First-principles investigation of the ground state, structural phase transition, and magnetic ordering of strained BiVO3

Ground state, structural, and magnetic phase transitions of strained BiVO3 were investigated using the first-principles calculation based on the self-interaction corrected local density approximation + U functional. The calculated total energy indicated that the ground state structure for BiVO3 was a monoclinic P21/a phase and ferromagnetic ordering is predicted to be the magnetic ground state. Furthermore, it was found that BiVO3 are metastable compounds under strain effects, where several structural phase transitions were predicted from the monoclinic P 21 / a phase to the orthorhombic P b n m phase (at compressive volumetric strain) and to monoclinic C m and C c phases (at expansive volumetric strain). Furthermore, calculations on electronic band structure and density of states for the monoclinic P21/a phase and the monoclinic C c phase of BiVO3 with ferromagnetic ordering were conducted. The calculated band structure predicted a small energy gap with a direct energy bandgap of 0.456 eV and an indirect energy gap of 0.466 eV. Interestingly, the obtained results revealed that the BiVO3 calculated density of states exhibited Mott-Hubbard insulator type. Therefore, the ground state monoclinic C c phase of strained BiVO3 with ferromagnetic ordering is suggested as a new candidate for multiferroic materials at room temperature and a visible light driven photocatalytic/photovoltaic effect. The obtained results in this study could provide valuable theoretical information on BiVO3 under strain effects, which could open new opportunities for future research and technological applications.