Mechanistic investigation of ethanol oxidation reaction on PtSn bimetals

• Main Authors: Tseng, Yen-Cheng, 曾彥程
• Other Authors: Wang, Jeng-Han
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/2hcukk

碩士 === 國立臺灣師範大學 === 化學系 === 106 === The present study investigates ethanol oxidation reactions (EOR), the anodic reactions for direct ethanol fuel cells (DDEFC), on Pt and PtSn alloys with the ratios of Pt/Sn = 10/1, 5/1, 3/1, 1/1 and 1/3 (Pt¬10Sn1, Pt¬5Sn1, Pt¬3Sn1, Pt¬1Sn1, Pt¬1Sn3) on carbon black XC-72. All bimetallic catalysts are synthesized by impregation method and characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) to confirm the cystal structure, composition and oxidation state of each element. The fabricated catalysts have been examined by the electrochemical tests of cyclic voltammetry (CV) and chronoamperometry (CA) to study the ECSA, EOR activity and stability. Furthermore, we employed in situ FTIR to investigate the product evolution in the reaction for the mechanism understanding. The experimental observation found that proper amount of Sn addition can change the oxidation state of Pt to strengthen the ethanol adsorption and improve the EOR activity and stability. As a result, Pt5Sn1 has the best EOR performance. Additionally, the FTIR spectra show the main product on those PtSn bimentals is acetic acid corresponding to the four – electron – oxidation pathway.