Double-layered TiO_2 photoelectrode with particulate structure prepared by one-step soaking method

Abstract

Nanostructured TiO2 films with double-layered structure are prepared by a facile one-step soaking method. We have investigated the morphology of nanostructured TiO2 films by the reaction time of the soaking method, which has an effect on the thickness and layered structure of the TiO2 films. The TiO2 films prepared by this method have a unique double-layered structure, which is composed of a dense TiO2 bottom layer and TiO2 particulates on the bottom layer. By manipulating the reaction time of the soaking method, control of TiO2 particulate formation on the surface of the dense TiO2 bottom layer is possible. The double-layered structure of nanostructured TiO2 films is effective for achieving sufficient adsorption of Sb2S3 sensitizer and light scattering effect of photoelectrodes for inorganic sensitized solar cells, which induces the enhancement of short circuit current of solar cell devices. Our solar cell device, using a double-layered TiO2 film with particulate structure as a photoelectrode, exhibited JSC, VOC, FF, and η values of 12.94 mA/cm2, 498 mV, 57.0%, and 3.67%, respectively.