DEG C to react continuously for 12 hours; the fourth step of scrubbing repeatedly, transferring the obtained black powder to a culture dish, and enabling the black powder to react in air at 180-250 DEG C for 12 hours to obtain the graphene oxide load cupric oxide lithium ion capacitor electrode materials. According to the preparation method, the raw materials are abundant in reserves, easy to obtain and low in cost; lithium ions are high in capacitive performance, good in big ratio performance and stable in cycle performance.

Description

A kind of preparation method of graphene oxide-loaded cupric oxide lithium-ion capacitor electrode material

Technical field

That the present invention relates to is a kind of preparation method of lithium-ion capacitor electrode material, specifically a kind of preparation method of the electrode material that contains the CuO/GO composite material.

Background technology

Along with the fast development of global economy, the exhausting and more and more serious environmental problem of fossil fuel, for effectively, clean energy resource clean and sustainable development is more and more urgent.In recent years, electrochemical capacitor or ultracapacitor have attracted a large amount of concerns, mainly because their high power density is large, life cycle is long, can make up the little and battery of traditional dielectric capacitor (having high-power output) capacity, fuel cell (the having high-energy stores) shortcoming that power density is low.But meanwhile, the low energy densities of electric chemical super capacitor and high manufacturing cost have stoped its further development.For the low shortcoming of energy density that overcomes electric chemical super capacitor, the most frequently used method is exactly the electrode material of Development of Novel.Nowadays the carbon-based material that the electrode material of main flow is porous the most, although the specific area of carbon-based material is larger, but, in the middle of the process discharged and recharged at it, electric charge only physical store at the interface of loose structure, therefore, its capacitive property has been subject to serious restriction, and people are referred to as double electric layer capacitor to this capacitor.In order to improve the energy density that double electric layer capacitor is lower, electroactive substance can be doped in the middle of the carbon-based electrode material, this capacitor that contains the electroactive substance electrode material is referred to as faraday wild goose capacitor.This capacitor can produce the ratio electric capacity larger than double electric layer capacitor and higher energy density.Under identical electrode area, faraday wild goose capacitor can be 10～100 times of double electric layer capacitor capacity.

The key factor that affects ultracapacitor development have electrode material, with the electrolyte of electrode material coupling and the technology of preparing of electrode etc.Electrolyte commonly used is aqueous electrolyte, but has the shortcoming of decomposition voltage window narrows.Because the decomposition voltage window of organic electrolyte is wide, can make capacitor there is higher operating voltage and specific energy, become the focus of ultracapacitor research from now on.Using the ultracapacitor that lithium-ion electrolyte is organic electrolyte is lithium-ion capacitor.Specifically can be referring to document Zhao H, Pan L, Xing S, et al.Vanadium oxides-reduced graphene oxide composite for lithium-ion batteries and supercapacitors with improved electrochemical performance[J] .Journal of Power Sources, 2013,222:21-31. and CuO/graphene composite as anode materials for lithium-ion batteries[J] .Electrochimica Acta, 2011,56:2306-2311.

Summary of the invention

The purpose of this invention is to provide a kind of cheap, the preparation method of the graphene oxide-loaded cupric oxide lithium-ion capacitor electrode material that energy density is high.

The object of the present invention is achieved like this:

(1), the 0.5-1g graphite oxide is placed in to the isopropyl alcohol of 50-60mL, the rear ultrasonic processing that stirs obtains graphene oxide in 3 hours;

(2), the copper nitrate of the sodium nitrate of 5mmol, 5-15mmol and 50-60mL deionized water are mixed, magnetic agitation 30 minutes until sodium nitrate and copper nitrate dissolve fully;

(3), in step (2) gained solution, slowly drip concentrated ammonia liquor, continuous agitating solution in the process of dropping, slowly regulate pH value to 11 ± 0.5;

(4), step (3) gained solution is added in step (1) gained graphene oxide, magnetic agitation 30 minutes, ultrasonic processing subsequently 3 hours, then carry out 90 ℃ of oil baths and reflux, sustained response 12 hours;

(5), mixed solution is carried out to suction filtration, use the deionized water cyclic washing;

(6), the black powder that obtains after washing is transferred in culture dish, add upper cover, then in air 180-250 ℃ react 12 hours, obtain graphene oxide-loaded cupric oxide electrode material.

The present invention be take CuO/GO as work electrode, to the lithium sheet, is to electrode, take polypropylene as barrier film, lithium hexafluoro phosphate LiPF ₆for electrolyte, assembling CuO/GO electrode system is discharged and recharged in the 0-3.0V voltage range, can obtain the lithium-ion capacitance capacity.

Essence of the present invention is the electrode structure that adopts lithium ion battery, and the CuO/GO of usining replacement charcoal etc., as electrode material, are discharged and recharged in lithium-ion electrolyte, form the electrode of lithium-ion capacitor, obtain the lithium-ion capacitance capacity.

The invention has the advantages that graphene oxide (GO) is a kind of important derivatives of Graphene, it is characterized in that on two dimensional surface and edge having a large amount of oxygen-containing functional groups, it has high specific area and high ionic diffusion coefficient the structures shape of this uniqueness.GO and Graphene are contrasted, and have saved reduction step subsequently, have simplified the operation of experiment, reduced the pollution of environment, and raw material are very abundant, and preparation technology is simple, and than carbon nano-tube, its price is more cheap.CuO belongs to transition metal oxide, has low price, and toxicity is little, environmental friendliness, the advantage such as specific capacity is large, the shortcoming such as still, cupric oxide belongs to semiconductor, and poorly conductive is arranged, and bulk effect is obvious.Upper by nano level CuO being loaded on equably to GO, utilize the high-specific surface area of GO and the performance that higher conductivity improves the CuO/GO composite material.Nano level CuO is evengranular to be distributed on graphene oxide, not only can prevent the reunion of GO, but also certain capacity can be provided.Utilize the electrode material of CuO/GO composite material as ultracapacitor, not only the raw material reserves are rich and easy to get, cheap, and the lithium-ion capacitance performance is high, large good rate capability, stable cycle performance.

