Zhang Xuge, Lin He, Zhang Jian, Qiu Yajun, Zhang Zedong, Xu Qi, Meng Ge, Yan Wensheng, Gu Lin, Zheng Lirong, Wang Dingsheng, Li Yadong
Department of Chemistry, Tsinghua University Beijing 100084 China
College of Chemistry and Materials Engineering, Wenzhou University Wenzhou Zhejiang 325035 China
Chem Sci. 2021 Oct 19;12(43):14599-14605. doi: 10.1039/d1sc04344g. eCollection 2021 Nov 10.
Single-atom (SA) catalysts have attracted broad attention due to their distinctive catalytic properties in diverse reactions. Increasing the unsaturated coordination sites of active centers is a valid and challenging approach to improve the performance of such catalysts. Herein, we report an oxide compounding strategy to decrease the N coordination number of a SA Cu catalyst by reducing the thickness of the N-doped carbon carrier with a lower density of N atoms. The SA Cu catalyst with a more unsaturated N coordination structure can achieve transfer hydrogenation of alkynes with good activity and selectivity, which is disabled over the common N coordinated SA Cu catalyst on pure CN. It is found that individual Cu centers coordinated by fewer N atoms can accelerate the hydrogen transfer from ammonia-borane and still leave proper adsorption sites for alkynes to realize the entire hydrogenation reaction. This work will open up new opportunities to modulate the unsaturated coordination structure of SA catalysts for creating better-performing heterogeneous catalysts.
单原子（SA）催化剂因其在各种反应中独特的催化性能而受到广泛关注。增加活性中心的不饱和配位点是提高此类催化剂性能的一种有效但具有挑战性的方法。在此，我们报道了一种氧化物复合策略，通过降低氮原子密度较低的氮掺杂碳载体的厚度来降低SA Cu催化剂的N配位数。具有更不饱和N配位结构的SA Cu催化剂能够实现炔烃的转移氢化反应，具有良好的活性和选择性，而在纯CN上的普通N配位SA Cu催化剂则无法实现。研究发现，由较少N原子配位的单个Cu中心可以加速氨硼烷的氢转移，同时仍为炔烃留下适当的吸附位点以实现整个氢化反应。这项工作将为调控SA催化剂的不饱和配位结构以制备性能更优的多相催化剂开辟新的机遇。
