Development of Evanescent Wave IR Sensors for Detections of Intermediums and Products in Electrochemistry

• Main Authors: Wan-Ying Shih, 施琬瑩
• Other Authors: Jyisy Yang
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/48511542002318664947

碩士 === 國立中興大學 === 化學系 === 91 === Infrared spectroelectrochemical detection systems provide abundant chemical information for the species generated at the interfacial of the electrodes. Based on the detection mode of infrared spectrometry, several types of spectroelectrochemical cells can be distinguished as the transmission, reflection-absorption, and internal reflection types of cells. The use of transmission type of cells is limited for non-aqueous samples and the capability in detection of the species at the surface of electrode is generally low. For reflection-absorption type of cells, the electrodes should exhibit high reflectivity to increase the sensitivity in detection of the species at the surface of the electrodes. For internal reflection type of cells, the internal reflection element also works as electrode. Therefore, the selection of the materials of electrodes is limited. Meanwhile, special techniques are usually required in the conventional designs. To broaden the application of the infrared spectroelectrochemical detection systems and to improve the weakness in the current detection systems, a new detection system was proposed in this work. This detection system used internal reflection method to detect the chemical species generated from electrochemistry. The electrode materials can be either metals or non-reflective materials such as carbon electrode or surface modified electrodes. Based on the comparison of the obtained IR signals to the literature values for the samples of ferri-/ferro-cyanide and catechol, this proposed detection system is high feasible in detection of electrochemical species existed in the surface of the electrodes. To optimize the detection systems, factors such as cell volume, cell geometry, materials and geometry of electrode were also studied in this work. Results indicated that smaller than 300 mL of the sample volume can be effectively detected and the restriction of material of the electrodes is low.