The paper presents a dual-band plasmonic solar cell. The proposed unit structure gathers two layers, each layer consists of a silver nanoparticle deposited on a GaAs substrate and covered with an ITO layer, It reveals two discrete absorption bands in the infra-red part of the solar spectrum. Nanoparticle structures have been used for light-trapping to increase the absorption of plasmonic solar cells. By proper engineering of these structures, resonance frequencies and absorption coefficients can be controlled as it will be elucidated. The simulation results are achieved using CST Microwave Studio through the finite element method. The results indicate that this proposed dual-band plasmonic solar cell exhibits an absorption bandwidth, defined as the full width at half maximum, reaches 71 nm. Moreover, It can be noticed that by controlling the nanoparticle height above the GaAs substrate, the absorption peak can be increased to reach 0.77.

Results of the studies of optical properties of anti-reflective glasses with various texturization patterns, which were used as a coating for crystalline silicon solar cells, are presented. It was found that glass samples sorted by their optical transmittance demonstrated the same order as when sorted by their solar-cell short-circuit current enhancement parameter. The value of the latter depended on the parameters of texturization, such as the surface density of inclusions and their profile, and the depth of etching pits. A 2% relative increase of the solar cell efficiency was obtained for the best glass sample for null degree angle of incidence, proving enhanced light trapping properties of the studied glass.

In our studies the absorption, transmittance and reflectance spectra for periodic nanostructures with different parameters were calculated by the FDTD (Finite-Difference Time-Domain) method. It is shown that the proportion of reflected light in periodic structures is smaller than in case of thin films. The experimental results showed the light reflectance in the spectral range of 400–900 nm lower than 1% and it was significantly lower in comparison with surface texturing by pyramids or porous silicon.

Silicon nanowires on p-type Si substrate were formed by the Metal-Assisted Chemical Etching method (MacEtch). At solar cells with radial p-n junction formation the thermal diffusion of phosphorus has been used at 790°C. Such low temperature ensures the formation of an ultra-shallow p-n junction. Investigation of the photoelectrical properties of solar cells was carried out under light illumination with an intensity of 100 mW/cm². The obtained parameters of NWs' solar cell were I_sc = 22 mA/cm², U_oc = 0.62 V, FF = 0.51 for an overall efficiency η = 7%. The relatively low efficiency of obtained SiNWs solar cells is attributed to the excessive surface recombination at high surface areas of SiNWs and high series resistance.