title: Solvent-induced desorption of alkanethiol ligands from Au nanoparticles.
abstract: Removing surfactants from a colloidal metal nanoparticle surface is necessary for their realistic applications, and how they could be stripped is a subject of active investigation. Here, we report a solvent-induced desorption of dodecanethiol ligands from the gold nanoparticle surface, and traced this desorption process using a combination of in situ X-ray absorption fine structure (XAFS) and Raman spectroscopic techniques. In situ analysis results reveal that the solvent exchange of ethanol with tetrahydrofuran (THF) can effectively remove dodecanethiol ligands while keeping the particle morphology unchanged. Upon increasing the THF/ethanol ratio from 0 : 1 to 5 : 1, the surface coverage of thiol on the Au surface is reduced from 0.47 to 0.07, suggesting the depletion of ligands first from the nanoparticle facet sites, then from the edge sites, while the ligands at the corner sites are intact. This work enriches our knowledge on surfactant removal and may pave the way towards preparing surface-clean nanoparticles for practical applications.
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China. yaot@ustc.edu.cn hanyanjy@ustc.edu.cn.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Huang
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Hao
authors.initials: H
authors.lastname: Cheng
authors.forename: Tao
authors.initials: T
authors.lastname: Yao
authors.forename: Lina
authors.initials: L
authors.lastname: Yang
authors.forename: Jie
authors.initials: J
authors.lastname: Bao
authors.forename: Ting
authors.initials: T
authors.lastname: Huang
authors.forename: Zhihu
authors.initials: Z
authors.lastname: Sun
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.forename: Shiqiang
authors.initials: S
authors.lastname: Wei