Stability of non-metal dopants to tune the photo-absorption of TiO2 at realistic temperatures and oxygen partial pressures: A hybrid DFT study
Titanium dioxide (TiO2) anatase, is one of the most abundant, functionally versatile oxide materials, with applications in the field of opto-electronic devices and solar cell conversion efficiency. Since TiO2 has a large bandgap of 3.2 eV, that severely limits the photoabsorption in the visible region range. Doping-mediated modulation is one of the most pragmatic approaches in the pursuit to improve the photocatalytic and solar energy conversion efficiencies of TiO2. We report here using state-of-the-art hybrid density functional and ab initio atomistic thermodynamics the stability and meta-stability of different non-metal dopants X (X= N, C, S, Se) as a function of charge state at realistic temperature and pressure. We have obtained that charge play an important role in providing the stability by carefully analyzing the individual effect of bond-making/breaking and charge carrier trapping energies.
Link : Nature Sci. Rep. 9, 11427 (2019)
Pooja Basera and Dr. Saswata Bhattacharya
Department of Physics