Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155, USA.
Thomas Young Centre and Department of Chemical Engineering, University College London, Roberts Building, Torrington Place, London WC1E 7JE, UK.
Nat Chem. 2018 Mar;10(3):325-332. doi: 10.1038/nchem.2915. Epub 2018 Jan 8.
The recent availability of shale gas has led to a renewed interest in C-H bond activation as the first step towards the synthesis of fuels and fine chemicals. Heterogeneous catalysts based on Ni and Pt can perform this chemistry, but deactivate easily due to coke formation. Cu-based catalysts are not practical due to high C-H activation barriers, but their weaker binding to adsorbates offers resilience to coking. Using Pt/Cu single-atom alloys (SAAs), we examine C-H activation in a number of systems including methyl groups, methane and butane using a combination of simulations, surface science and catalysis studies. We find that Pt/Cu SAAs activate C-H bonds more efficiently than Cu, are stable for days under realistic operating conditions, and avoid the problem of coking typically encountered with Pt. Pt/Cu SAAs therefore offer a new approach to coke-resistant C-H activation chemistry, with the added economic benefit that the precious metal is diluted at the atomic limit.
最近页岩气的可用性使得人们对 C-H 键活化重新产生了兴趣，因为这是合成燃料和精细化学品的第一步。基于 Ni 和 Pt 的多相催化剂可以进行这种化学转化，但由于积碳的形成而容易失活。由于 C-H 活化势垒较高，Cu 基催化剂并不实用，但由于其对吸附物的结合较弱，因此对结焦具有弹性。我们使用 Pt/Cu 单原子合金（SAA），通过模拟、表面科学和催化研究相结合的方式，在包括甲基、甲烷和丁烷在内的多个体系中研究了 C-H 键的活化。我们发现，Pt/Cu SAA 比 Cu 更有效地活化 C-H 键，在实际操作条件下稳定数天，并且避免了通常与 Pt 相关的结焦问题。因此，Pt/Cu SAA 为抗结焦 C-H 活化化学提供了一种新方法，并且具有额外的经济优势，即贵金属在原子极限处被稀释。
