Photoluminescence of Zinc Oxide Nanowires Grown with Gold Catalyst

• Main Authors: Ke-Wei Chen, 陳可緯
• Other Authors: Ching-Ling Hsu
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/94070093043595560363

碩士 === 中原大學 === 物理研究所 === 101 === In this experiment, ZnO nanowires were grown on Si (111) substrates by the carbon thermal reduction method with catalytic gold nanoparticles or thin films. The diameters of the nanowires were about 70 ~ 90 nm. Due to that the nanowires were entangled with each other, we could not determine the lengths of nanowire from the scanning electron microscopy (SEM) images accurately. However, the lengths were observed in the order of magnitude of 10-5 m. In the photoluminescence (PL) spectra, all samples showed that the peak of the near-band edge emission (UV) has a red-shift with the increased excitation power. The red-shift range is from 377 nm to 407 nm. It may be because the dominate carrier behavior was mainly from electron-hole plasma instead of excitons. The dependence between the PL intensity and the excitation power follows the power law. The α value (exponent) for the UV emission is from 1.387 to 1.979; The α value of the visible emission is from 0.471 to 0.807. These data show that the light scattering behavior and the specific surface area of our samples was similar to those of the nanorods and microparticles studied in the previous literatures. The α value of the ratio of the UV intensity to the visible intensity shows that the quality of the samples cannot be judged by one single excitation power spectrum. The wide range of the α values shows that some factors may still not be well controlled in the growth of nanowires.