TY  - GEN
A1  - Liebig, Ferenc
A1  - Henning, Ricky
A1  - Sarhan, Radwan Mohamed
A1  - Prietzel, Claudia Christina
A1  - Schmitt, Clemens Nikolaus Zeno
A1  - Bargheer, Matias
A1  - Koetz, Joachim
T1  - A simple one-step procedure to synthesise gold nanostars in concentrated aqueous surfactant solutions
T2  - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe
N2  - Due to the enhanced electromagnetic field at the tips of metal nanoparticles, the spiked structure of gold nanostars (AuNSs) is promising for surface-enhanced Raman scattering (SERS). Therefore, the challenge is the synthesis of well designed particles with sharp tips. The influence of different surfactants, i.e., dioctyl sodium sulfosuccinate (AOT), sodium dodecyl sulfate (SDS), and benzylhexadecyldimethylammonium chloride (BDAC), as well as the combination of surfactant mixtures on the formation of nanostars in the presence of Ag⁺ ions and ascorbic acid was investigated. By varying the amount of BDAC in mixed micelles the core/spike-shell morphology of the resulting AuNSs can be tuned from small cores to large ones with sharp and large spikes. The concomitant red-shift in the absorption toward the NIR region without losing the SERS enhancement enables their use for biological applications and for time-resolved spectroscopic studies of chemical reactions, which require a permanent supply with a fresh and homogeneous solution. HRTEM micrographs and energy-dispersive X-ray (EDX) experiments allow us to verify the mechanism of nanostar formation according to the silver underpotential deposition on the spike surface in combination with micelle adsorption.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 769 
KW  - optical-properties
KW  - nanoparticles
KW  - sers
KW  - ultrafast
KW  - size
KW  - nanotriangles
KW  - nanoflowers
KW  - wavelength
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-438743
SN  - 1866-8372
IS  - 769
SP  - 23633
EP  - 23641
ER  - 
TY  - GEN
A1  - Raju, Rajarshi Roy
A1  - Liebig, Ferenc
A1  - Hess, Andreas
A1  - Schlaad, Helmut
A1  - Koetz, Joachim
T1  - Temperature-triggered reversible breakdown of polymer-stabilized olive
BT  - silicone oil Janus emulsions
T2  - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe
N2  - A one-step moderate energy vibrational emulsification method was successfully employed to produce thermo-responsive olive/silicone-based Janus emulsions stabilized by poly(N,N-diethylacrylamide) carrying 0.7 mol% oleoyl side chains. Completely engulfed emulsion droplets remained stable at room temperature and could be destabilized on demand upon heating to the transition temperature of the polymeric stabilizer. Time-dependent light micrographs demonstrate the temperature-induced breakdown of the Janus droplets, which opens new aspects of application, for instance in biocatalysis.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 751 
KW  - microgels
KW  - step
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436461
SN  - 1866-8372
IS  - 751
SP  - 19271
EP  - 19277
ER  -