jz300960b Xie Presentation


Published on

This presentation has been moved. To view this presentation, please visit http://pubs.acs.org/iapps/liveslides/pages/index.htm?mscNo=jz300960b

Fast Synthesis of Thiolated Au25 Nanoclusters via ProtectionDeprotection Method

Published in: Education
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

jz300960b Xie Presentation

  1. 1. Fast Synthesis of Thiolated Au25 Nanoclusters via Protection-Deprotection MethodXun Yuan, Yong Yu, Qiaofeng Yao, Qingbo Zhang, and Jianping Xie* Department of Chemical and BiomolecularEngineering, National University of Singapore, 4 Engineering Drive 4, 117576, Singapore*Email: chexiej@nus.edu.sg; Tel: +65 6516 1067J. Phys. Chem. Lett. 2012, 3, 2310 -2314 1
  2. 2. Motivations for This Project • The design of a fast and efficient synthesis of atomically precise nanoclusters (NCs) is pivotal in realizing their practical applications in areas such as biomedical and catalysis. - Currently, there are two main synthetic strategies for the synthesis of atomically precise Au NCs. 1. Thiolate-protected Au NCs based on the unique thiolate-Au interactions. 2. Template-directed Au NCs based on the steric hindrance provided by the template molecules. - A paradigm shift synthetic strategy (protection-deprotection method) was developed in this study. 1. Inspired from the protection-deprotection strategy in organic synthesis to achieve chemoselectivity. 2. Integrated two main synthesis strategies into one protocol: unique thiolate-Au interactions + steric hindrance of the templates. 3. Faster and more efficient. Proprietary and Confidential 2 American Chemical Society
  3. 3. Protection-Deprotection Method HAuCl4 Cysteine Water (2) Reduction & (1) Protection Phase transfer Cys-AuI Complexes CTAB Toluene & NaBH4 S 7 min CTAB-protected Cys-AuI Complexes CTAB-protected Cys-Au25 NCs in Toluene Cys-AuI Complexes 2 min (3) Deprotection CTA+ Cys-Au25 NCs in Water • Protection: a removable CTAB layer was introduced to protect the thiolate- AuI complexes during the NaBH4 reduction, leading to the direct formation of thiolated Au25 NCs. • Deprotection: the CTAB layer was removed by the addition of a hydrophobic anionic surfactant, shuttling back the NCs to the aqueous phase.Proprietary and Confidential 3American Chemical Society
  4. 4. High Purity of Thiolated Au25 NCsin Our Crude Product • Cys: cysteineProprietary and Confidential 4American Chemical Society
  5. 5. Extendable to the Synthesis of Au25 NCs Protected by Other Thiolate Ligands • MPA: 3-mercaptopropionic acidProprietary and Confidential 5American Chemical Society
  6. 6. Conclusions Protection-Deprotection Method • Integrated the unique thiolate-Au interactions and the steric hindrance of a removable template (CTAB) into one synthetic protocol. • A simple and fast (< 10 min) synthesis method for high purity thiolated Au25 NCs. • A paradigm shift synthetic strategy which could be applied to synthesize other atomically precise metal NCs. Please visit our website for more information Jianping Xie Group @ NUS: http://cheed.nus.edu.sg/~chexiej/index.htmlProprietary and Confidential 6American Chemical Society