First-principles study of Bi and Al in orthorhombic PbZrO3

• The microscopic and electronic structures of Bi/Al-doped PZO were theoretically studied.
• Bi atom is likely to substitute on either Pb or Zr atom without the need of Al atom.
• The antiferroelectric property of PZO can be enhanced by doping with only Bi atom.

Lead zirconate PbZrO3 (PZO) is one of the most important ceramic materials due to its antiferroelectric property, which can be used in many technological applications. Due to the toxicity of Pb, there is an attempt to replace Pb with other non-toxic elements. It has been reported that doping orthorhombic-PZO with Bi and Al atoms could stabilize the antiferroelectric property in a wide temperature range and reduce the lead content in the material. In this work, we used first-principles calculations based on density functional theory to investigate the microscopic and electronic structures of Bi and Al defects in orthorhombic-PZO. Our calculated defect formation energies revealed that Bi atom can substitute on either Pb site (A-site) or Zr site (B-site); depending on the Fermi-level as well as the crystal growth condition. On the other hand, Al atom is likely to substitute only on the Zr site. In addition, our calculations revealed that there is only a small binding between BiPb and adjacent AlZr or BiZr with the binding energies of ∼0.2 eV. This indicates that BiPb and AlZr (or BiZr) are unlikely to form complexes.