Improved Energy Conversion Efficiency of Dye-sensitized Solar Cells Fabricated using Open-ended TiO2 Nanotube Arrays with Scattering Layer

We prepared dye-sensitized solar cells (DSSCs) with enhanced energy conversion efficiency using open-ended TiO2 nanotube arrays with a TiO2 scattering layer. As compared to closed-ended TiO2 nanotube arrays, the energy conversion efficiency of the open-ended TiO2 nanotube arrays was increased from 5.63% to 5.92%, which is an enhancement of 5.15%. With the TiO2 scattering layer, the energy conversion efficiency was increased from 5.92% to 6.53%, which is an enhancement of 10.30%. After treating the open-ended TiO2 nanotube arrays with TiCl4, the energy conversion efficiency was increased from 6.53% to 6.89%, a 5.51% enhancement, which is attributed to improved light harvesting and increased dye adsorption.