Role of N Doping in the Reduction of Titania Nanostructures

Abstract

The effect of N-doping of titania (TiO 2 ) nanoparticles (NPs) on their reduction through neutral O vacancy (O vac ) formation is investigated using all electron density functional theory-based calculations, including hybrid density functionals, and taking the bipyramidal anatase (TiO 2 ) 84 NP as a realistic model. The location of the N dopant is systematically analyzed, including O substitution in the (TiO 2 ) 84 structure and N occupying interstitial regions. Our computational study concludes that interstitial N doping is more favorable than N substituting O atoms and confirms that the presence of N reduces the energy gap. In the N-doped NP, O vac formation is more favored than in undoped NP but less than in the N-doped bulk, which has important consequences.

Understanding the Chemical Bond in Semiconductor/MXene Composites: TiO2 Clusters Anchored on the Ti2C MXene Surface

“…With the goal of improving the photocatalytic performance of titania derived materials, considerable efforts have been carried out in various directions. For instance, one can modify the morphology and dimension of TiO 2 nanoparticles, [1,24–26] doping with metal and non‐metal atoms, [27–32] or coupling titania with metals or semiconductors creating complex structures such as composites and heterostructures [33–39] . This structural engineering procedure at the nanoscale makes it possible to modulate the energy gaps and to extend the lifetime of photogenerated carriers separating the photogenerated electrons and holes, and thus, increasing somehow its photocatalytic efficiency [40] .…”