Abstract:
In this work Ti-Si and Si-Ti-Zr binary and ternary mixed oxide nanocomposites were synthesized
through sol-gel route. The structural and optoelectronic properties characteristics analyzed
using the data generated from PL, UV-vis. and XRD spectrometry. The binary and ternary
nanocomposite were synthesized with different zirconia content and calcination temperatures
using Ti(OC3H7)4 (titanium(IV) propoxide) (TTIP), Si(OC2H5)4 (tetraethylorthosilicate)
(TEOS), and Zr(OCH2CH2CH3)4 (zirconium(IV) Propoxide) precursors. The prepared samples
were characterized using PL, XRD and UV-Vis for their structural and optoelectronic
characteristics. The PL spectra analysis showed that the addition of limited amount of ZrO2
(5%) to Ti-Si binary mixed oxide retarded the recombination rate of photo-exited electron. From
the XRD analysis, it was seen that adding limited amount of ZrO2, decreased the average
crystallite size of the nanocomposite, and the smallest average crystal size found was 12.9 nm
for Ti-Si-5%Zr calcined at 500oC. The UV-Vis analysis also confirmed that addition of ZrO2
improved the absorption band to the smallest band-gap energy, which may have resulted from
quantum size effect. The bandgap energy of the prepared ternary nanocomposite varied from
2.18 eV to 2.77 eV and the smallest band-gap energy found was 2.18 eV for Ti-Si-5%Zr calcined
at 500oC, whereas the prepared binary nanocomposite calcined at 300oC was 3.07 eV. The
above properties obtained as the result of formation of ternary heterojunctions clued the
possible application of such system for solar cell, artificial photosynthesis and photocatalytic
applications
