A facile template-free route for synthesis of anatase TiO2 hollow spheres for dye-sensitized solar cells

TiO2 hollow spheres with outer diameter of 1.0-2.5 mu m and shell thickness of 200 nm are successfully prepared via a facile hydrothermal method without use of any template agent. The as-prepared TiO2 hollow spheres are crystalline of the anatase phase, and possess a specific surface area of 48 m(2) g(-1). A high power conversion efficiency of 7.68% is achieved for dye-sensitized solar cell (DSSC) based on TiO2 hollow sphere photoanode, representing a 16% efficiency boost over that of 6.65% achieved with the P25 based DSSC. Based on the optical investigation and electrochemical impedance measurement, the improved performance can be attributed to the enhanced light-scattering and the reduced interface recombination. Crown Copyright (C) 2014 Published by Elsevier Ltd. All rights reserved.