Feng Quanchen, Zhao Shu, Xu Qi, Chen Wenxing, Tian Shubo, Wang Yu, Yan Wensheng, Luo Jun, Wang Dingsheng, Li Yadong
Department of Chemistry, Tsinghua University, Beijing, 100084, China.
Beijing Guyue New Materials Research Institute, Beijing University of Technology, Beijing, 100124, China.
Adv Mater. 2019 Sep;31(36):e1901024. doi: 10.1002/adma.201901024. Epub 2019 Jul 25.
Semihydrogenation of acetylene in the ethylene feed is a vital step for the industrial production of polyethylene. Despite their favorable reaction activity and ethylene selectivity, the Pd-based intermetallic compound and single-atom alloy catalysts still suffer from the limitation of atomic utilization derived from the partial exposure of active Pd atoms. Herein, a hard-template Lewis acid doping strategy is reported that can overcome the inefficient utilization of Pd atoms. In this strategy, N-coordinated isolated single-atomic Pd sites are fully embedded on the inner walls of mesoporous nitrogen-doped carbon foam nanospheres (ISA-Pd/MPNC). This synthetic strategy has been proved to be applicable to prepare other ISA-M/MPNC (M = Pt and Cu) materials. This ISA-Pd/MPNC catalyst with both high specific surface area (633.8 m g ) and remarkably thin pore wall (1-2 nm) exhibits higher activity than that of its nonmesoporous counterpart (ISA-Pd/non-MPNC) catalyst by a factor of 4. This work presents an efficient way to tailor and optimize the catalytic activity and selectivity by atomic-scale design and structural control.
乙炔在乙烯进料中的半加氢是聚乙烯工业生产的关键步骤。尽管基于钯的金属间化合物和单原子合金催化剂具有良好的反应活性和乙烯选择性，但由于活性钯原子的部分暴露，它们仍然存在原子利用率受限的问题。在此，报道了一种硬模板路易斯酸掺杂策略，该策略可以克服钯原子利用效率低下的问题。在该策略中，氮配位的孤立单原子钯位点完全嵌入介孔氮掺杂碳泡沫纳米球（ISA-Pd/MPNC）的内壁。这种合成策略已被证明适用于制备其他ISA-M/MPNC（M = Pt和Cu）材料。这种具有高比表面积（633.8 m²/g）和极薄孔壁（1-2 nm）的ISA-Pd/MPNC催化剂的活性比其非介孔对应物（ISA-Pd/non-MPNC）催化剂高4倍。这项工作提出了一种通过原子尺度设计和结构控制来定制和优化催化活性及选择性的有效方法。
