以氧化铜箔为衬底,并在氮气条件下加热退火来钝化铜箔表面的有利形核位,利用低压化学气相沉积法制备大晶畴、高质量的石墨烯薄膜,随后采用转移/叠加技术制备出了不同层数的石墨烯透明导电薄膜,研究层数对其光电学性能的影响。结果表明,石墨烯晶畴的尺寸达到了650μm,平均生长速率高达43.3μm/min;在550nm处,单层石墨烯透明导电薄膜的透光率为94.3%,方阻为678Ω/□;随着层数的增加,石墨烯透明导电薄膜的透光率和方阻均线性递减,当层数增大到5时,其透光率降低至80.1%,方阻则降至约287Ω/□;这种变化规律与石墨烯特殊的价键结构有关。
mono-layer graphene(rGO) with large rGO domains were fabricated by low pressure chemical vapor deposition method on oxidized copper foil,which was heated and annealed in nitrogen atmosphere to passivate the preferential active sites for rGO nucleation.And then the fabricated films were transferred onto transparent quartz glass to prepare 1～5 layer rGO transparent conductive electrode (TCE) films.The effects of the layer number of rGO on the optoelectronic properties of the TCE films was studied.The results indicated that the grain size of fabricated rGO domains was up to 650μm with the average growth rate of 43.3μm/min.With the number of layers increase,the transmittance and the sheet resistance of the TCE films deceased linearly.The transmittance of the mono-layer rGO film was about 94.3% at the wave length of 550 nm and the sheet resistance was 678Ω/□.While when the layer number increased to 5,the transmittance of 5-layer rGO film at 550 nm was decreased to 80.1% and the sheet resistance decreased to 287Ω/□.This kind of variation of the transmittance and the sheet resistance of the TCE films versus the layer number could be attributed to the special valence bond structure of rGO.
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基金资助
陕西省自然科学基础研究计划(青年人才项目)(2017JQ5107);陕西省教育厅自然科学专项(17JK0571);攀枝花市科技项目(2017CYG18)
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