Electrochemical synthesis of flower-like silver microstructures and their applications in surface-enhanced Raman spectroscopy

• Main Author: 唐群
• Other Authors: 林泱蔚
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/63832647570080784959

碩士 === 國立彰化師範大學 === 化學系 === 103 === In this work, flower-like silver microstructures deposited on screen printed carbon electrode were prepared by using electrochemical method. A screen-printed carbon electrode, a silver - silver chloride (Ag/AgCl) electrode, a platinum wire were employed as the working, reference, and counter electrode, respectively. The screen-printed electrode was cycled in silver nitrate solution containg silver nanoparticles from -0.3 to +0.2 V vs Ag/AgCl at 1.25 mV/s for seven scans. Ths size of the flower-like silver microstructure is approximately 4.29 ± 6 μm, and each of them possess many micro structures (4.0 ± 0.3 μm) obtained by scanning electron microcopy. Using 4-mercaptobenzoic acid (4-MBA) as a Raman reporter, 532 nm laser as an excitation light source, the flower-like silver substrate is explored by Raman microscopy. We found that the Raman signals of 4-MBA with the flower-like silver substrate are 150 time higher than those with the traditional silver substrate. The enhance factor is 1.23 x106, due to its roughed surface and mesostructures, leading to the electromagnetic enhancements. Furthermore, the Raman signals of 5,5'-dithiobis-(2-nitrobenzoic acid), 4-Aminobenzenethiol, adenine, Cy3 modified DNA molecules were observed. The flower-like silver microstructures, with advantages of facile farbrication, good reproducibility (RSD 2.1%), excellence thermal stability (100 oC), and durability (54 days), show the potentials for the applications in chemical and biological detection.