A simulation study on the effect of size gold nanoparticles on broadband light absorption in dye-sensitised solar cells

Abstract

Plasmon-assisted energy conversion in dye-sensitised solar cells (DSSCs) has been achieved by applying gold (Au) nanoparticles (NPs) inside Titania (TiO2) photoanodes. Gold nanoparticles (GNPs) were introduced into DSSCs to further enhance their power conversion efficiency (PCE). In this research work, an effort has been made to enhance the optical absorption and improve the performance of DSSCs. By utilising finite-difference time-domain (FDTD) software, GNPs with radii of 15, 25, 35, 45, 55, 65, 75 and 85 nm were produced and introduced into the TiO2 photoanode. The optimum radius for the optical absorption enhancement was found to be 85 nm because the effect of plasmon coupling is more significant for metal nanoparticle sizes > 60 nm. The effect of various sizes of GNPs on light scattering has also been presented in this study. Moreover, the investigation has focused on the role of incident angle of light source on the absorption in TiO2 films. It was found that the optimum incident angle for the enhancement of broadband optical absorption in the wavelength range of 450–800 nm is 70°.