Effect of oxygen vacancy on the magnetic and electric properties in MnTiO3 ceramics

We conducted a comparative study on structural, magnetic and electric properties of MnTiO3 ceramics sintered in air (MTO-A) and nitrogen (MTO-N) to explore the impact of oxygen vacancies (OVs) on them. The X-ray diffraction patterns show that MTO-N possesses a lattice contraction induced by OVs comparing with MTO-A. Distinct spin glass (SG) with Tsg (41 K) and magnetic exchange bias (EB) are only observed in the MTO-N sample. The results indicate that OVs may well lead to the enhanced magnetization, thereby generating SG behavior. Moreover, the dielectric characteristics of MTO-A and MTO-N are investigated additionally, two disparate relaxation mechanisms of Maxwell–Wagner relaxation and OVs migration are illuminated respectively, which further support the vital function of OVs.