Comparison of Nb- and Ta-doping of anatase TiO2 for transparent conductor applications

Nb- or Ta-doped anatase TiO2 was shown to be a viable candidate for replacing indium-tin-oxide as a transparent conductive oxide. Calculating the electronic structures we find that Ta has the considerably higher solubility and lower optical effective mass of the two dopants. Our calculations also show that a reducing atmosphere is necessary for efficient dopant incorporation, and oxygen vacancies do not necessarily play a role in their activation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4733350]