Low Temperature Preparation and Absorption Spectra of Nanocrystalline Pb1-xLaxTiO3 Thin Film on ITO Conducting Glass Substrate

Nanocrystalline precursors of Pb_1-xLa_xTiO₃ (PLT, x=0.06, 0.10, 0.14 and 0.20) thin film were prepared on ordinary ITO conducting glass substrate using sol-gel and pulling method. After the precursors were calcined at low temperature of 185-400℃ in air atmosphere for 1-6 h, the resulted nanocrystalline thin film was characterized by XRD, SEM and AFM. The spectra show that the solid state chemical reaction and the grain size of the nanocrystalline thin film relate not only to the precursor preparing method, but also to the distribution of different components in the precursor. The UV-VI spectrum measurement of the transparent PLT film indicates that its optical absorption bands have extended into the visible region and a change in its absorption pattern with the increase of mean grain size was also observed. As the transparent nanocrystalline PLT thin film with small grain size possesses wider optical absorption band in range of 320-800 nm, the material of Pb_1-xLa_xTiO₃ with suitable component and mean grain size can be used in the fabrication of dye-sensitized photoelectronchemistry solar cell instead of TiO₂. And the higher photoelectric efficiency can be expected.