First-principles investigation of metal-doped cubic BaTiO₃

Highlights: • Electronic properties of metal-doped cubic BaTiO₃ are studied by DFT calculations. • Most transition-metal doping can effectively reduce the band gap of BaTiO₃. • The effective mass can be reduced by doping BaTiO₃ with metals. • Substituting Ti with Fe or Mo could improve the photoelectric properties of BaTiO₃. - Abstract: The electronic properties of metal-doped cubic BaTiO₃ have been investigated using first-principles calculations. Through systematic analysis on effects of various metals doping through substituting Ti with the main group, 3d and 4d transitions metal atoms, we show that most transition metal doping can effectively reduce the band gap of BaTiO₃. The partial density of states analysis indicates that different doping elements have different effects on the band-gap engineering. The effective mass of BaTiO₃ before and after doping was further analyzed. And we found that the hole effective mass apparently decrease after Fe, Cu, Zn, Mo, and Ag doping, which could lead to increase of hole mobility and charge transfer enhancement. The calculation results showed that substituting Ti with Fe or Mo would be more effective for improving the photoelectric property of BaTiO₃. Our theoretical calculations provide useful insights and beneficial guidance into experimental study of BaTiO₃ in the photoelectric applications.