Study about TiO2/Nb2O5 Composite Electrode Thin Films for Photovoltaic Applications
Date
2023Author
Njagi, John
Aduda, Bernard Odhiambo
Nyongesa, Francis Wanjala
Musembi, Robinson Juma
Metadata
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Nanopowders can be defined as powdered materials with individual particles in nanometer scale or materials with crystalline in nanometer scale. Nanoparticles (NPs) are made up of a large amount of atoms or molecules bonded with each other with a total size varying from 1 nm to around 100 nm. Due to their very small sizes, NPs possess an extraordinarily high surface area-to-volume ratio, which changes their physical-chemical properties compared to their macroscale counterparts. Nano sized powders of TiO2 (titanium dioxide) and Nb2O5 (Niobium (V) oxide) were used to fabricate TiO2/Nb2O5 composites thin films by EPD (electrophoretic deposition) technique. In an EPD cell, pellets of magnesium nitrate hexahydrate and metal oxide powders were suspended in propan-2-ol. 1.2 cm apart, the electrodes were submerged in the suspension with a DC potential supplied across them. Through visual examination and analysis of UV-Vis-NIR spectrophotometer spectra, key EPD process parameters, including as the applied DC electric field, deposition duration, and solid concentration in suspension, were improved. The films with deposition times of 90 s, powder concentrations of 0.01 g/40 mL, and direct current (DC) voltage of 35 V had the maximum transmittance (55%) of all the samples. XRD micrographs confirmed that TiO2 and Nb2O5 particles were presented in the composite film. SEM (scanning electron microscope) micrographs of the composite electrode thin films showed that porous films of high quality with well controlled morphology were deposited by using the EPD technique.
