Université Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS , 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France.
ACS Appl Mater Interfaces. 2015 Oct 7;7(39):21673-81. doi: 10.1021/acsami.5b06699. Epub 2015 Sep 24.
Poly(ethylenedioxythiophene) (PEDOT) films were electrodeposited galvanostatically from an EDOT/sodium dodecyl sulfate solution in water, through a carboxylated polystyrene template monolayer self-assembled on ITO, after which the template was dissolved away in tetrahydrofuran. Analysis of the films by scanning electron microscopy and atomic force microscopy reveals large-area PEDOT honeycomb structures. The morphology of these structures was varied electrochemically, as the effective thickness and, surprisingly, the shape of the honeycomb arrangement depend on the polymerization time. Using nanospheres of 1 μm diameter and charge densities between 12 and 30 mC cm(-2) for electrodeposition generates PEDOT hexagons with very thin rectilinear walls 30-35 nm-thick and 800 nm-long, whereas at higher charge densities, circular bowls are created with 60 nm walls separating adjacent bowls; triangular areas as small as 0.02 μm(2) develop at the intersection of three nanospheres. These morphologies are specific to the use of carboxylated PS spheres and a water-based solution with a surfactant in the galvanostatic electrodeposition mode. Using smaller nanospheres, i.e. 500 nm in diameter, makes it possible to reach PEDOT hexagons with rectilinear walls as small as 11-17 nm-thick and 300 nm-long; circular bowls with 25-35 nm walls separating adjacent bowls and triangular areas as small as 0.003 μm(2) can also be generated. The wettabilities of the surfaces depend markedly on the pore depth of the PEDOT nanostructure, with contact angles going from 82° to 130° with increasing pore size. Finally these nanostructured PEDOT electrodes were used in Grätzel-type dye-sensitized solar cells (DSSCs) as Pt-free counter-electrodes, with an increase in the yield from 7.0 (bulk PEDOT) to 8.1%.
聚（3,4-亚乙基二氧噻吩）（PEDOT）薄膜通过在 ITO 上自组装的羧化聚苯乙烯模板单层的恒电流电化学聚合 EDOT/十二烷基硫酸钠在水中进行电沉积，然后将模板在四氢呋喃中溶解。通过扫描电子显微镜和原子力显微镜分析薄膜，揭示了大面积 PEDOT 蜂窝状结构。这些结构的形态可以通过电化学方法进行改变，因为有效厚度，而且令人惊讶的是，蜂窝状排列的形状取决于聚合时间。使用直径为 1 μm 且电荷密度在 12 至 30 mC cm(-2) 之间的纳米球进行电沉积，生成具有非常薄的直线壁（厚度为 30-35 nm）且长度为 800 nm 的 PEDOT 六边形，而在较高的电荷密度下，会生成具有 60 nm 厚的壁分隔相邻碗的圆形碗；在三个纳米球的交点处会形成面积小至 0.02 μm(2) 的三角形区域。这些形态是使用羧化 PS 球和在恒电流电沉积模式下使用含有表面活性剂的水基溶液的特定形态。使用直径更小的纳米球，例如 500 nm，使得可以达到具有厚度仅为 11-17 nm 且长度为 300 nm 的直线壁的 PEDOT 六边形；可以生成具有 25-35 nm 厚的壁分隔相邻碗和面积小至 0.003 μm(2) 的三角形区域的圆形碗。表面的润湿性明显取决于 PEDOT 纳米结构的孔深，随着孔径的增大，接触角从 82°增加到 130°。最后，这些纳米结构化的 PEDOT 电极被用作 Grätzel 型染料敏化太阳能电池（DSSC）中的无 Pt 对电极，产率从 7.0（块状 PEDOT）增加到 8.1%。
