The investigation of the electronic structure of P-ion implanted TiO2 thin films (E = 30 keV, D = 1 × 1017 cm−2) with anatase structure is performed by X-ray photoelectron spectroscopy (XPS) measurements (core levels and valence bands) and first-principles density functional theory (DFT) calculations. It is found that the XPS P 2p-spectra reveal the presence of two signals at 134.2 and 130.3 eV which can be attributed to the formation of P–O (with P5+ ions) and P–Ti (with P3− ions) bonds, respectively. This means that both cationic (P → Ti) and anionic (P → O) substitution take place in P-ion implanted anatase thin films. This conclusion is confirmed by DFT calculations which show that the XPS valence band structure of P:TiO2 can be reproduced only under mixed substitution. The presence of two kinds of phosphorus ions (P5+ and P3−) in ion-implanted TiO2 can be useful for developing new multifunctional advanced materials with configurable properties for a wide range of applications.
- anatase structure
- density functional theory
- TiO thin films
- X-ray photoelectron spectroscopy