Pd@Pt Bimetallic Catalysts Prepared by Surface-activated Reduction Method and Their Electrochemical Activities

Autor: Wan-Ting Lu, 呂婉婷
Rok vydání: 2009
Druh dokumentu: 學位論文 ; thesis
Popis: 97
A new method to synthesize Pd@Pt core-shell bimetallic catalysts is developed in this research, which is called surface-activated reduction method. The catalyst structures of the synthesized Pd@Pt core-shell bimetallic catalysts are investigated by X-ray Absorption Spectroscopy (XAS) technique. In addition, their correlations between structures and electrochemical activity of oxygen reduction reaction (ORR) as well methanol oxidation reaction (MOR) are also investigated. The synthesized Pd@Pt core-shell bimetallic catalysts have been demonstrated that the structure of particle consists of a Pd-rich core and a Pt-rich shell with average size of 4-5 nm. Their electrochemical results show that the activity of ORR is improved due to electronic effect of Pd. However, the MOR tolerance is also increased because the dehydrogenation reaction is hampered by Pd. Under an appropriate heat-treatment procedure, the tendency of Pt monolayer structure, electrochemical activity and stability of Pd@Pt core-shell bimetallic catalysts are simultaneously and significantly improved.
Databáze: Networked Digital Library of Theses & Dissertations