摘要
以有序的中孔炭材料CMK-3为模板,以硝酸铈为前体,利用纳米铸型法合成了具有规则结构的中孔氧化铈,考察了模板脱除温度对中孔氧化铈微结构的影响.热重、元素分析、X射线衍射、透射电镜和氮气物理吸附结果表明,炭模板的脱除温度可低至350oC,所得氧化铈具有二维六方规则结构,比表面积高达167m2/g,孔径分布集中在3~5nm.采用胶体沉积法将2~5nm的金溶胶粒子沉积到所得氧化铈表面制得了Au/CeO2催化剂,考察了Au/CeO2在CO氧化反应中的活性.结果表明,该催化剂的活性较常规氧化铈制备的金催化剂有明显提高,这可能与载体的规则结构有关.
Ordered mesoporous ceria oxides (CeO2) were synthesized by nanocasting using ordered mesoporous carbon (CMK-3) as the template and cerium nitrate as the CeO2 precursor. The as-prepared materials were characterized by thermogravimetry, elemental analysis, powder X-ray diffraction, transmission electron microscopy, and N2 adsorption. The obtained ceria exhibits a 2-D hexagonal ordered structure with a high surface area of up to 167 m^2/g and pore size in the range of 3-5 nm. The carbon template can be completely removed at a temperature as low as 350 ℃. Such ceria was then employed as the support for the preparation of gold catalysts by the colloid deposition method. The catalytic activity of the Au/CeO2 catalyst was evaluated in CO oxidation. An enhanced catalytic activity was observed over such a catalyst possibly due to the nano-sized particle and narrow pore size of the ordered mesoporous ceria.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第11期1085-1090,共6页
基金
Supported by the Key Project of the Chinese Ministry of Education (108138)
the Basic Funding of Dalian University of Tech-nology (DUT)
关键词
氧化铈
炭模板
纳米铸型
金
一氧化碳
氧化
ceria
carbon template
nanocasting
gold
carbon monoxide
oxidation