Three-dimensionally ordered mesoporous Co3O4-supported Au-Pd alloy nanoparticles: High-performance catalysts for methane combustion
Three-dimensionally ordered mesoporous Co3O4-supported Au-Pd alloy nanoparticles: High-performance catalysts for methane combustion
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DOI：
10.1016/j.jcat.2015.09.008
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发表时间：
2015-12-01
影响因子：
7.3
通讯作者：
Dai, Hongxing
中科院分区：
文献类型：
--
作者：
Wu, Zhixing;Deng, Jiguang;Dai, Hongxing
使用 KIT-6 模板和聚乙烯醇保护制备了三维有序介孔 Co3O4 (meso-Co3O4) 及其负载的 Au、Pd 和 Au-Pd 合金 (xAu(y)Pd/meso-Co3O4; x = 0.43-2.94 wt%; Au/Pd 摩尔比 (y) = 0.43-0.50）纳米催化剂分别采用减少方法。结果发现，内消旋Co3O4具有106 m(2)/g的高比表面积，其晶体结构为立方体，尺寸为2.7-4.5 nm的贵金属纳米颗粒(NPs)均匀分散在内消旋Co3O4表面。 2.94Au(0.50)Pd/meso-Co3O4 样品在甲烷燃烧方面表现最好，在 20,000 mL/(g h) 的空速下显示出 T-10%、T-50% 和 T-90%（实现甲烷转化率 10%、50% 和 90% 所需的温度）分别为 230、280 和 324 摄氏度，最低表观活化能为 44.4 kJ/mol。此外，还考察了CO2、SO2和H2O的添加对2.94Au(0.50)Pd/meso-Co3O4催化稳定性的影响。结果表明，2.94Au(0.50)Pd/meso-Co3O4优异的催化性能与其多孔结构、高吸附氧浓度、良好的低温还原性以及Au-Pd合金纳米粒子与meso-Co3O4之间的强相互作用有关。 (C) 2015 Elsevier Inc. 保留所有权利。
Three-dimensionally ordered mesoporous Co3O4 (meso-Co3O4) and its supported Au, Pd, and Au-Pd alloy (xAu(y)Pd/meso-Co3O4; x = 0.43-2.94 wt%; Au/Pd molar ratio (y) = 0.43-0.50) nanocatalysts were prepared using the KIT-6-templating and polyvinyl alcohol-protected reduction methods, respectively. It is found that the meso-Co3O4 with a high surface area of 106 m(2)/g was cubic in crystal structure and the noble metal nanoparticles (NPs) with a size of 2.7-4.5 nm were uniformly dispersed on the surface of meso-Co3O4. The 2.94Au(0.50)Pd/meso-Co3O4 sample performed the best for methane combustion, showing the T-10%, T-50%, and T-90% (temperatures required for achieving methane conversions of 10%, 50%, and 90%) of 230, 280, and 324 degrees C at a space velocity of 20,000 mL/(g h) and the lowest apparent activation energy of 44.4 kJ/mol. Furthermore, the effects of CO2, SO2, and H2O addition on the catalytic stability of 2.94Au(0.50)Pd/meso-Co3O4 were also examined. It is concluded that the excellent catalytic performance of 2.94Au(0.50)Pd/meso-Co3O4 was associated with its porous structure, high adsorbed oxygen species concentration, good low-temperature reducibility, and strong interaction between Au-Pd alloy NPs and meso-Co3O4. (C) 2015 Elsevier Inc. All rights reserved.