高等学校化学学报 ›› 2013, Vol. 34 ›› Issue (8): 1936.doi: 10.7503/cjcu20130137

• 物理化学 • 上一篇    下一篇

新型核壳结构纳米催化剂的三效催化活性及热稳定性

刘北北, 张桂臻, 何洪, 李金洲, 訾学红, 邱文革, 戴洪兴   

  1. 北京工业大学环境与能源工程学院化学化工系催化化学与纳米科学研究室, 北京 100124
  • 收稿日期:2013-02-06 出版日期:2013-08-10 发布日期:2013-07-19
  • 通讯作者: 何洪,男,博士,教授,主要从事催化化学和纳米催化的研究.E-mail:hehong@bjut.edu.cn E-mail:hehong@bjut.edu.cn
  • 基金资助:

    国家稀土稀有金属新材料和产业化专项——高性能稀土基汽车尾气催化器研发及国V催化器产业化、 北京市自然科学基金(批准号: 2101002); 国家自然科学基金(批准号: 21007002); 国家"八六三"计划项目(批准号: 2011AA03A40)和北京市创新团队项目(批准号: PHR201107104)资助.

Three-way Catalytic Acitvities and Thermal Stabilities of Pd@SiO2/Ce0.4Zr0.6O2 Nanocatalysts with Core-shell Structure

LIU Bei-Bei, ZHANG Gui-Zhen, HE Hong, LI Jin-Zhou, ZI Xue-Hong, QIU Wen-Ge, DAI Hong-Xing   

  1. Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
  • Received:2013-02-06 Online:2013-08-10 Published:2013-07-19
  • Contact: Gui-Zhen Zhang E-mail:hehong@bjut.edu.cn

摘要:

从Pd纳米粒子出发制备了具有核壳结构的新型纳米Pd@SiO2/Ce0.4Zr0.6O2三效催化剂及作为参比的Pd/Ce0.4Zr0.6O2催化剂, 采用X射线衍射、 透射电子显微镜、 氢气程序升温还原和氮气低温吸附-脱附等技术对催化剂的物化性质进行了表征, 研究了Pd@SiO2/Ce0.4Zr0.6O2和Pd/Ce0.4Zr0.6O2催化剂的三效反应催化活性和热稳定性. 结果表明, SiO2壳层可以抑制Pd粒子的团聚, 同时还能抑制Pd物种的再分散, 减少Pd的流失. 具有核壳结构的纳米Pd@SiO2/Ce0.4Zr0.6O2催化剂具有更好的三效催化活性和更高的热稳定性.

关键词: 核-壳结构, 三效催化剂, 钯, 二氧化硅, 热稳定性

Abstract:

A New type of Pd@SiO2/Ce0.4Zr0.6O2 three-way nanocatalyst with core-shell structure was prepared from the colloidal Pd nanoparticles. For comparison, the corresponding reference catalyst Pd/Ce0.4Zr0.6O2 was synthesized. The catalysts were characterized by powder X-ray diffraction(XRD), transmission electron microscopy(TEM), nitrogen gas adsorption-desorption and temperature programmed reduction by H2(H2-TPR). The three-way catalytic activities and the thermal stabilities of the two kinds of catalysts with different structure were investigated. It was found that the silica shell could prevent the aggregation of Pd nanoparticles. At the same time, the silica could inhibit the redispersion of Pd species so that the loss of precious metal Pd was reduced. All results showed that the Pd@SiO2/Ce0.4Zr0.6O2 nanocatalyst with core-shell structure possessed good three-way catalytic activities and high thermal stabilities.

Key words: Core-shell structure, Three-way catalyst, Palladium, Silica, Thermal stability

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