Particle Size Effects of TiO₂Layers on the Solar Efficiency of Dye-Sensitized Solar Cells

Abstract

Large particle sizes having a strong light scattering lead to a significantly decreased surface area and small particle sizes having large surface area lack light-scattering effect. How to combine large and small particle sizes together is an interesting work for achieving higher solar efficiency. In this work, we investigate the solar performance influence of the dye-sensitized solar cells (DSSCs) by the multiple titanium oxide (TiO2) layers with different particle sizes. It was found that the optimal TiO2thickness depends on the particle sizes of TiO2layers for achieving the maximum efficiency. The solar efficiency of DSSCs prepared by triple TiO2layers with different particle sizes is higher than that by double TiO2layers for the same TiO2thickness. The choice of particle size in the bottom layer is more important than that in the top layer for achieving higher solar efficiency. The choice of the particle sizes in the middle layer depends on the particle sizes in the bottom and top layers. The mixing of the particle sizes in the middle layer is a good choice for achieving higher solar efficiency.

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

“…The results vary significantly, with optimum film thickness reported from anywhere between 9.5 µm and 20 µm [33][34][35][36][37][38][39] . Table 1 outlines the thicknesses of the TiO 2 printed layers and the efficiencies.…”

Performance Improvement of Flexible Dye-sensitized Solar Cells by Addition of Larger TiO2 Particle as Scattering Layer

“…It is known that smaller particles of TiO 2 film have large surface area and can absorb more dyes. Hence, they have low contact resistance and high photocurrent [2]. In addition, the increasing of large particle will be happened reabsorption in the small particle size TiO 2 .…”

“…Dye-sensitized solar cells (DSC) have attracted much attention from the scientific and commercial community due to the low production cost, good stability and high energy conversion efficiency 1,2 .…”

N719 and N3 dyes for quasi-solid state dye sensitized solar cells - A comparative study using polyacrylonitrile and CsI based electrolytes

“…The film surface is microstructurally homogenous. According to the manufacturer's specification the particle size of Degussa (Evonik) P90 powder is 14 nm, thus particle aggregates are seen in Figure 1 (Jeng et al, 2013) have also observed higher solar efficiencies when smaller particle sizes of TiO 2 are in the bottom layer (the 1 st layer) and larger particle sizes of TiO 2 are in the 2 nd layer.…”

“…It has to be noted that this meso-porous nature of the film is important for the efficient dye adsorption due to increased effective surface area of the TiO 2 photo-anode, which finally contributes to increase the short circuit photocurrent and enhance the efficiency. The larger particle size of TiO 2 layers in the 2 nd layer could enhance the back-scattering light effectively and increase the photocurrent (Jeng et al, 2013;Zhang and Jianga, 2015). The presence of the compact-spin coated layer in TiO 2 photo anode is important to scatter the light, to provide efficient electron percolation towards FTO from the porous TiO 2 layer and also to prevent internal short circuiting.…”