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ELECTROPHORETIC DEPOSITION OF TIO2 THIN FILMS AND ITS APPLICATION IN PHOTOCATALYSIS AND SOLAR CELLS, 2015

Electrophoretic deposition (EPD) is similar to electrolysis reaction although, instead of deposit... more Electrophoretic deposition (EPD) is similar to electrolysis reaction although, instead of deposition
from solution, particles are deposited from suspension. Nano sized powders of TiO2 (titanium
dioxide) was used to fabricate TiO2 composites thin films by electrophoretic deposition technique.
0.02g of Titanium oxide powder with 0.02g magnesium nitrate hexahydrate pellets, were suspended
in 40mL of propan-2-ol in a glass beaker. The electrodes were place 1.2 cm apart, they were partially
immersed in the suspension and a DC potential range of 15-55 V applied across them. Various EPD
parameters such as applied DC voltages, deposition time and solid concentration in suspension, were
optimized through visual inspection, profilometer, UV-Vis-NIR spectrophotometer and a 10-4g
precision balance. As the applied voltage increased, the film thickness and mass increased.
Thickness and mass of the TiO2 films increased linearly during the initial period of EPD but the
deposition rate subsequently decreased and attained a constant value for longer durations. The
highest transmittance of 35% was observed in the film electrophoretically deposited at 35 volts;
likewise the highest mass and thickness were obtained at the 35 voltage-deposited films.
Keywords: Electrophoretic deposition (EPD), Photocatalytic reaction, TiO2 composite thin films,
UV applications, band gap, zeta potential.

ELECTROPHORETIC DEPOSITION OF TIO2 THIN FILMS AND ITS APPLICATION IN PHOTOCATALYSIS AND SOLAR CELLS, 2015

Electrophoretic deposition (EPD) is similar to electrolysis reaction although, instead of deposit... more Electrophoretic deposition (EPD) is similar to electrolysis reaction although, instead of deposition
from solution, particles are deposited from suspension. Nano sized powders of TiO2 (titanium
dioxide) was used to fabricate TiO2 composites thin films by electrophoretic deposition technique.
0.02g of Titanium oxide powder with 0.02g magnesium nitrate hexahydrate pellets, were suspended
in 40mL of propan-2-ol in a glass beaker. The electrodes were place 1.2 cm apart, they were partially
immersed in the suspension and a DC potential range of 15-55 V applied across them. Various EPD
parameters such as applied DC voltages, deposition time and solid concentration in suspension, were
optimized through visual inspection, profilometer, UV-Vis-NIR spectrophotometer and a 10-4g
precision balance. As the applied voltage increased, the film thickness and mass increased.
Thickness and mass of the TiO2 films increased linearly during the initial period of EPD but the
deposition rate subsequently decreased and attained a constant value for longer durations. The
highest transmittance of 35% was observed in the film electrophoretically deposited at 35 volts;
likewise the highest mass and thickness were obtained at the 35 voltage-deposited films.
Keywords: Electrophoretic deposition (EPD), Photocatalytic reaction, TiO2 composite thin films,
UV applications, band gap, zeta potential.