Kunwar Sundar, Sui Mao, Zhang Quanzhen, Pandey Puran, Li Ming-Yu, Lee Jihoon
1College of Electronics and Information, Kwangwoon University, Nowon-gu, Seoul, 01897 South Korea.
2Institute of Nanoscale Science and Engineering, University of Arkansas, Fayetteville, AR 72701 USA.
Nanomicro Lett. 2017;9(2):17. doi: 10.1007/s40820-016-0120-6. Epub 2016 Nov 28.
Silver (Ag) nanostructures demonstrate outstanding optical, electrical, magnetic, and catalytic properties and are utilized in photonic, energy, sensors, and biomedical devices. The target application and the performance can be inherently tuned by control of configuration, shape, and size of Ag nanostructures. In this work, we demonstrate the systematical fabrication of various configurations of Ag nanostructures on sapphire (0001) by controlling the Ag deposition thickness at different annealing environments in a plasma ion coater. In particular, the evolution of Ag particles (between 2 and 20 nm), irregular nanoclusters (between 30 and 60 nm), and nanocluster networks (between 80 and 200 nm) are found be depended on the thickness of Ag thin film. The results were systematically analyzed and explained based on the solid-state dewetting, surface diffusion, Volmer-Weber growth model, coalescence, and surface energy minimization mechanism. The growth behavior of Ag nanostructures is remarkably differentiated at higher annealing temperature (750 °C) due to the sublimation and temperature-dependent characteristic of dewetting process. In addition, Raman and reflectance spectra analyses reveal that optical properties of Ag nanostructures depend on their morphology.
银（Ag）纳米结构具有出色的光学、电学、磁学和催化性能，被应用于光子学、能源、传感器和生物医学设备中。通过控制银纳米结构的构型、形状和尺寸，可以固有地调整其目标应用和性能。在这项工作中，我们展示了通过在等离子体离子镀膜机中不同退火环境下控制银的沉积厚度，在蓝宝石（0001）上系统地制备各种构型的银纳米结构。特别地，发现银颗粒（2至20纳米）、不规则纳米团簇（30至60纳米）和纳米团簇网络（80至200纳米）的演变取决于银薄膜的厚度。基于固态去湿、表面扩散、伏尔默 - 韦伯生长模型、聚结和表面能最小化机制，对结果进行了系统分析和解释。由于去湿过程的升华和温度依赖性特征，在较高退火温度（750°C）下，银纳米结构的生长行为有显著差异。此外，拉曼光谱和反射光谱分析表明，银纳米结构的光学性质取决于其形态。
