Development of Nanosized-Platinum Deposited Titanium Dioxide for Electroanalytical Applications

• Main Authors: Ya-Han Tsai, 蔡雅涵
• Other Authors: 曾志明
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/4bpv2d

碩士 === 國立中興大學 === 化學系所 === 101 === The thesis is divided into two major parts. The first part focuses on the development of composite platinum nanoparticles -titanium dioxide (PtNP/TiO2) and the second part deals with its application as an electrochemical sensor. We use hexachloroplatinic acid solution (H2PtCl6) as a precursor in photo- reduction of platinum nanoparticles on TiO2. In order to understand the best condition for the fabrication of PtNP/TiO2, the influences of pH values, Pt and titanium dioxide concentration were investigated. Both Transmission Electron Microscopy (TEM) and Energy Dispersive Spectrometer (EDS) studies were used to analyze the morphology as well as the size of Pt nanoparticles deposited on TiO2. Well-defined Pt nanoparticles with the size of ~5 nm were distributed on the surface of TiO2 as confirmed from the TEM images. Previous works addressed about the preparation of platinum nanoparticles on TiO2, with the addition of reducing reagents (like NaBH4 and sodium citrate) or organic solvents in the process, some methods even need heating to accelerate the reduction rate of metal nanoparticles, and also use complicated process of annealing or calcination at high temperature for making platinum nanoparticles on the surface of TiO2. Compared to these works, the advantages of our proposed method are no complicated process involved or heating while in the preparation step without the addition of any reducing agents. The second part of this study aimed at the electrochemical applications of the PtNP/TiO2. The PtNP/TiO2 modified screen-printed carbon electrode (PtNP/TiO2-SPCE) displayed good electrocatalytic ability for dissolved oxygen (DO) measurement and the direct electrochemical oxidation of glucose. The DO measurement by the PtNP/TiO2-SPCE displayed good linearity with that of a commercial DO meter indicating that the proposed system can be used as a promising O2 sensor. Besides, combination of the PtNP/TiO2-SPCE and amperometry was used for the determination of glucose. The calibration plot was obtained in the range of 10 μM－3 mM glucose (r2 = 0.998) with a sensitivity of 20.084 μA mM–1 cm–2 and the lowest detection limit of 0.46 μM (S/N = 3). And this detection method could avoid the interference of the interferant such as Uric acid, L(+)-Ascorbic acid, and Acetaminophen. Overall, we present a simple method for the preparation of titanium dioxide supported platinum catalyst for use as a sensor with good sensitivity, wide linear range, and good stability, showing excellent electrocatalytic activity and practicability towards detection of both O2 and glucose.