Facile Synthesis of Multi-Branched Gold Nanostructures through a TBAB-Assisted Route in Aqueous Solution and Their SERS Property

• Published in: Chinese journal of chemistry Vol. 29; no. 1; pp. 185 - 190
• Main Author: Wang, Luyan Wu, Xinzhou Pei, Meishan Wu, Zhiyan Li, Xiaonan Tao, Xutang
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 2011; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: gold; multi-branched; nanostructures; SERS; surface-enhanced Raman scattering; TBAB; tetrabutyl ammonium bromide; 水溶液; 简便合成; 纳米结构材料; 表面增强拉曼散射; 辅助线
• ISSN: 1001-604X; 1614-7065
• DOI: 10.1002/cjoc.201190049

Facile synthesis of multi-branched gold nanostructures by using the tetrabutyl ammonium bromide （TBAB） as a capping agent is described. The reaction is carried out in a one-step process at mild temperature. Gold nanostructures with more than six sharp branches ranging from 70 to 130 nm in length are synthesized in high yield. It is proposed that the relative weak adsorption capacity of TBAB leads to the incompletely covered gold surface and the growth of nanoparticles occurs on the uncovered gold surface, and therefore short branches appear consequently. Then positively charged TBAB layers on the gold surfaces prevent the branches from aggregating with each other which stimulates the branch growth. The prepared branched gold nanoparticles show efficient surface-enhanced Raman scattering （SERS） properties. Low temperature （4 ℃） is unfavorable to the formation of multi-branched gold nanostructures, and only thin small irregular plate-like nanoparticles are produced. The addition of SDS in TBAB aqueous solution results in forming SDS micelles at much lower concentration of SDS （0.4 mmol/L） as compared to that in pure water, and short branched gold nanoparticles are obtained in the SDS-TBAB system.