%0 Journal Article %T
%A 刘敬伟 %A 杨娜婷 %A 祝艳 %J 物理化学学报 %D 2017 %R 10.3866/PKU.WHXB201704104 %X 我们报道了一种Pd/Co3O4纳米颗粒负载于Al2O3纳米片的三元催化剂催化甲烷的高效燃烧。其中,Pd/Co3O4负载于碱性氧化铝的复合材料活化甲烷C-H键的能力比SiO2、ZrO2和CeO2以及酸性和中性Al2O3为载体时更强,这是因为Pd/Co3O4/碱性Al2O3拥有更多的氧空穴和吸附氧,对催化剂催化甲烷燃烧有较好的影响。尽管在5%(体积分数)的水蒸气存在下,其催化性能有一定的失活,但在移除水蒸气时,其催化性能可以快速恢复至最佳状态。在模拟真实汽车尾气的氛围下,Pd/Co3O4/碱性Al2O3依然具有较好的催化甲烷燃烧性能,在400℃时可以催化甲烷完全转化。
We report an efficient catalyst composed of ternary components prepared by inlaying Pd/Co3O4 nanoparticles in alkaline Al2O3 nanosheets for catalytic oxidation of methane. Pd/Co3O4 inlaid in alkaline Al2O3 exhibited a higher ability to break the C-H bond of methane than Pd/Co3O4 supported on SiO2, ZrO2, CeO2, and acidic or neutral Al2O3. Our results show more oxygen vacancies and higher amounts of surface adsorbed oxygen on the surface of Pd/Co3O4/alkaline Al2O3 than on other catalysts, which is responsible for methane activation and conversion. Further, the Pd/Co3O4/alkaline Al2O3 catalyst can almost restore to its initial value in the absence of water when 5% (volume fraction) vapor water was cut off, although a decrease in activity occurred when water vapor was introduced to the reaction system. Even under a condition similar to the exhaust of a lean-burn natural gas engine, the catalytic performance of the Pd/Co3O4/alkaline Al2O3 catalyst is excellent, that is, methane could be completely converted when the sample temperature in the reaction atmosphere was ramped to 400℃ %U http://www.whxb.pku.edu.cn/CN/Y2017/V33/I7/1453