Single-Atom AuI-N3 Site for Acetylene Hydrochlorination Reaction
Single-Atom AuI-N3 Site for Acetylene Hydrochlorination Reaction
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用于乙炔氢氯化反应的单原子 Au-I-N-3 位点
DOI：
10.1021/acscatal.9b05212
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发表时间：
2020-02-07
期刊：
影响因子：
12.9
通讯作者：
Li, Yadong
中科院分区：
文献类型：
--
作者：
Chen, Zheng;Chen, Yinjuan;Li, Yadong
金催化乙炔氢氯化反应是聚氯乙烯工业中生产氯乙烯单体的重要工艺。传统的碳载AuCl3催化剂在反应过程中容易被乙炔还原而失去活性。在这里，我们提出了通过分散在 g-C3N4 (Au-1/g-C3N4) 上的单个金原子构建 Au-I-N-3 活性位点，这对乙炔氢氯化反应表现出强大的催化性能。 Au 物质具有 Au' 氧化态，并且与三均三嗪重复单元的三个氮原子配位，这与密度泛函理论 (DFT) 建模和 XAFS 测量一致。通过DFT研究，我们证明Au-I-N-3位点在初始反应中更倾向于与HCl配位，而不是与C2H2配位。 Au-I-N-3位点不易被还原成Au-0氧化态，从而保持其作为稳定催化活性位点的活性。具有氮配位环境和相应电子态的单原子位Au催化剂为乙炔氢氯化反应提供了有效的途径。
The gold-catalyzed acetylene hydrochlorination reaction is an important process to produce vinyl chloride monomer in the polyvinyl chloride industry. The traditional catalyst of carbon-supported AuCl3 is inclined to be reduced by acetylene and lose its activity during the reaction process. Here, we presented the construction of Au-I-N-3 active sites through single gold atom dispersed on g-C3N4 (Au-1/g-C3N4), which shows robust catalytic performance toward acetylene hydrochlorination. The Au species is shown to have Au' oxidation state, and it is coordinated with three nitrogen atoms of tri-s-triazine repeating units, which is consistent with density functional theory (DFT) modeling and XAFS measurements. Through DFT study, we demonstrate that the Au-I-N-3 sites tend to coordinate with HCl than C2H2 in the initial reaction. The Au-I-N-3 sites cannot be reduced into Au-0 oxidation state easily and thus maintain their activity as stable catalytic active sites. The single-atom-site Au catalyst with nitrogen coordination environment and corresponding electronic state provides an efficient pathway for acetylene hydrochlorination reaction.