Enhanced dielectric properties of N-doped TiO2 and its photocatalytic activity in sunlight

In the present work TiO2 was synthesized by using TiCl3 and nitrilotriacetic acid and HNO3 (TC). Synthesized TiO2 was found to be with smaller particle size with high surface area. Synthesized TiO2 shows formation of mixed phases and is confirmed from the XRD analysis. Dielectric properties of the synthesized TiO2 has been investigated for large domain signal frequencies. Dielectric constant of TC increases than that of DP-25 and shows high tangent loss. High (Ac) Alternating current conductivity was obtained for TC than the Degussa commercial TiO2(DP-25). Point of zero charge (PZC)measurements were carried out to find the charge on the surface of the catalyst. The nitrogen doping in the sample TC was confirmed from the XPS spectrum. Photocatalytic activity of the synthesized TiO2 was studied by selecting methylene blue dye as common pollutant in sunlight. The high photocatalytic activity was shown by catalyst TC with N doping and anatase-rutile mixed phase. N doping in the sample has improved the light response and further facilitate the absorption of photons to produce electron-hole pairs under sunlight reaction. Nitrogen doping and presence of mixed phase inhibit the recombination of photoinduced carriers and thus increase the quntum efficiency of TC photocatalyst.

Automated summary

In this study, TiO2 was synthesized using TiCl3, nitrilotriacetic acid, and HNO3. The synthesized TiO2 showed smaller particle size and higher surface area. XRD analysis confirmed the formation of mixed phases in the synthesized TiO2. The dielectric properties of the synthesized TiO2 were investigated for large domain signal frequencies. Compared to Degussa commercial TiO2 (DP-25), the synthesized TiO2 had higher dielectric constant and tangent loss. Point of zero charge (PZC) measurements were conducted to determine the charge on the catalyst surface. Nitrogen doping in the TC sample was confirmed by XPS spectrum. The photocatalytic activity of the synthesized TiO2 was studied using methylene blue dye as a common pollutant under sunlight. The catalyst TC, with nitrogen doping and anatase-rutile mixed phase, exhibited high photocatalytic activity. Nitrogen doping and the presence of a mixed phase inhibited the recombination of photoinduced carriers, thereby increasing the quantum efficiency of the TC photocatalyst.