Preparation of Smooth Surface TiO₂ Photoanode for High Energy Conversion Efficiency in Dye‐Sensitized Solar Cells

Abstract

Dye‐sensitized solar cells (DSSCs) based on a TiO 2 photoanode have been considered as an alternative source in the field of renewable energy resources. In DSSCs, photoanode plays a key role to achieve excellent photo‐to‐electric conversion efficiency. The surface morphology, surface area, TiO 2 crystal phase, and the dispersion of TiO 2 nanoparticles are the most important factors influencing the properties of a photoanode. The smooth TiO 2 surface morphology of the photoanode indicates closely packed arrangement of TiO 2 particles which enhance the light harvesting efficiency of the cell. In this paper, a smooth TiO 2 photoanode has been successfully prepared using a well‐dispersed anatase TiO 2 nanosol via a simple hydrothermal process. The above TiO 2 photoanode was then compared with the photoanode made from commercial TiO 2 nanoparticle pastes. The morphological and structural analyses of both the aforementioned photoanodes were comprehensively characterized by scanning electron microscopy and X‐ray diffraction analysis. The DSSC fabricated by using a‐TiO 2 nanosol‐based photoelectrode exhibited an overall light conversion efficiency of 7.20% and a short‐circuit current density of 13.34 mA cm −2 , which was significantly higher than those of the DSSCs with the TiO 2 nanoparticles‐based electrodes.