Effect of doping on electronic structure and photocatalytic behavior of amorphous TiO2.
نویسندگان
چکیده
Visible light photocatalysts based on doped crystalline forms of titanium dioxide (TiO2) have attracted significant scientific attention in recent decades. Amorphous TiO2, despite many merits over crystalline phases, has not been studied as thoroughly. In this paper, an in-depth analysis of the electronic properties of doped amorphous TiO2 is performed using density functional theory with Hubbard's energy correction (DFT + U). Monodoping with p-type (N) and n-type (Nb) dopants shows appreciable bandgap reduction, but leads to recombination centers due to the presence of uncompensated charges. To resolve this issue, charge compensation via codoping is attempted. The charge compensated codoping not only reduces the bandgap by 0.4 eV but also eliminates the bandgap states present in monodoped systems responsible for charge carrier recombination. Furthermore, the localized tail states present in the aTiO2 system are eliminated to a large extent which leads to a decrease in the charge recombination and an increase in the charge migration. Thus, appropriate doping of amorphous TiO2 may lead to an alternative route for the development of visible light photocatalysts.
منابع مشابه
RETRACTED: Effects of N Doping on Structure and Improvement Photocatalytic Properties of Anatase TiO2 Nanoparticles
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ورودعنوان ژورنال:
- Journal of physics. Condensed matter : an Institute of Physics journal
دوره 25 47 شماره
صفحات -
تاریخ انتشار 2013