Synthesis of TCO-free Dye-sensitized Solar Cells with Nanoporous Ti Electrodes Using RF Magnetron Sputtering Technology

Abstract

A new type of dye-sensitized solar cell (DSC) based on a porous type Ti electrode without using a transparent conductive oxide (TCO) layer is fabricated for low-cost high-efficient solar cell application. The TCO-free DSC is composed of a glass substrate/dye-sensitized <TEX>$TiO_2$</TEX> nanoparticle/porous Ti layer/electrolyte/Pt sputtered counter electrode. The porous Ti electrode (~350 nm thickness) with high conductivity can collect electrons from the <TEX>$TiO_2$</TEX> layer and allows the ionic diffusion of <TEX>$I^-/I_3{^-}$</TEX> through the hole. The vacuum annealing treatment is important with respect to the interfacial necking between the metal Ti and porous <TEX>$TiO_2$</TEX> layer. The efficiency of the prepared TCO-free DSC sample is about 3.5% (ff: 0.48, <TEX>$V_{oc}$</TEX>: 0.64V, <TEX>$J_{sc}$</TEX>: 11.14 mA/<TEX>$cm^2$</TEX>).