English  |  正體中文  |  简体中文  |  Items with full text/Total items : 6498/11670
Visitors : 25658306      Online Users : 62
RC Version 3.2 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ir.ncue.edu.tw/ir/handle/987654321/16848

Title: Effect of Electron Density of Pt Catalysts Supported on Alkali Titanate Nanotubes in Cinnamaldehyde Hydrogenation
Authors: Hsu, Chin-Yao;Chiu, Tsai-Chin;Shih, Meng-Hung;Tsai, Wei-Je;Chen, Wei-Yi;Lin, Chiu-Hsun
Contributors: 化學系
Date: 2010-03
Issue Date: 2013-06-05T09:36:40Z
Publisher: American Chemical Society
Abstract: Pt nanoparticles of diameter 0.5-1.5 nm were dispersed homogeneously on the inner and outer surfaces of alkali metal titanate nanotubes (M 2Ti3O7, M ) Li+, Na+, and K+) by ion exchange with Pt(NH3)2Cl 2 followed by calcination in ambient air at 673 K and reduction in H2 at 448 K. Both XPS and DRIFTS revealed that these titanate nanotubes donated their electrons to the Pt particles, yielding a negative Pt oxidation state, and that the degree of electron donation increased with the size of the alkali metal cation. The high electron density of the Pt particles promoted the activation of both CdC and CdO functional groups in cinnamaldehyde. Therefore, the order of the catalytic activity in the hydrogenation of cinnamaldehyde was Pt/KTNTs > Pt/ NaTNTs > Pt/LiTNTs. Since the Pt particles were very small, Pt/MTNTs selectively hydrogenated the CdC bond, yielding a hydrocinnamaldehyde with selectivities of 80-87% (at cinnamaldehyde conversions of 27-50%). The alkali metal ions of the titanate nanotubes were able to modify the mode of adsorption of cinnamaldehyde. Therefore, when a KOH promoter was added to the reaction mixture, cinnamyl alcohol became the main product and the cinnamyl alcohol selectivities were 77-83% (at cinnamaldehyde conversions of 49-74%).
Relation: The Journal of Physical Chemistry C, 114(10): 4502-4510
Appears in Collections:[化學系] 期刊論文

Files in This Item:

File SizeFormat

All items in NCUEIR are protected by copyright, with all rights reserved.


DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback