Yu Shiyou, Li Ning, Higgins Drew, Li Deyu, Li Qing, Xu Hui, Spendelow Jacob S, Wu Gang
School of Chemical Engineering & Technology, Harbin Institute of Technology , Harbin, 150001, China.
ACS Appl Mater Interfaces. 2014 Nov 26;6(22):19783-90. doi: 10.1021/am504941p. Epub 2014 Nov 5.
Substrate supported conductive thin films are prepared by the self-assembly of graphene oxide (GO) on a cationic polyacrylamide (CPAM) layer followed by a subsequent chemical reduction. During self-assembly, the dispersed GO nanosheets with a negative zeta potential from solution are spontaneously assembled onto the positively charged CPAM adsorption layer. In addition, CPAM adsorption on the substrate is studied with an electrochemical quartz crystal microbalance (EQCM), showing adsorption stabilization could be established in less than 150 s. The electrostatic interactions between GO and CPAM are investigated by changing the polarization potential with EQCM for the first time, and optimal conditions for facilitating self-assembly are determined. The self-assembled GO/CPAM films are further characterized by Raman spectroscopy, infrared spectroscopy and atomic force microscopy. Importantly, reduced GO (R-GO)/CPAM composite films exhibiting a sheet resistance of 3.1 kΩ/sq can be obtained via in situ reduction in sodium borohydride for 20 min at room temperature. This provides a simple, highly effective, and green route to prepare conductive graphene-based composite thin films.
通过在阳离子聚丙烯酰胺（CPAM）层上自组装氧化石墨烯（GO），随后进行化学还原，制备了基底支撑的导电薄膜。在自组装过程中，溶液中具有负ζ电位的分散氧化石墨烯纳米片自发地组装到带正电荷的CPAM吸附层上。此外，用电化学石英晶体微天平（EQCM）研究了CPAM在基底上的吸附，结果表明在不到150秒的时间内即可建立吸附稳定性。首次通过EQCM改变极化电位研究了GO与CPAM之间的静电相互作用，并确定了促进自组装的最佳条件。通过拉曼光谱、红外光谱和原子力显微镜对自组装的GO/CPAM薄膜进行了进一步表征。重要的是，在室温下用硼氢化钠原位还原20分钟，可以得到表面电阻为3.1 kΩ/sq的还原氧化石墨烯（R-GO）/CPAM复合薄膜。这为制备导电石墨烯基复合薄膜提供了一条简单、高效且绿色的途径。
