Dye-Sensitized Solar Cells Based on Nanocrystalline TiO2 Films Surface Treated with Al3+ Ions: Photovoltage and Electron Transport Studies
Nanocryst. TiO2 films, surface modified with Al3+, were manufd. by depositing a TiO2 suspension contg. small amts. of Al nitrate or Al chloride onto conducting glass substrates, followed by drying, compression, and finally heating to 530°. Electrodes prepd. with TiO2 nanoparticles coated with <0.3% Al2O3 with respect to TiO2 improved the efficiency of the dye-sensitized solar cell. This amt. corresponds to less than a monolayer of Al2O3. Thus, the Al ions terminate the TiO2 surface rather than forming a distinct Al2O3 layer. The Al-ion surface treatment affects the solar cell in different ways: the potential of the conduction band is shifted, the electron lifetime is increased, and the electron transport is slower when Al ions are present between interconnected TiO2 particles.
Record created on 2015-07-06, modified on 2016-10-02