Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
Department of Materials Science and Engineering, Lehigh University, 5 East Packer Avenue, Bethlehem, PA 18015, USA.
Science. 2017 Mar 31;355(6332):1399-1403. doi: 10.1126/science.aal3439.
There remains considerable debate over the active form of gold under operating conditions of a recently validated gold catalyst for acetylene hydrochlorination. We have performed an in situ x-ray absorption fine structure study of gold/carbon (Au/C) catalysts under acetylene hydrochlorination reaction conditions and show that highly active catalysts comprise single-site cationic Au entities whose activity correlates with the ratio of Au(I):Au(III) present. We demonstrate that these Au/C catalysts are supported analogs of single-site homogeneous Au catalysts and propose a mechanism, supported by computational modeling, based on a redox couple of Au(I)-Au(III) species.
在最近经过验证的乙炔氯化金催化剂的操作条件下，对于金的活性形式仍存在相当大的争议。我们在乙炔氯化反应条件下对金/碳（Au/C）催化剂进行了原位 X 射线吸收精细结构研究，结果表明，高活性催化剂包含单活性位阳离子 Au 实体，其活性与存在的 Au(I):Au(III)比值相关。我们证明这些 Au/C 催化剂是单活性位均相 Au 催化剂的负载类似物，并提出了一种基于 Au(I)-Au(III)物种氧化还原对的机制，该机制得到了计算模拟的支持。
