| Summary: | Well ordered and vertically oriented titania nanotubes (TNT) are of great scientific interest due to their high surface area, fewer interfacial grain boundaries and excellent charge transfer between interfaces; all are critical properties in photoelectrochemical and photocatalysis application. In this study, self-assembled TNT electrodes were synthesized by anodization of pure Ti in 0.5 wt.% NH4F solution (NH4F/H2O), in mixture of aqueous-organic solution (NH4F/H2O/EG) and in an organic solution (NH4F/EG). Choice of electrolytic medium has an influence on the crystalline structure, regularity, elemental composition and band gap of TNT. All the samples showed a red shift and stronger absorption in the wavelength between 500-700 nm ascribed to the surface colour and increase crystallinity upon calcination. TNT formed in NH4F/H2O solution has the highest direct band gap of 3.34 eV due to quantization effect. From Liner Sweep Photovoltammetry analysis, the lowest photocurrent was recorded for TNT anodized in NH4F/H2O and a twofold and fivefold increase on the magnitude of photocurrent was obtained for those formed in NH4F/H2O/EG and NH4F/EG solution, respectively. Hence, highest photoefficiency of 2.79 % was recorded for TNT formed in NH4F/EG probably due to the formation of longer length tube. © 2016, Malaysian Society of Analytical Sciences. All rights reserved.
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