Layer-by-layer assembly of ultrathin composite films from micron-sized graphite oxide sheets and polycations
Layer-by-layer assembly of ultrathin composite films from micron-sized graphite oxide sheets and polycations
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DOI：
10.1021/cm981085u
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发表时间：
1999-03-01
影响因子：
8.6
通讯作者：
Gorchinskiy, AD
中科院分区：
文献类型：
--
作者：
Kovtyukhova, NI;Ollivier, PJ;Gorchinskiy, AD
以天然石墨为原料制备了氧化石墨单层胶体，并通过静电自组装在阳离子表面生长成单层和多层薄膜。采用阴离子氧化石墨烯片和阳离子聚烯丙胺盐酸盐（PAH）交替吸附法制备了多层膜。单层膜由11-14埃厚的氧化石墨烯薄片组成，横向尺寸在150 nm到9 μ m之间。用胺单层膜引发的硅衬底形成了部分氧化石墨烯单层膜，但用Al13O4-(OH)(24)(H2O)(12)（7+）离子引发的表面形成了密集的平铺膜，覆盖了大约90%的表面。当使用碱性氧化石墨烯胶体时，单层组装工艺从悬浮液中选择最大的薄片（从900 nm到9 μ m）。在这种情况下，许多柔性薄片在AFM图像中出现折叠。多层（氧化石墨烯/多环芳烃）(n)薄膜总是比单片和聚合物单层的厚度预期的要厚，这种行为也归因于薄片的折叠。在氧化铟锡和铂电极之间生长的多层（氧化石墨烯/多环芳烃）和（氧化石墨烯/聚苯胺）薄膜表现出二delike行为，并且在导电聚苯胺薄膜上观察到更高的电流。正如预期的那样，由于氧化石墨烯部分还原为碳，这些薄膜的电阻率降低了。
Unilamellar colloids of graphite oxide (GO) were prepared from natural graphite and were grown as monolayer and multilayer thin films on cationic surfaces by electrostatic self-assembly. The multilayer films were grown by alternate adsorption of anionic GO sheets and cationic poly(allylamine hydrochloride) (PAH). The monolayer films consisted of 11-14 Angstrom thick GO sheets, with lateral dimensions between 150 nm and 9 mu m. Silicon substrates primed with amine monolayers gave partial GO monolayers, but surfaces primed with Al13O4-(OH)(24)(H2O)(12)(7+) ions gave densely tiled films that covered approximately 90% of the surface. When alkaline GO colloids were used, the monolayer assembly process selected the largest sheets (from 900 nm to 9 mu m) from the suspension. In this case, many of the flexible sheets appeared folded in AFM images. Multilayer (GO/PAH)(n) films were invariably thicker than expected from the individual thicknesses of the sheets and the polymer monolayers, and this behavior is also attributed to folding of the sheets. Multilayer (GO/PAH), and (GO/polyaniline)(n) films grown between indium-tin oxide and Pt electrodes show diodelike behavior, and higher currents are observed with the conductive polyaniline-containing films. The resisitivity of these films is decreased, as expected, by partial reduction of GO to carbon.