Electronic Bulk and Surface Properties of Titanium Dioxide Studied by DFT-1/2

Area of Science:

• Materials Science
• Solid State Physics
• Computational Chemistry

Background:

• Transparent conductive oxides are vital for optoelectronics and photovoltaics.
• Titanium dioxide (TiO2) is a key material in this class, with rutile and anatase being important phases.

Purpose of the Study:

• To investigate the electronic bulk properties of rutile and anatase TiO2 phases.
• To calculate the ionization potentials (IPs) and work functions (WF) of their (001) surfaces.
• To understand how surface oxygen stoichiometry affects these properties.

Main Methods:

• Density Functional Theory (DFT) with the DFT-1/2 method was employed.
• Electronic band structures of bulk TiO2 were calculated.
• Surface properties (IP and WF) were computed for rutile and anatase (001) surfaces.

Main Results:

• The DFT-1/2 method provided a quantitatively accurate description of TiO2 electronic band structures.
• Calculated IPs and WFs for rutile and anatase (001) surfaces were obtained.
• The influence of varying surface oxygen stoichiometry on IP and WF was evaluated.

Conclusions:

• The DFT-1/2 method is effective for describing the electronic properties of TiO2 phases and their surfaces.
• Surface oxygen stoichiometry significantly impacts the ionization potential and work function.
• This work provides insights for optimizing TiO2 for device applications.