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JMCA: Ultrafine platinum/iron oxide nanoconjugates confined in silica nanoshells, by Hongyu et al
发布者: 高传博 | 2015-12-17

 

Hongyu's work on ultrafine Pt/FeOx nanoconjugates in silica nanoshells for highly durable catalytic oxidation reactions has been published by Journal of Materials Chemistry A. Congratulations!

Title: Ultrafine platinum/iron oxide nanoconjugates confined in silica nanoshells for highly-durable catalytic oxidation

Authors:  H. Zhao, D. Wang, C. Gao*, H. Liu*, L. Han, Y. Yin*

Link to the publisher:  http://pubs.rsc.org/en/content/articlelanding/2015/ta/c5ta09215a

 

Abstract: Noble metal/transition metal (hydr)oxide interfaces are often highly active catalytic sites for many oxidation reactions. One of the challenges in such catalyst systems especially in high-temperature reactions is a lack of effective mechanism to stabilize the catalysts against sintering over time and to maintain the metal/oxide interfaces. Herein, we report an alloying-dealloying process for the production of ultrafine Pt/FeOx nanoconjugates (~1.8 nm) with confinement in silica nanoshells for effective stabilization. The synthesis started with coating of ultrasmall Pt/Fe precursor nanoparticles in reverse micelles by a microporous silica shell, which served as a nanoreactor to allow the subsequent transformation of the precursor nanoparticles into the target Pt/FeOx nanoconjugates. Thanks to the ultrasmall size of the nanoconjugates and their effective protection by the silica shells, the resulting Pt/FeOx@SiO2 yolk/shell nanospheres showed high catalytic activity and remarkable durability in preferential CO oxidation in H2 (PROX). This synthesis strategy may represent a general approach in rational design of highly stable catalysts with complex nanostructures for a broad range of catalysis.


中文摘要:

近年来人们发现贵金属/过渡金属氧化物界面(NM/TMO)是很多氧化反应的活性位点。该类催化剂一般负载在氧化硅等载体的表面,因此很容易发生团聚失活的现象。本工作以纳米氧化硅空心球(约20nm)为微反应器,在其中实现了Pt和Fe的合金化和氧化去合金化反应,得到了被微孔氧化硅包裹的Pt/FeOx异质结构纳米粒子(约1.8 nm)。该材料在富氢条件下的CO氧化反应(PROX)中显示出很高的活性和稳定性,可用于氢燃料电池的气体前处理过程。该合成路线为异质结构纳米催化剂的制备和稳定化提供了一条通用的途径。

本工作是在国家自然科学基金和西安交通大学启动经费等支持下完成的,论文发表在纳米催化领域权威期刊Journal of Materials Chemistry A(影响因子:8.262)上。