title: White-light induced grafting of 3-MPA on the Si(111)-H surface for catalyzing Au nanoparticles' in situ growth.
abstract: A novel, mild and effective method was designed for grafting of high-quality organic monolayers on a silicon surface to catalyze nanoparticles' growth. By using a white-light source, 3-mercaptopropionic acid (3-MPA) molecules were attached to hydrogen-terminated Si(111) surfaces at room temperature. The attached monolayers were characterized using X-ray photoelectron spectroscopy to provide detailed information. The in situ growth of Au nanoparticles (AuNPs) with dimensions below 20 nm was catalyzed on a silicon surface with highly uniform and compact structure morphology. The AuNPs can grow selectively in a certain region on a patterned Si-Si3N4 chip. p-Nitrothiophenol (p-NTP) was used as the probe to evaluate the SERS enhancement of the highly uniform and compact AuNP-Si substrate. In order to better understand the white light initiation of the addition reaction of 3-MPA on the Si(111)-H surface, the mechanism was elucidated by density functional theoretical (DFT) calculations, which indicated that the formation of the Si-O bond occurred at the PEC of the first singlet excited state (S1) with a very low activation barrier about 30% of the ground state (S0) value.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China. dywu@xmu.edu.cn fzyang@xmu.edu.cn.
authors.forename: Li-Kun
authors.initials: LK
authors.lastname: Yang
authors.forename: Ya-Qiong
authors.initials: YQ
authors.lastname: Su
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Wu
authors.forename: Da-Xiao
authors.initials: DX
authors.lastname: Zhang
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Chen
authors.forename: Fang-Zu
authors.initials: FZ
authors.lastname: Yang
authors.forename: De-Yin
authors.initials: DY
authors.lastname: Wu
authors.forename: Zhong-Qun
authors.initials: ZQ
authors.lastname: Tian