Tailoring Dielectric Surface Charge via Atomic Layer Thickness
Tailoring Dielectric Surface Charge via Atomic Layer Thickness
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DOI：
10.1021/acsami.9b18444
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发表时间：
2020-01-29
影响因子：
9.5
通讯作者：
Taniguchi, Masateru
中科院分区：
文献类型：
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作者：
Hayashida, Tomoki;Yokota, Kazumichi;Taniguchi, Masateru
通道表面性质是影响单粒子在固态孔隙中捕获-迁移动力学的重要因素。在这里，我们表明，原子级薄的石墨烯可以用来微调孔壁表面电位。我们在Si_3N_4陶瓷上用原子控制厚度的氧化铝进行了同位素涂层。缓冲层中的表面zeta-电位被发现急剧下降1 nm厚的沉积，作为一个透水的超薄片，以调制的有效电荷密度的Al 2 O3/Si 3 N4多层结构。原子层的进一步增厚使得能够以3.4mV/nm分辨率的厚度控制zeta电位。因此，我们观察到伴随的捕获率和带负电荷的聚合物颗粒的易位速度的增强，凭借减轻的电渗透回流在官能化的孔通道。这种简单的方法广泛适用于定制基本上任何传感器和在水介质中工作的设备的表面电荷特性。
Channel surface property is a crucial factor that affects capture-to-translocation dynamics of single-particles in solid-state pores. Here, we show that atomically-thin dielectrics can be used to finely tune the pore wall surface potential. We isotopically coated alumina of atomically controlled thickness on a Si3N4 micropore. The surface zeta-potential in a buffer was found to decrease sharply by 1 nm thick deposition that served as a water-permeable ultra-thin sheet to modulate the effective charge density of the Al2O3/Si3N4 multilayer structure. Further thickening of the atomic layer enabled to control the zeta potential with a thickness at 3.4 mV/nm resolution. Accordingly, we observed concomitant enhancement in the capture rate and the translocation speed of negatively charged polymeric particles by virtue of the mitigated electroosmotic back flow in the functionalized pore channel. This simple method is widely applicable for tailoring the surface charge properties of essentially any sensors and devices working in aqueous media.