Fabrication of Homogeneously-structured PtIr Bimetallic Nano-Catalyst/Glucose Oxidase Composite Electrode and its Applications

• Main Authors: Min-Hsin Yeh, 葉旻鑫
• Other Authors: Bing-Joe Hwang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/75437610847365454270

碩士 === 國立臺灣科技大學 === 化學工程系 === 97 === This investigation mainly consists of two topics: (a) development of novel, bimetallic nanocatalyst PtIr/C and employing nanocatalyst in hydrogen peroxide oxidation reaction (HOPR). (b) Fabrication of the mini-biosensor with the homogeneous catalyst/enzyme composite structure by electrophoresis deposition (EPD) method. The crystalline and particle size of nanocatalyst were investigated by XRD and TEM, respectively. The catalytic activity was obtained by the amperometric determination of HOPR. The studies of synchrotron based- X ray absorption spectroscopy (XAS) and density functional theory (DFT) calculation demonstrated that the addition of Ir atom modify the d band electronic configuration of Pt atom and enhance the nanocatalyst functionality, consequently promote the HOPR activity. Furthermore, the HOPR mechanism on the catalyst surface has been proposed and the “deprotonation“step was considered to be rate determining step via this investigation. Moreover, EPD method has been employed to simultaneously deposit the nanocatalyst and enzyme onto the electrode surface. The depth profile analysis of ESCA provided the evidences that EPD method enables to create the homogeneous nanocatalyst/enzyme composite domain. The long term stability and the low value of Michaelis-Menten constant ( Kmapp =5.68 mM ) revealed that the composite matrix provide a stable and three dimensions structure. After the parameter optimization, the fabricated mini-biosensor showed a linear detection of glucose ranges from 2 mM to 20 mM with a detection limit of 0.1 mM and the maximal sensitivity of 2.89 μA/mM．cm2 (R2=0.995, R.S.D. =3.26%, N=3). Overall, EPD method has been used for fabricating the homogeneous nanocatalyst/enzyme composite mini-biosensor with favorable reproducibility, stability and accuracy.