The effect of surface plasmon resonance on the photovoltaic properties of CdS quantum dot sensitized solar cells

Use of surface plasmon resonance effect of the Ag nanoparticles (Ag NPs) towards the photophysical properties of CdS quantum dot sensitized TiO₂ based solar cells (QDSSCs) was investigated under the illumination of 100 mW cm^-2 (AM 1.5). Depositions of CdS on TiO₂ electrodes were carried out by successive ionic layer adsorption and reaction (SILAR) method with optimized ten cycles. Current voltage characteristics of QDSSCs fabricated with optimum amount of Ag NPs (0.2 % w/v) in TiO₂ showed ~ 26% increment in the power conversion efficiency from 1.09 to 1.37%. Surface morphological studies of photoanodes were carried out with scanning electron microscopy, high-resolution transition electron microscopy and energy dispersive X-ray measurements (EDX). The existence of spherical shape Ag nanoparticles in TiO₂ with an average particle size of 35 nm was confirmed by EDX analysis. The estimated average size of the TiO₂ and CdS particles appears to be around 40 nm and 4.2 nm respectively.