The better photoelectric performance of thin-film TiO2/c-Si heterojunction solar cells based on surface plasmon resonance

Abstract

In this work, the absorption of solar energy of thin-film c-silicon (silicon is 1 μm) heterojunction solar cells (SSCs) with the combination of Ag nanoparticles (NPs) and TiO2 inverted triangular prism (IP) is enhanced significantly. The top TiO2 IP increases the short wavelengths absorption by coupling the incident light into photonic modes in the active layer. The bottom Ag NPs primarily enhances the absorption of longer wavelengths by coupling incident light into surface plasmon resonance (SPR). Thus, the average solar energy absorption is 91.40% under AM 1.5 solar spectrum. The geometries of the Ag NPs and TiO2 IP are optimized that based on the maximum values of the Jsc. The maximum Jsc is 32.81 mA/cm2. The highest PCE of 14.16% is obtained in a solar cell containing the integrated structure of Ag NPs and TiO2 IP. Besides, to further explain the mechanism of solar energy absorption by SSCs, electric field intensity distribution profiles for different structures of SSCs at different wavelengths are analyzed in both TM direction (polarization along x-direction) and TE polarizations (polarization along y-direction).

Keywords

• Thin-film c-silicon heterojunction solar cells
• Solar energy absorption
• TiO2 inverted triangular prism
• Surface plasmon resonance
• Finite-difference time-domain