Embodiment

For effect of the present invention is described better, below with instantiation, be illustrated.

(1), take the beaker that the 1g graphite oxide is put into 100mL, add the isopropyl alcohol of 60mL, stir, follow ultrasonic processing 3 hours, until the graphite oxide in solution is dispersed in isopropyl alcohol.Long-term placement can not produce precipitation yet, and at this time graphite oxide has been peeled off into graphene oxide by ultrasonic, is abbreviated as GO; (2), take the sodium nitrate of 5mmol, the copper nitrate of 5-15mmol and 60mL deionized water are put in the beaker of 100mL simultaneously, magnetic agitation 30 minutes until sodium nitrate and copper nitrate dissolve fully; (3), in above-mentioned solution, slowly drip concentrated ammonia liquor, continuous agitating solution in the process dripped, slowly regulate the pH value to being approximately 11 left and right, can observe solution in dripping the concentrated ammonia liquor process in, at first there is a large amount of white precipitates to generate, increase along with ammonia vol, precipitation fades away, and last solution becomes blue settled solution; (4), (3) solution is poured in (1), magnetic agitation 30 minutes, ultrasonic processing subsequently 3 hours, then transfer in round-bottomed flask, carries out 90 ℃ of oil baths and reflux, sustained response 12 hours; (5), above-mentioned mixed solution is carried out to suction filtration, use deionized water cyclic washing 5 times; (6), the black powder that obtains after washing is transferred in culture dish, add upper cover.Then in air 180-250 ℃ the reaction 12 hours, obtain graphene oxide-loaded cupric oxide CuO/GO electrode material.

Application example 1

The CuO/GO of 10mmol copper nitrate load of take is active material, acetylene black is conductive agent, polyvinylidene fluoride (PVDF) is binding agent, be conductive agent in mass ratio: binding agent: active material=10:10:80 carries out proportioning, make the CuO/GO electrode, take the CuO/GO electrode as work electrode, and pour lithium slice is to electrode.The polypropylene diaphragm that barrier film is diameter 18mm, electrolyte is 1molL ^-1liPF ₆/ EC:DEC:EMC=1:1:1.Assembling CuO/GO electrode system is discharged and recharged, at 1Ag in 0～3.0V voltage range ^-1under current density, the rear specific discharge capacity of circulation 100 circle can maintain 320Fg ^-1.

Application example 2

The CuO/GO of 5mmol copper nitrate load of take is active material, acetylene black is conductive agent, polyvinylidene fluoride (PVDF) is binding agent, be conductive agent in mass ratio: binding agent: active material=10:10:80 carries out proportioning, make the CuO/GO electrode, take the CuO/GO electrode as work electrode, and pour lithium slice is to electrode.The polypropylene diaphragm that barrier film is diameter 18mm, electrolyte is 1molL ^-1liPF ₆/ EC:DEC:EMC=1:1:1.Assembling CuO/GO electrode system is discharged and recharged, at 1Ag in 0～3.0V voltage range ^-1under current density, the rear specific discharge capacity of circulation 100 circle can maintain 250Fg ^-1.

Application example 3

The CuO/GO of 15mmol copper nitrate load of take is active material, acetylene black is conductive agent, polyvinylidene fluoride (PVDF) is binding agent, be conductive agent in mass ratio: binding agent: active material=10:10:80 carries out proportioning, make the CuO/GO electrode, take the CuO/GO electrode as work electrode, and pour lithium slice is to electrode.The polypropylene diaphragm that barrier film is diameter 18mm, electrolyte is 1molL ^-1liPF ₆/ EC:DEC:EMC=1:1:1.Assembling CuO/GO electrode system is discharged and recharged, at 1Ag in 0～3.0V voltage range ^-1under current density, the rear specific discharge capacity of circulation 100 circle can maintain 280Fg ^-1.

Claims (1)

1. the preparation method of a graphene oxide-loaded cupric oxide lithium-ion capacitor electrode material is characterized in that:

(1), the 0.5-1g graphite oxide is placed in to the isopropyl alcohol of 50-60mL, the rear ultrasonic processing that stirs obtains graphene oxide in 3 hours;

(2), the copper nitrate of the sodium nitrate of 5mmol, 5-15mmol and 50-60mL deionized water are mixed, magnetic agitation 30 minutes until sodium nitrate and copper nitrate dissolve fully;

(3), in step (2) gained solution, slowly drip concentrated ammonia liquor, continuous agitating solution in the process of dropping, slowly regulate pH value to 11 ± 0.5;

(4), step (3) gained solution is joined in step (1) gained graphene oxide, magnetic agitation 30 minutes, ultrasonic processing subsequently 3 hours, then carry out 90 ℃ of oil baths and reflux, sustained response 12 hours;

(5), mixed solution is carried out to suction filtration, use the deionized water cyclic washing;

(6), the black powder that obtains after washing is transferred in culture dish, add upper cover, then in air 180-250 ℃ react 12 hours, obtain graphene oxide-loaded cupric oxide electrode material.