Abstracts Book - IMRC 2018

• SA6-O021
SiO2, MnO2, TiO2 or ZrO2- PROTECTED GOLD AND SILVERS
NANOPARTICLES: SYNTHESIS AND APPLICATION AS
NANORESONATORS FOR RAMAN ANALYSIS OF SURFACES
Jan Krajczewski 1
1 University of Warsaw, Faculty of Chemistry, Poland.
In this contribution we present new types of nanoresonators: gold and silver
nanoparticles coated by nanometric, protective layer of SiO2, MnO2, TiO2 and
ZrO2. Various nanoparticles were prepared by different methods. Spherical,
hollow spherical and branched nanoparticles were prepared by chemical
methods. Gold bipyramids were synthesized by ,,seed mediated growth method
using CTAB as stabilizing agent. Silver nanodecahedrons were prepared by
photochemical method. Oxides layer were prepared by chemical methods. For
example silica layer is formed in process of tetraethyl orthosilicate
decomposition in presence of ammonia as catalyst. Nanometric layer of oxide
do not dump optical properties of nanoparticles. However, presence of oxide
layer significantly increase its durability in adverse environmental conditions like
very high or low pH. Structural and optical properties of obtained
nanocomposite were carefully examined. Comparison of oxide layer durability
were carried out. We present application of obtained nanoresonators as optical
nanoresonators of SHINERS measurements. Gold and silver nanoparticles act as
electromagnetic nanoresonators, significantly enhancing electric field of the
incident electromagnetic radiation and hence leading to large increase of the
Raman signal the studied surface. The inert shell separates metal cores direct
contact with probed molecules and keeps them agglomeration. Therefore, such
systems might find more analytical applications, also for living cells.
Acknowledgment:
This work was financed the funds of the National Science Centre (Poland)
allocated on the basis of the decision number DEC-2013/11/B/ST5/02224.
Keywords: nanoparticles, SERS, SHINERS
Presenting authors email: jkrajczewski@chem.uw.edu.pl