论文标题
通过电沉积的银纳米线的模板辅助生长
Template-assisted growth of silver nanowires by electrodeposition
论文作者
论文摘要
模板辅助合成是种植各种一维纳米结构的一种便捷方式。在各种纳米多孔模板中，最常用的是氧化氧化铝（AAO）。在这项工作中，研究了AAO模板中电沉积的银纳米线生长动力学。使用标准的两步阳极氧化过程制造了AAO模板。使用扫描电子显微镜获得了制造模板的几何特征，例如孔径（55 nm），孔间距离（115 nm），壁厚（27 nm），孔隙率（19.87％）和孔密度。孔底部的氧化物层通过屏障层变薄和化学蚀刻来修饰，以促进均匀的金属沉积。随后，孔扩大以将孔的直径增加到65 nm，以增强沉积。室间距离增加到119.8 nm，壁厚厚度在27.7 nm处保持恒定。用常规电沉积在恒定电流模式下沉积银。系统研究了沉积参数，例如时间，电流，溶液浓度和温度。对于每次沉积，通过考虑孔的填充分数和电线的平均长度来计算过程的效率，所有这些效率都是从SEM图像中测量的。在参数范围内观察到线性生长与时间。从实验中，可以观察到降低电流，升高沉积温度并延长持续时间增加纳米线的平均长度。使用电沉积来生长金属纳米线可以扩展到其他纯金和合金系统。
Template-assisted synthesis is a facile way of growing various one-dimensional nanostructures. Among various nanoporous templates, anodic aluminium oxide (AAO) is most commonly used. In this work, the kinetics of silver nanowire growth by electrodeposition in AAO templates was investigated. The AAO templates were fabricated using the standard two-step anodisation process. The geometrical features of the fabricated templates, such as pore diameter (55 nm), interpore distance (115 nm), wall thickness (27 nm), porosity (19.87 %), and pore density were obtained using scanning electron microscopy. The oxide layer at the bottom of the pores was modified by the barrier layer thinning process and chemical etching in order to facilitate uniform metal deposition. This was followed by pore widening to increase the diameter of the pores to 65 nm to enhance deposition. Interpore distance increased to 119.8 nm and wall thickness remained almost constant at 27.7 nm. Silver was deposited using conventional electrodeposition in constant current mode. Deposition parameters such as time, current, solution concentration, and temperature were systematically investigated. For each deposition, the efficiency of the process was calculated by considering the filling fraction of the pores and the average length of the wires, all of which were measured from the SEM images. A linear growth versus time was observed within the parameter range. From the experiments, it was observed that decreasing the current, increasing the deposition temperature, and depositing for longer duration increased the average length of the nanowires. The use of electrodeposition to grow metallic nanowires can be extended to other pure metal and alloy systems.
