TY  - JOUR
A1  - Cui, Qianling
A1  - Yashchenok, Alexey
A1  - Li, Lidong
A1  - Moehwald, Helmuth
A1  - Bargheer, Matias
T1  - Mechanistic study on reduction reaction of nitro compounds catalyzed by gold nanoparticles using in situ SERS monitoring
JF  - Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science ; A, Physicochemical and engineering aspects
N2  - Surface-enhanced Raman scattering (SERS) spectroscopy has emerged in recent years as a promising and powerful technique to investigate the reaction mechanism of heterogeneous catalysis. In this work, the reduction reaction of 4-nitrothiophenol (4-NTP) to its corresponding amino derivate catalyzed by gold took place between the gold nanoshell and gold nanostar. Due to the strong binding of thiol group to the gold surface, the molecular configuration of 4-NTP was fixed with NO2 group towards outside. The direct contact of NO2 group with catalytic gold nanostars ensured the reduction reaction went smoothly, which was monitored by SERS spectroscopy. The NO2 vibration Raman band showed a unique blue-shift without any appearance of dimerization product, indicating this catalytic reaction might follow a monomolecular mechanistic pathway. (C) 2015 Elsevier B.V. All rights reserved.
KW  - Surface-enhanced Raman scattering
KW  - Heterogeneous catalysis
KW  - Gold nanoparticles
KW  - Reaction mechanism
KW  - Monomolecular reaction
Y1  - 2015
U6  - https://doi.org/10.1016/j.colsurfa.2015.01.075
SN  - 0927-7757
SN  - 1873-4359
VL  - 470
SP  - 108
EP  - 113
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Cui, Qianling
A1  - Xia, Bihua
A1  - Mitzscherling, Steffen
A1  - Masic, Admir
A1  - Li, Lidong
A1  - Bargheer, Matias
A1  - Moehwald, Helmuth
T1  - Preparation of gold nanostars and their study in selective catalytic reactions
JF  - Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science ; A, Physicochemical and engineering aspects
N2  - In this work, gold nanostars (AuNSs) with size around 90 nm were prepared through an easy one-step method. They show excellent catalytic activity and large surface-enhanced Raman scattering (SERS) activity at the same time. Surprisingly, they exhibited different catalytic performance on the reduction of aromatic nitro compounds with different substituents on the para position. To understand such a difference, the SERS spectra were recorded, showing that the molecular orientation of reactants on the gold surface were different. We anticipate that this research will help to understand the relationship of the molecular orientation with the catalytic activity of gold nanoparticles.
KW  - Nanoparticles
KW  - Gold
KW  - Catalytic reaction
KW  - Surface enhanced Raman scattering (SERS)
KW  - Molecular orientation
Y1  - 2015
U6  - https://doi.org/10.1016/j.colsurfa.2014.10.028
SN  - 0927-7757
SN  - 1873-4359
VL  - 465
SP  - 20
EP  - 25
PB  - Elsevier
CY  - Amsterdam
ER  -