A simplified electrical model of the dye-sensitised photoelectrochemical cell

Abstract

This paper presents a steady-state electrical model of dye-sensitised solar cells with simplified boundary conditions. The codes are considerably concise and the sub-functions had confirmed good extensibility. This model is utilised to predict the current–voltage characteristics and the energy conversion efficiency based on various design and operating properties. The experimental data from the literature have been used to validate the theoretically fitted j−V characteristics of the presented model. Parametric simulations were conducted to analyse the effect of diffusion/drift, dye loading, and electrode thickness on dye-sensitised solar cell performance. Simulated results confirm that diffusion is the major driving force for electron and ion transport, while the drift of electrons is negligible. The model predicts optimal electrode thickness ranging between 10 and 15° μm which is consistent with the thickness (10 μm) used in general experimental studies published in the literature. Additionally, it is observed that there exists a logarithmic relation between the short-circuit current density and the amount of dye adsorption. This observation suggests that there exists a dominated recombination reaction which is responsible towards the high efficiency of DSCs.

Keywords:

• dye-sensitised solar cells
• drift diffusion
• theoretical modelling