The significance of bromide in the Brust–Schiffrin synthesis of thiol protected gold nanoparticles

DOI: 10.1039/C7SC03266H

Authors: S. G. Booth (University of Manchester) , A. Uehara (Kyoto University) , Sin-Yuen Chang (Diamond Light Source) , C. La Fontaine (Synchrotron Soleil) , T. Fujii (Osaka University) , Y. Okamoto (Japan Atomic Energy Agency) , T. Imai (Ryukoku University) , S. L. M. Schroeder (Diamond Light Source; University of Leeds) , R. A. W. Dryfe (University of Manchester)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Chemical Science , VOL 8 , PAGES 7954 - 7962

State: Published (Approved)
Published: September 2017

Abstract: The mechanism of the two-phase Brust–Schiffrin synthesis of alkane thiol protected metal nanoparticles is known to be highly sensitive to the precursor species and reactant conditions. In this work X-ray absorption spectroscopy is used in conjunction with liquid/liquid electrochemistry to highlight the significance of Br− in the reaction mechanism. The species [AuBr4]− is shown to be a preferable precursor in the Brust–Schiffrin method as it is more resistant to the formation of Au(I) thiolate species than [AuCl4]−. Previous literature has demonstrated that avoidance of the Au(I) thiolate is critical to achieving a good yield of nanoparticles, as [Au(I)X2]− species are more readily reduced by NaBH4. We propose that the observed behavior of [AuBr4]− species described herein explains the discrepancies in reported behavior present in the literature to date. This new mechanistic understanding should enable nanoparticle synthesis with a higher yield and reduce particle size polydispersity.

Subject Areas: Chemistry, Materials

Facility: SOLEIL

Added On: 07/12/2017 13:59

Documents:
C7SC03266H.pdf

Discipline Tags:

Physical Chemistry Chemistry Materials Science Nanoscience/Nanotechnology

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