Promoted CO oxidation activity in the presence and absence of hydrogen over the TiO2-supported Pt/Co-B bicomponent catalyst
Promoted CO oxidation activity in the presence and absence of hydrogen over the TiO2-supported Pt/Co-B bicomponent catalyst
复制标题
在存在和不存在氢气的情况下，TiO2 负载的 Pt/Co-B 双组分催化剂可促进 CO 氧化活性
DOI：
10.1016/j.apcatb.2010.10.001
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发表时间：
2011-01-14
影响因子：
22.1
通讯作者：
Fu, Xianzhi
中科院分区：
文献类型：
--
作者：
Ding, Zhengxin;Yang, Haiyan;Fu, Xianzhi
采用两步浸渍-还原法制备了Pt/Co-B/TiO 2催化剂。该Pt/Co-B/TiO_2催化剂在无H-2存在下对CO的氧化活性和在有H-2存在下对CO的优先氧化活性均高于由H-2还原制备的Pt/Co双组分催化剂（Pt/Co/TiO_2）。基于X射线光电子能谱分析、CO在不同催化剂上的吸附和Co-B的密度泛函计算结果，提出了非晶态结构的Co-B中电子从B转移到Co原子上可能是促进CO在Pt/Co-B/TiO 2上氧化的原因.这种电子转移通过抑制Pt向Co原子的电子转移，可以保持Pt/Co-B/TiO 2中Pt的高表面电子密度，有利于Pt表面吸附的CO物种的活化。(c)2010爱思唯尔有限公司版权所有。
A Pt and Co-B bicomponent catalyst supported on TiO2 (Pt/Co-B/TiO2) is prepared by a two-step impregnation-reduction method. This Pt/Co-B/TiO2 catalyst exhibits a higher activity for CO oxidation in the absence of H-2 and for preferential CO oxidation in the presence of H-2, as compared to the Pt/Co bimetallic component catalyst (Pt/Co/TiO2) prepared by H-2 reduction. Based on the results of the X-ray photoelectron spectroscopy analysis, the CO adsorption over different catalysts and the density functional computation of Co-B, it is proposed that the electron transfer from B to Co atoms in Co-B with an amorphous structure may be responsible for the promoted oxidation of CO over Pt/Co-B/TiO2. This electron transfer can keep a high surface electron density of Pt in Pt/Co-B/TiO2 via inhibiting the electron transfer from Pt to Co atoms, which is favorable for the activation of CO species adsorbed at Pt surface. (c) 2010 Elsevier B.V. All rights reserved.