石墨烯及石墨烯基复合柔性透明电极的研制

Synthesis of Graphene and Graphene-Based Flexible Transparent Electrode

采用改进的化学气相沉积法制备了缺陷较少的石墨烯,并以旋涂导电聚合物薄膜为石墨烯中间基底,进行石墨烯薄膜的转移和柔性透明复合电极的制备。采用激光拉曼光谱、光学显微镜、动静态接触角仪、原子力显微镜、四探针测试仪和透光率仪等对制备的材料进行表征。分析了甲烷通入方式和石墨烯转移对石墨烯质量的影响,以及表面活性剂、旋涂转速对电极表面形貌及光学与电学性能的影响。结果表明:本实验环境下,使用的甲烷流量范围能制备出单层或少层的石墨烯,而先低后高式梯度浓度通入甲烷有利于减少石墨烯的缺陷,其ID/IG值最小,为0.034。双离子型表面活性剂改善了导电聚合物在石墨烯表面成膜的形貌,其表面粗糙度在8 nm左右,且表面活性剂浓度为10 mmol/L时,其在石墨烯表面的静态接触角为37.17°。选取最佳成膜导电聚合物水溶液配比,并在500 r/min旋涂转速下,所得复合电极的方阻为274.8Ω/sq,相比石墨烯降低了39.77%;当复合旋涂转速大于1 500 r/min时,复合电极透过率大于90%。

A hybrid flexible transparent electrode including graphene and PEDOT：PSS film was obtained. The graphene with few defects was prepared by modified chemical vapor deposition, and the PEDOT：PSS film was spin-coated upon the graphene to support it as a substrate. After the transfer process, the Raman spectra, optical microscope, dynamicstatic contact angle meter, Atomic force microscope and four-probe transport measurements were performed to characterize the properties of the hybrid. The influence of the methane introduction, the transfer process of graphene, the amount of surfactant and the spin speed on the properties of the hybrid were analyzed. The results showed that with the flux condition,single or few layer graphene could be produced. The method by using gradient methane concentration could decrease the defect of graphene and the minimum value of ID/IG was 0.034. Surfactant could improve the morphology of hybrid electrode and the roughness of hybrid electrode was about 8 nm. With a 10 mmol/L surfactant being used, the static contact angle was37.17°. As to the resistance of the prepared graphene, the hybrid sheet resistance was 274.8Ω/sq, with 39.77% reduction after 500 r/min PEDOT：PSS spin-coated. With the spin-coated speed of the PEDOT：PSS film higher than 1 500 r/min, the transmittance of the hybrid electrode could be greater than 90%.