Shang Shu, Li Lei, Wang Hui, Zhang Xiaodong, Xie Yi
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China.
Institute of Energy, Hefei Comprehensive National Science Center, Hefei, Anhui 230031, China.
Nano Lett. 2023 Aug 23;23(16):7650-7657. doi: 10.1021/acs.nanolett.3c02279. Epub 2023 Aug 3.
The chemical fixation of CO as a C1 feedstock is considered one of the most promising ways to obtain long-chain chemicals, but its efficiency was limited by the ineffective activation of CO. Herein, we propose a grain boundary engineering strategy to construct polarized active pairs with electron poor-rich character for effective CO activation. By taking CeO as a model system, we illustrate that the polarized "Ce-Ce-Ce" pairs at the grain boundary can simultaneously accept and donate electrons to coordinate with O and C, respectively, in CO. By the combination of synchrotron radiation in situ technique and density functional theory calculations, the mechanism of the catalytic reaction has been systematically investigated. As a result, the CeO nanosheets with a rich grain boundary show a high DMC yield of 60.3 mmol/g with 100% atomic economy. This study provides a practical way for the chemical fixation of CO to high-value-added chemicals via grain boundary engineering.
将CO作为C1原料进行化学固定被认为是获得长链化学品最有前景的方法之一，但其效率受到CO活化效果不佳的限制。在此，我们提出一种晶界工程策略，构建具有缺电子-富电子特性的极化活性对以实现有效的CO活化。以CeO作为模型体系，我们阐明了晶界处极化的“Ce-Ce-Ce”对可同时接受和提供电子，分别与CO中的O和C配位。通过同步辐射原位技术与密度泛函理论计算相结合，系统地研究了催化反应机理。结果，具有丰富晶界的CeO纳米片显示出60.3 mmol/g的高碳酸二甲酯产率以及100%的原子经济性。本研究为通过晶界工程将CO化学固定为高附加值化学品提供了一条切实可行的途径。
