Strubbe Filip, Prasad Manoj, Beunis Filip
Electronics and Information Systems and Center for Nano and Biophotonics (NB-Photonics), Ghent University , Sint-Pietersnieuwstraat 41, Ghent B-9000, Belgium.
J Phys Chem B. 2015 Feb 5;119(5):1957-65. doi: 10.1021/jp511378k. Epub 2015 Jan 26.
We investigate the generation of charged inverse micelles in nonpolar surfactant solutions relevant for applications such as electronic ink displays and liquid toners. When a voltage is applied across a thin layer of a nonpolar surfactant solution between planar electrodes, the generation of charged inverse micelles leads to a generation current. From current measurements it appears that such charged inverse micelles generated in the presence of an electric field behave differently compared to those present in equilibrium in the absence of a field. To examine the origin of this difference, transient current measurements in which the applied voltage is suddenly increased are used to measure the mobility and the amount of generated charged inverse micelles. The mobility and the corresponding hydrodynamic size are found to be similar to those of charged inverse micelles present in equilibrium, which indicates that other properties determine their different behavior. The amplitude and shape of the transient currents measured as a function of the surfactant concentration confirm that the charged inverse micelles are generated by bulk disproportionation. A theoretical model based on bulk disproportionation with simulations and analytical approximations is developed to analyze the experimental transient currents.
我们研究了在与电子墨水显示器和液体调色剂等应用相关的非极性表面活性剂溶液中带电反胶束的生成。当在平面电极之间的非极性表面活性剂溶液薄层上施加电压时，带电反胶束的生成会导致产生电流。从电流测量结果来看，在电场存在下生成的这种带电反胶束与在无电场平衡状态下存在的反胶束表现不同。为了研究这种差异的起源，通过突然增加施加电压的瞬态电流测量来测量生成的带电反胶束的迁移率和数量。发现迁移率和相应的流体动力学尺寸与平衡状态下存在的带电反胶束相似，这表明其他性质决定了它们不同的行为。作为表面活性剂浓度函数测量的瞬态电流的幅度和形状证实，带电反胶束是通过本体歧化生成的。基于本体歧化并结合模拟和解析近似建立了一个理论模型，以分析实验瞬态电流。
