Nanostructured surfaces

Influence of surface plasmon resonance on the efficiency of organic solar cells
Biliuk A.A. Semchuk O.Yu., Havryliuk O.O.
Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine 17 General Naumov Str. Kyiv-03164, Ukraine. 
E-mail: philosoph.tb@gmail.com

Over the last decade, there has been an increased interest in the field of organic solar cells (OSCs) because of their future potential as an inexpensive technology for electricity production.  OSCs are the potential substitute for the traditional Si solar cells due to its low manufacturing cost, light weight and device flexibility.
Therefore, in our work we will use PEDOT: PSS as one of the elements of the solar cell. Our studies will demonstrate the effect on the solar cell depending on the position, size and shape of the metal particles added to the organic conductor layer. 
The optical spectra of metal nanoparticles are characterized by the presence in the range of visible light of a pronounced resonance band, which is called the surface plasmon resonance band (LSPR). The location of the LSPR band is significantly influenced by the shape of the nanoparticles and the dielectric properties of the environment. In OSC, metal nanoparticles can primarily act as additional scattering elements for the long-wavelength component of sunlight illuminating the solar cell (SC). In particular, in the presence of a reflective rear metal contact, the light reflected in the direction of the SC surface will be partially redirected by the metal nanoparticles back into the semiconductor. As a collective phenomenon, LSPR can be described using kinetic approaches, ie using the Boltzmann kinetic equation for the conduction electrons of metal nanoparticles. With its help, the optical absorption of light by small metal particles whose dimensions are much smaller than the wavelength of light (laser radiation) was studied. 
In this paper, the LSPR theory is based on the kinetic equation for the conduction electrons of nanoparticles. The LSPR frequency is found for metal nanoparticles of arbitrary shape in the dielectric matrix. The developed theory is used to calculate the optical conductivity tensor for spheroidal metal nanoparticles. It is shown that the effect of nanoparticle asymmetry on the ratio of the components of the optical conductivity tensor differs not only quantitatively but also qualitatively in high-frequency and low-frequency surface scattering. It is found that in metal nanoparticles in the dielectric matrix, under conditions of surface plasmon resonance, the full width of the LSPR line in a spherical metal nanoparticle depends on both the radius of the particle R and the wavelength of solar radiation exciting this LSPR, which consists of two describe the smooth and oscillating parts of the width of the LSPR line. By controlling the size, shape of the nanosized particle material and using the PEDOT as its environment, it is possible to control the conditions of resonance in the entire visible and near infrared range, due to which we will increase the ability of the solar cell to convert sunlight into energy.
In further studies, it is planned to calculate the gain of such structures with and without metal nanoparticles. And also to compare the characteristics of these solar cells with existing analogues.