Study of gas sensing application using molecule modified gold particle films

• Main Authors: Yu-Kai Liu, 劉宇凱
• Other Authors: Shien-Der Tzeng
• Format: Others
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/cs5jb8

碩士 === 國立東華大學 === 物理學系 === 100 === In this work, we study the application of molecule modified gold nanoparticle films to gas sensing. We used Heme B, 11-Mercaptoundecanoic acid (MUA), and 8-Mercaptooctanoic acid (MOA) molecules to modify the surfaces of gold nanoparticles, and form gold nanoparticle films by centrifuge assembly method. The films with different molecules were put in a chamber with N2, O2, CO, or H2O gas. We found that the current passing through the film under a constant bias would change with the gas pressure. For Heme B sample, when the pressure changed from 0.1 to 10 torr, the change of current were 2.8±0.9%, 3.0±1.5%, 7.4±2.1%, and 16.0±3.0% in N2, O2, CO, and H2O gas, respectively. For MUA sample, they were 2.3±1.5%, 1.7±0.2%, 2.8±0.5%, and 3.1±1.2%, respectively. For MOA sample, they were 4.1±0.2%, 2.9±0.9%, 2.4±0.6%, and 2.8±0.9%, respectively. These results show that Heme B sample was more sensitive for CO gas than O2 gas. However Heme B sample was most sensitive in H2O gas. Therefor, the influence of humidity should be compensate when sensing CO gas by using Heme B sample.