"Nanooptics and photonics"

The Impact of Exposure Time on the Optical Parameters of Silver Nanostructures
Bulavinets T.O.1, Yaremchuk I.Ya.1, Iluin O.V.1, Bobitski Ya.V.1,2
1 Department of Photonics, Lviv Polytechnic National University
12, S. Bandera Str., Lviv 79013, Ukraine 
E-mail: tetiana.o.bulavinets@lpnu.ua
2 College of natural sciences, Institute of Physics, University of Rzeszow 
Rzeszow, Poland.

The size and shape of the metal nanostructures are very important parameters because they fundamentally affect its physicochemical characteristics and unique plasmonic properties [1]. Our interest has been in the preparing of triangular silver nanoprisms with absorption peak at the desired wavelength. It is known that colloids color and optical characteristics of the nanotriangles can be tuned by irradiation with a precise wavelength [2]. The crucial parameters in this process are exposure time, wavelength and output power of radiation.
In this work the effect of wavelength and exposure time on the concentration and absorption peaks position of resulting nanostructures have been investigated. The formation of silver prismatic nanostructures was carried out by irradiating spherical nanoparticles with wavelength of 525 and 623 nm. It allows to obtain the silver nanoprisms with plasmon peaks in the visible and near infrared spectral region. It was found that exposure wavelength affects the absorption peak position and size of formed nanostructures. Thus, an absorption peak of about 890 nm was obtained by irradiation with green light and of 940 nm with red one. Increasing of exposure time leads to an increase in the nanotriangles concentration and therefore an increase in the peak absorption intensity.

1.	Sato-Berrú R. Y., Vázquez-Olmos A. R., Mejía-Uriarte E. V., Mata-Zamora M. E., Solís-Gómez A., Paraguay-Delgado F., Saniger J. M. Synthesis of Silver Colloids with a Homemade Light Source // Journal of Cluster Science. – 2018. – 29, N. 4, -P. 719-724.
2.	Xue C., Mirkin C. A. pH‐switchable silver nanoprism growth pathways // Angewandte Chemie International Edition. – 2007. – 46, N. 12. –P. 2036-2038.