来源 https://news.sciencenet.cn/htmlpaper/2022/3/202231314222631670864.shtm

华中师范大学郭彦炳团队报道了相邻sp杂化碳参与亚纳米团簇CuO/石墨烯界面上的分子氧活化。相关研究成果发表在2022年3月9日出版的《美国化学会杂志》。

O2的活化是氧化过程中的关键步骤。

该文中，采用sp杂化C≡C三键作为电子供体的概念，开发了高活性、稳定的分子氧活化催化剂。证明了亚纳米团簇CuO/石墨烯界面上邻近的sp杂交C和Cu位点是在桥接吸附模式下有效调节O2活化过程的关键结构。所制备的亚纳米簇CuO/石墨烯催化剂表现出最高的CO氧化活性，并且在133℃左右容易转化50%的CO，分别比CuO/石墨烯和CuO/活性炭催化剂低34℃和94℃。

原位漫反射红外傅里叶变换光谱和密度泛函理论计算结果表明，相邻的sp杂化C比sp2杂化C更有利于促进碳酸盐的快速解离，且无需克服任何能量壁垒。气态CO直接与活性分子氧反应，并倾向于通过E–R机制以相对较低的势垒（0.20 eV）进行。

该工作表明，sp杂交石墨烯基材料的C可以有效地提高O2活化效率，从而促进低温氧化过程。

附：英文原文

Title: Neighboring sp-Hybridized Carbon Participated Molecular Oxygen Activation on the Interface of Sub-nanocluster CuO/Graphdiyne

Author: Chuanqi Pan, Chenyang Wang, Xinya Zhao, Peiyan Xu, Feihong Mao, Ji Yang, Yuhua Zhu, Ruohan Yu, Shiyi Xiao, Yarong Fang, Hongtao Deng, Zhu Luo, Jinsong Wu, Junbo Li, Shoujie Liu, Shengqiang Xiao, Lizhi Zhang, Yanbing Guo

Issue&Volume: March 9, 2022

Abstract: Activation of O2 is a crucial step in oxidation processes. Here, the concept of sp-hybridized C≡C triple bonds as an electron donor is adopted to develop highly active and stable catalysts for molecular oxygen activation. We demonstrate that the neighboring sp-hybridized C and Cu sites on the interface of the sub-nanocluster CuO/graphdiyne are the key structures to effectively modulate the O2 activation process in the bridging adsorption mode. The as-prepared sub-nanocluster CuO/graphdiyne catalyst exhibited the highest CO oxidation activity and readily converted 50% CO at around 133 °C, which is 34 and 94 °C lower than that for CuO/graphene and CuO/active carbon catalysts, respectively. In situ diffused reflectance infrared Fourier transform spectroscopy and density functional theory calculation results proved that the neighboring sp-hybridized C is more favorable to promote the rapid dissociation of carbonate than sp2-hybridized C without overcoming any energy barrier. The gaseous CO directly reacts with the active molecular oxygen and tends to proceed through the E–R mechanism with a relatively low energy barrier (0.20 eV). This work revealed that sp-hybridized C of graphdiyne-based materials could effectively improve the O2 activation efficiency, which could facilitate the low-temperature oxidation processes.

DOI: 10.1021/jacs.1c12772

Source: https://pubs.acs.org/doi/10.1021/jacs.1c12772

 

 

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