The electronic structure and infrared spectroscopy of Al-H and Fe-H codoped rutile-type TiO2

Rutile from Shuanghe and Bixiling area in the Dabie Orogen were investigated by Micro- Fourier transform infrared spectroscopy (FTIR). The results show that all the grains exhibit a sharp band near 3280 cm-1 or 3295 cm-1. Two structures have been suggested about the position of H in rutile, namely the chanel center (CC) and basal octahedron edge (BOE) models. The lattice structure and electronic band structure of Al—H and Fe—H codoped rutile TiO2 has been calculated by first-principles method. According to O—H bond vibration frequency of FTIR and O—H…O bond distance between O—O of computational results, we deduce that modified channel center (MCC) model is more reasonable. The calculation results indicate that the t2g state of Fe overlaps with the O 2p state, which will narrow the band gap and lead to red shift in optical absorption spectra.