Xie Yanbo, Xue Jianming, Wang Lin, Wang Xinwei, Jin Ke, Chen Long, Wang Yugang
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Center for Applied Physics and Technology, Peking University, Beijing, PR China.
Langmuir. 2009 Aug 18;25(16):8870-4. doi: 10.1021/la9017213.
In this letter, we report a method to modify the surface charge property of single track-etched nanopores with a cationic surfactant (CTAB). The dependence of surface charge density on the surfactant concentration was investigated by measuring the streaming current when the nanopore was immersed in 0.01 M KCl solution with different CTAB concentrations. The results showed that, when the concentration of CTAB was increased gradually, the surface charge of the nanopore was inverted from negative to positive. Our calculation indicated that the surface charge density changed from -9 to 8 mC/m2. We utilized this method to modify the surface property of single conical track-etched nanopores. Its current rectification properties (both the direction and magnitude) were successfully tuned by adjusting the CTAB concentration in the solutions.
在这封信中，我们报告了一种用阳离子表面活性剂（十六烷基三甲基溴化铵，CTAB）修饰单径迹蚀刻纳米孔表面电荷性质的方法。通过测量纳米孔浸入不同CTAB浓度的0.01 M KCl溶液中的流动电流，研究了表面电荷密度对表面活性剂浓度的依赖性。结果表明，当CTAB浓度逐渐增加时，纳米孔的表面电荷从负变为正。我们的计算表明，表面电荷密度从-9变为8 mC/m²。我们利用这种方法修饰了单锥形径迹蚀刻纳米孔的表面性质。通过调节溶液中的CTAB浓度，成功地调整了其电流整流特性（方向和大小）。
