Field-induced large strain and strong green photoluminescence in (Ho,Sb)-modified (Bi0.5Na0.5)0.945Ba0.065TiO3 multifunctional ferroelectric ceramics

(Ho,Sb)-modified (Bi0.5Na0.5)0.945Ba0.065TiO3 (BNBT6.5) multifunctional ferroelectric ceramics were fabricated by a conventional solid-state reaction method. Results showed that (Ho, Sb)-modified BNBT6.5 materials exhibited a bright green photoluminescence while simultaneously obtaining a large electric-field-induced strain of 0.37% (80 kV/cm) in samples with x = 0.50% due to the appearance of an ergodic relaxor phase at zero field. Under the electric field, the ergodic relaxor phase could reversibly transform to ferroelectric phase. As a result, the strain is very resistant to field cycling due to the reversible field-induced phase transition between the ergodic relaxor and ferroelectric phase, giving the materials attractive for its good fatigue resistance. Besides the excellent strain properties, (Ho, Sb)-modified BNBT6.5 host exhibits a bright photoluminescence with a strong green emission located at around 549 nm owing to the 5S2→5I8 transition under the 451 nm light excitation at room temperature. As a multifunctional material, (Ho,Sb)-modified BNBT6.5 ferroelectric materials showed great potential in optical-electro integration and coupling device applications.