Synthesis and structural phase transformation study of co-doped V/Fe and V/Mn Titanium oxide: An experimental and DFT correlated study

Abstract

TiO2 plays an essential role in both experimental and theoretical fields of research because of its intriguing electrical structures and broad band gap. Large-scale uses of TiO2 are primarily based on its great efficiency in photocatalysis, pigmenting, solar cells, fuel cells, solar cells, various sensors, pollution control systems, waste management, and self-cleaning glass coating materials, as well as food, paint, cosmetics, UV protection, and other applications. It is used to produce hydrogen by splitting water and to cleanse contaminated air or water, therefore it is also ecologically friendly. Antifogging and self-cleaning coatings made of TiO2 have been utilised on glass. It's also approved for use as a food and medicinal ingredient. TiO2 have versatile application and it includes its application as a molecular sieve in oxy-concentrator. The demand of oxy-concentrator has increased due to current covid scenario as the death rate is increased due to unavailability of oxygen cylinders. TiO2 adsorbents have a higher working capacity and selectivity for air separation by preferentially adsorbing nitrogen from air for oxygen production. A theoretically supported experimental study of the TVFO and TVMO solid solution is being reported for the first time. Correlation of structural change was extensively investigated using x-ray diffraction (XRD) measurements, Raman and density functional theory (DFT) calculation. A detailed study of the structural lattice parameters, bond lengths, bond angles, vibrational and electronic properties have been emphasized. All the above parameters show a strong correlation with the structural change. The vibrational properties were studied experimentally and supported by DFT phonon calculations, specifying the displacement pattern (eigen vectors) corresponding to each mode which provides deeper insight into the lattice dynamics of the compounds. The optoelectronic modifications in the band properties were studied experimentally and theoretically. Considerable band gap tuning of UV to visible range was observed for TVMO samples which is important from the prospective of application. Hence, this manuscript is an in-depth analysis of the structure correlated study of the TVFO and TVMO solid solution.