摘要
The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic prop‐erties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indi‐cated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au：PVP.
聚(N-乙烯基-2-吡咯烷酮)稳定的金簇合物(Au:PVP)的质谱结果表明,来源于合成前驱体的Cl吸附质主要存在于Au_(34)和Au_(43)簇合物上.金簇合物上Cl吸附质的数量不影响其催化有氧苯甲醇氧化性能,表明Cl原子与Au簇合物间存在较弱的键合作用.相反,用Br替代Au_(34)和Au_(43)簇合物上Cl显著抑制了其催化活性,但对其电子结构没有任何影响.这表明,Br原子与金簇合物的键合较强,在空间上堵塞了活性位.因Br吸附质而导致活性显著下降表明,Au_(34)和Au_(43)簇合物对Au:PVP催化活性起主要贡献.
基金
supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB)
a Grant-in-Aid for Scientific Research (26248003, 15H01042) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan
