A kind of method controlling the Enhancing Nucleation Density of its epontic Graphene
Technical field
The present invention relates to a kind of method controlling the Enhancing Nucleation Density of its epontic Graphene, belong to field of material technology.
Background technology
Graphene has excellent electricity, mechanics, optics, thermal property, has broad prospects in fields such as electricity device, photoelectric device, radiating elements, and the preparation of the large size of Graphene, high quality is the prerequisite of its widespread use.
Chemical vapour deposition (CVD) method is the means being expected to realize graphene film suitability for industrialized production most, its reaction principle is: copper catalysis makes carbon-source gas decompose, carbon atom forms several nucleating centers at copper foil surface, and final grain growth links film forming.The quality of Graphene depends on its monocrystalline size, namely Enhancing Nucleation Density to a great extent.Researcher attempts the graphene film that the growth of various approach has large single crystal size always.While the guarantee speed of growth, improve the monocrystalline size of Graphene, namely reduce its Enhancing Nucleation Density, the quality of raising Graphene, the application of promotion Graphene are had great importance.
Current control Graphene the method for copper foil surface Enhancing Nucleation Density comprise control the air rate of methane, hydrogen, gas pressure intensity, the roughness of copper foil surface, growth temperature and high temperature under pass into dioxygen oxidation and reduce the methods such as copper foil surface activity site.This method of dioxygen oxidation reduction copper foil surface activity site is passed into very harsh for requirement for experiment condition, unfavorable suitability for industrialized production under method set forth above, particularly high temperature.
Summary of the invention
technical problem:in order to control the method for the Enhancing Nucleation Density of its surface growth Graphene, to solve the problems such as existing method complex process, the speed of growth be low, the invention provides a kind of method controlling the Enhancing Nucleation Density of its epontic Graphene.
technical scheme:the method of the Enhancing Nucleation Density of its epontic Graphene of control of the present invention, comprises the steps:
1) preparing mass concentration is the hydrogen peroxide of 5-30%;
2) soaked wherein by Copper Foil, Copper Foil is by hydrogen peroxide oxidation;
3) then CVD growing graphene is used for this pretreated Copper Foil.
Described step 2) in soak time be 5-60s.
Preferably,
Hydrogen peroxide mass concentration in described step 1) is 5%.
Described step 2) in soak time be 30s.
The CVD growing graphene method of described step 3) is as follows: by Copper Foil pretreated for hydrogen peroxide with do not carry out pretreated Copper Foil and be placed in parallel in growth furnace, control methane, hydrogen flow and be respectively 20 and 100sccm, mixing pressure is 200pa, growth temperature 1045 DEG C, growth time 1 minute.
The square ratio juris of the Enhancing Nucleation Density of its epontic Graphene of control of the present invention is as follows: the impurity activity of copper foil surface is comparatively strong, is the easy nucleation site of Graphene.Hydrogen peroxide pre-treatment makes copper foil surface be oxidized, at high temperature the oxygen of copper foil surface and surface impurity generation chemical reaction, thus reduces the density in copper foil surface active centre, reduces the Enhancing Nucleation Density of Graphene.
beneficial effect:be compared to the method that other control copper foil surface Graphene Enhancing Nucleation Density, present method is simple and easy to do, only needs to carry out to Copper Foil the Enhancing Nucleation Density that hydrogen peroxide dipping just effectively can reduce copper foil surface Graphene in advance.Meanwhile, present method also can with other control method conbined usage, on the basis of present method, by controlling air rate, gas pressure intensity, copper foil surface roughness, growth temperature etc., Enhancing Nucleation Density can be reduced further, improving the monocrystalline size of graphene film.
Accompanying drawing explanation
Fig. 1 is the 500 times of optical microscope picture (light tone region is single-layer graphene) distributed without the single-layer graphene forming core of the pretreated copper foil surface of hydrogen peroxide.
Fig. 2 is the 500 times of optical microscope picture (light tone region is single-layer graphene) distributed through the single-layer graphene forming core of the 5% hydrogen peroxide pre-treatment copper foil surface of 30 seconds.
Specific embodiment
Embodiment 1
The method of the Enhancing Nucleation Density of its epontic Graphene of control of the present invention, comprises the steps:
1) compound concentration mass concentration is 5% hydrogen peroxide solution;
2) obtain the Copper Foil that a slice thickness is 25 microns, and process 30 seconds in the hydrogen peroxide of 5%;
3) CVD growing graphene: by Copper Foil pretreated for hydrogen peroxide with do not carry out pretreated Copper Foil and be placed in parallel in growth furnace, control methane, hydrogen flow and be respectively 20 and 100sccm, mixing pressure is 200pa, growth temperature 1045 DEG C, growth time 1 minute;
By the Copper Foil hydrogen peroxide process number minute after growth, re-use the Enhancing Nucleation Density of observation by light microscope Graphene at copper foil surface.Fig. 1 is the 500 times of optical microscope picture (light tone region is Graphene) distributed without the single-layer graphene forming core of the pretreated copper foil surface of hydrogen peroxide.Fig. 2 is the 500 times of optical microscope picture (light tone region is Graphene) distributed through the single-layer graphene forming core of the 5% hydrogen peroxide pre-treatment copper foil surface of 30 seconds.Can find out, in advance the Enhancing Nucleation Density that hydrogen peroxide dipping just effectively can reduce copper foil surface Graphene be carried out to Copper Foil.