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  - 
TY  - JOUR
A1  - Sarhan, Radwan Mohamed
A1  - Koopman, Wouter-Willem Adriaan
A1  - Pudell, Jan-Etienne
A1  - Stete, Felix
A1  - Rössle, Matthias
A1  - Herzog, Marc
A1  - Schmitt, Clemens Nikolaus Zeno
A1  - Liebig, Ferenc
A1  - Koetz, Joachim
A1  - Bargheer, Matias
T1  - Scaling up nanoplasmon catalysis
BT  - the role of heat dissipation
JF  - The journal of physical chemistry : C, Nanomaterials and interfaces
N2  - Nanoscale heating by optical excitation of plasmonic nanoparticles offers a new perspective of controlling chemical reactions, where heat is not spatially uniform as in conventional macroscopic heating but strong temperature gradients exist around microscopic hot spots. In nanoplasmonics, metal particles act as a nanosource of light, heat, and energetic electrons driven by resonant excitation of their localized surface plasmon resonance. As an example of the coupling reaction of 4-nitrothiophenol into 4,4′-dimercaptoazobenzene, we show that besides the nanoscopic heat distribution at hot spots, the microscopic distribution of heat dictated by the spot size of the light focus also plays a crucial role in the design of plasmonic nanoreactors. Small sizes of laser spots enable high intensities to drive plasmon-assisted catalysis. This facilitates the observation of such reactions by surface-enhanced Raman scattering, but it challenges attempts to scale nanoplasmonic chemistry up to large areas, where the excess heat must be dissipated by one-dimensional heat transport.
KW  - Gold
KW  - Raman spectroscopy
KW  - Silicon
KW  - Irradiation
KW  - Lasers
Y1  - 2019
U6  - https://doi.org/10.1021/acs.jpcc.8b12574
SN  - 1932-7447
VL  - 123
IS  - 14
SP  - 9352
EP  - 9357
PB  - American Chemical Society
CY  - Washington
ER  -