A Highly Porous Carbon Support Rich in Graphitic‐N Stabilizes Copper Nanocatalysts for Efficient Ethanol Dehydrogenation
A Highly Porous Carbon Support Rich in Graphitic‐N Stabilizes Copper Nanocatalysts for Efficient Ethanol Dehydrogenation
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DOI：
10.1002/cctc.201601373
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发表时间：
2017-02
期刊：
影响因子：
4.5
通讯作者：
Peng Zhang;Qing-Nan Wang;Xia Yang;Dongqi Wang;Wen‐Cui Li;Yanping Zheng;Mingshu Chen;An‐Hui Lu-An‐
中科院分区：
文献类型：
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作者：
Peng Zhang;Qing-Nan Wang;Xia Yang;Dongqi Wang;Wen‐Cui Li;Yanping Zheng;Mingshu Chen;An‐Hui Lu-An‐
由于原子经济转化和产物易于分离，生物乙醇脱氢为乙醛和氢气是一个可持续的过程。然而，氧化物负载的Cu催化剂显示出对乙醛的低选择性，因为它们的富氧表面引起相当多的副反应。传统的碳载Cu催化剂显示出高选择性，但由于铜颗粒的迁移和团聚而迅速失活。在这里，我们已经生产了一种高度多孔的富氮碳载体，其含有6.2重量%的N，并且可以很好地分散和稳定Cu纳米颗粒（约6.3 nm）。如果用于乙醇脱氢，乙醛的选择性约为98%，具有长达500 min的优异抗团聚能力。X射线光电子能谱（XPS）数据证明，电子从N位转移到Cu颗粒。理论计算进一步表明，氮位点增强了Cu 2 O簇的吸附，并且可以稳定它们以防止聚结，并且石墨-N位点（约占总N含量的40%）是最重要的。
The dehydrogenation of bioethanol to acetaldehyde and hydrogen is a sustainable process, owing to the atom‐economical transformation and easy separation of the products. However, oxide‐supported Cu catalysts show a low selectivity to acetaldehyde because of considerable side reactions caused by their oxygen‐rich surfaces. A conventional carbon‐supported Cu catalyst shows high selectivity, but is quickly deactivated owing to the migration and agglomeration of copper particles. Here, we have produced a highly porous nitrogen‐rich carbon support that contains 6.2 wt % N and can nicely disperse and stabilize Cu nanoparticles (∼6.3 nm). If used for ethanol dehydrogenation, approximately 98 % selectivity to acetaldehyde has been achieved, with excellent anti‐agglomeration ability for as long as 500 min. X‐ray photoelectron spectroscopy (XPS) data prove that electrons transfer to the Cu particles from the N sites. Theoretical calculations further show that nitrogen sites enhance the adsorption of Cu20 clusters and can stabilize them against coalescence and that graphitic‐N sites (approximately 40 % of total N content) are the most significant.