A bifunctional TiO2 sol for convenient low-temperature fabrication of dye-sensitized solar cells

A TiO2 sol was synthesized and acted as a precursor of TiO2 nanoparticles in the application of low temperature dye-sensitized solar cells. It can also be used as an interparticle binder in the TiO2 mesoprous films. The overall efficiency of the cell with sol addition was found to be 13% higher than the one without it and achieved 4.41% under irradiation of 100 mW/cm2 AM1.5 sunlight. Electrochemical impedance spectra were applied to analyze the internal resistance changes of the cells with and without sol. Fine particles in the sol were proven to increase the electron life-time by improving the interconnectivity of the main particles.

► TiO2 sol as an interparticle binder and also a hydrothermal precursor.
► Mixure of TiO2 particles for photoanode fabrication at low temperature.
► Sol particle addition improves cell efficiency by enhancing particle connectivity.