| 报告题目: | Understanding more in catalysis using combined DFT calculation and isotope labelling experiment |
| 开始时间: | 2018-10-18 15:30:00 |
| 报告地点: | 徐汇校区实验四楼207 |
| 报 告 人: | 南京工业大学 杨艳辉 教授 |
| 主办单位: | 化学与分子工程学院工业催化研究所 |
| 备 注: | 报告人介绍： 杨艳辉， 1974年12月生， 1998年和2001 年在清华大学化工系获得学士和硕士学位， 2003年和2005年于美国耶鲁大学化工系获得硕士和博士学位。 工作经历及社会兼职 2005-2010：新加坡南洋理工大学化工与生物医学工程学院助理教授2010-2017：新加坡南洋理工大学化工与生物医学工程学院副教授（终身教职） 2013-2015：新加坡催化学会副理事长 2016-2017：南京工业大学化学与分子工程学院副院长 2017- 至今：南京工业大学先进化学制造研究院教授，南京工业大学海外教育学院院长， 江苏省特聘教授 科研方向 研究兴趣以物理化学原理为基础、实验技术为手段、模型关联为支撑，研究多相催化剂在能源、环境与有机转化反应等领域的应用。主要研究方向包括基于金属及金属氧化物的多相催化材料用于选择性氧化/加氢反应、纳米材料的合成、生物质转化、二氧化碳活化及能源回收中的应用。科研工作先后得到包括新加坡教育部、科技局，环境署和自然科学基金会的多项资助，发表SCI论文超过200篇，引用7800多次，H-index：44 报告摘要： In the global attempt to reduce carbon footprint, the Chemical and Petrochemical Industry faces the problem to replace the currently used fossil feedstock with renewable resources, reduce energy consumption and to intensify and integrate the processes to be more carbon efficient. In all three issues, catalysis will be the key to a successful transformation. Knowledge-based development and implementation of catalytic technology will help to process the novel feedstock, reduce the energy required for maintaining the desired process and improve the carbon efficiency of the targeted synthesis routes. In this seminar, two examples will be discussed to illustrate our efforts in the exploration of reaction mechanism in heterogeneous catalysis using DFT calculation and isotope labelling experiment.The first example reveals that the surface lattice oxygen of copper oxide activates the formyl C–H bond in glucose and incorporates itself into the glucose molecule to oxidize it to gluconic acid. The reduced CuO catalyst regains its structure, morphology and activity upon re-oxidation. The activity of lattice oxygen is shown to be superior to that of the chemisorbed oxygen on the metal surface and the hydrogen abstraction ability of the catalyst is correlated with the adsorption energy. Based on the present investigation, it is suggested that surface lattice oxygen is critical for the oxidation of glucose to gluconic acid, without further breaking down the glucose molecule into smaller fragments, due to C–C cleavage. Using CuO as the catalyst, excellent yield of gluconic acid is also obtained for the direct oxidation of cellobiose and polymeric cellulose, as biomass substrates. It has been suggested that the dispersion state and the size of metallic particles play a crucial role in determining CO2 conversion and selectivity as well as stability. However, these studies have not considered the possible effect of interface sites between metal and oxide support in selective hydrogenation of CO2. In the second example, three structural configurations of monolayer, periphery and nanocluster in Ru/Al2O3 catalysts were obtained by control of Ru weight loadings, confirmed by the characterization results of the extended X-ray absorption fine structure, H2-O2 titration and diffuse reflectance infrared Fourier transform spectroscopy of CO adsorption. The kinetic data reveal the dependence of reaction rates for CO and CH4 formation with different apparent activation energies on the Ru surface structures. Theoretical calculations of Ru9/Al2O3 and Ru35/Al2O3 models demonstrate that monolayer Ru sites favor the RWGS route with a relatively low energy barrier for both CO2 activation and CO formation steps, while Ru nanoclusters prefer methanation route energetically. Moreover, the combination of theoretical calculations and experimental isotope-exchange measurements suggests that the interfacial O species in Ru-Al2O3 interfaces act a critical role in CO2 activation via exchanging with O atom in feeding CO2 and incorporating into the final hydrogenation products.
(0)
|
