Enhanced Absorption Performance of Dye-Sensitized Solar Cell with Composite Materials and Bilayer Structure of Nanorods and Nanospheres

Abstract

The concept of localized surface plasmon resonance has been applied to increase the absorption efficiency of dye-sensitive solar cells (DSSCs) by using various photoanode structures. A three-dimensional model for a photoanode of the DSSC based on composite materials was developed using COMSOL Multiphysics. Spherical-, rod- and triangular-shaped aluminum nanoparticles were employed in the core of SiO2 to examine the influence of morphology on the performance of DSSCs in the 350–750 nm wavelength range. The UV-Vis absorption results indicated that aluminum nanoparticles with spherical, rod and triangle morphologies had 39.5%, 36.1% and 34.6% greater absorption capability than aluminum-free nanoparticles. In addition, we investigated the effect of plasmonic absorption in DSSCs for photoanodes made of TiO2, SiO2 and bilayer TiO2/SiO2 with and without covering aluminum nanoparticles. The TiO2 and SiO2 nanoparticles had fixed diameters of 90 nm each. The UV-Vis absorption and Tauc curves indicated that the TiO2/SiO2 bilayer structure (with and without aluminum nanoparticles) had greater absorption and lower bandgap energies than individual TiO2 and SiO2 nanoparticles. Furthermore, bilayer photoanode nanostructures were investigated based on nanospheres and nanorods for core–shell Al@SiO2 nanoparticles. The results indicated that a photoanode with nanorod/nanosphere structure had a 12% better absorption capability than a nanosphere/nanorod configuration. This improvement in absorption is attributed to the high surface area, which boosts dye loading capacity and long-term light capture, resulting in greater interaction between the dye and the photon. Our study develops core–shell nanoparticles with optimized shape and materials for bilayer photoanode structures in photovoltaic technology.