Proposal for the Undergraduate Research Award Title of the Activity ...

Proposal for the Undergraduate Research AwardTitle of the Activity:Controlled Growth of Graphene by Chemical Vapor DepositionSPS Chapter of Southeast University (China)Zone 18, 6540This proposal for the Undergraduate Research Award is preparedby:Tian-Chen JinYu-Lu LiuJi-Long LiuQi LiuFaculty Advisor:Zhi-Yong ZhouProgram Advisor:Zhen-Hua NiAmount requested for this activity: $1,900.00Date of Submission: November 14, 2011

AbstractGraphene, firstly isolated in 2004, is a new type of carbon materials, whichcontains a single- or few-layered sheet of Sp2-bonded carbon atoms. This specialatomic structure gives graphene rich physical properties and wide potentialapplications. It has excellent electrical, mechanical, thermal and optical properties andhas wide applications in nanoeletronic devices, transparent conductive films, powerstorage, composites materials et al. In our program, CVD method will be used tofabricate large area and high quality graphene, which will pave the way for itsapplications. We will also investigate the growth mechanism of graphene on differentmetal substrates.

Background:Graphene is a kind of magical materials which combines special 2D structure and diverseoutstanding performance. The electron mobility of graphene is about 100 times faster than silicon,exhibiting the ballistic transport properties in submicron-scale at room temperature. Graphene isalmost transparent with only 2.3% photoabsorption in a wide excitation range. Besides, grapheneis about 100 times as strong as steel, excellent flexibility and ductility, up to 2600m2/g specificsurface area. Its thermal conductivity is 10 times faster than copper. With these excellent physicalproperties, graphene has wide application in many fields. For instance, with its super-high electronmobility it can be used as high frequency transistor; with its high conductivity, high transmissionand flexibility, it can be used as flexible transparent conductive films which is frequently used intouch screen and solar cell, etc; with its high strength and high thermal conductivity, it canimprove the performance of traditional materials; and with its high specific surface area, it can beused as electrode materials for high performance lithium battery and super capacitor.The preparation of graphene is the premise and basis of understanding its physics andrealizing its application. Mechanical cleavage of graphite is the earliest way to prepare graphenewith high quality and excellent electrical properties, which has been widely used in studyinggraphene's physical properties and apparatus. However, this method is inefficient, with bigrandomicity and low productivity, which is difficult to realize large-scale production. Hereafter,the epitaxial growth based on SiC single crystal and metal single crystal, chemical exfoliation,chemical vapor deposition (CVD) and organic synthesis have been developed. Epitaxial growthbased on SiC can obtain relative high quality graphene, but the preparation condition isdemanding, and it need high level vacuum, meanwhile, the cost is high and the productivity is low.

Chemical exfoliation can be used for large-scale preparation, however it has numerous defects.Recently, CVD is a kind of new way to prepare graphene, the process is simple and the quality ishigh, which can also be used in large-scale production, meanwhile, it can be easily transferred toother substrate. Therefore, CVD graphene is widely used in making nano-electronic devices andtransparent conducive films, and it gradually becomes the primary ways to prepare high qualitygrapheme films.Recently, researchers focused on large area preparation of graphene by CVD. Nickel andCopper substrates are most widely used. The grain size of Nickel is small and the number ofgraphene layers achieved was difficult to be controlled. Copper substrates were used to preparedsingle-layered graphene. Recently, 30 inches of graphene films was prepared on Copper substrateand the quality and conductivity were improved correspondingly. However, how to furtherimprove the quality, i.e. single crystal domain size, and the controllability of graphene thickness isstill a tough issue and research interest, which restricts the application of graphene.Research plan:In this program, we will investigate the growth mechanism of graphene on different metalsubstrates and the effect of growth condition on graphene structure by CVD method. We willprepare large area, high quality graphene with good controllability, which will pave the way forapplications.First, we will search the references on CVD graphene and be familiar with the CVD growthmethod. We will then build CVD furnace and prepare graphene on different substrates(Cu, Ni, andtheir allys). We will use substrate corrosion method to remove the metal substrate and transfergraphene to SiO2/Si substrates. Optical microscope will be used to observe the uniformity. Raman

BudgetMaterials (carbon source, gas, etc.) $1,000.00Substrates (copper, nickel, etc.) $500.00Chemicals $200.00Furnace Tubes $200.00Total budget and funds requested $1,900.00