The Effect of Multi-Fields Synergy from Electric/Light/Thermal/Force Technologies on Photovoltaic Performance of Ba_0.06Bi_0.47Na_0.47TiO₃ Ferroelectric Ceramics via the Mg/Co Substitution at A/B Sites

Currently, it is widely reported that the photovoltaic effect in ferroelectric materials can be promoted by the application of a piezoelectric force, an external electric field, and intense light illumination. Here, a semiconducting ferroelectric composition is introduced, (1-x) Ba0.06Bi0.47Na0.47TiO3-xMgCoO(3) (abbreviated as xMgCo, where x = 0.02-0.08), synthesized through Mg/Co ions codoping. This process effectively narrows the optical bandgaps to a spectrum of 1.38-3.06 eV. Notably, the system exhibits a substantial increase in short-circuit photocurrent density (J(sc)), by the synergy of the electric, light, and thermal fields. The J(sc) can still be further enhanced by the extra introduction of a force field. Additionally, the J(sc) also shows an obvious increase after the high field pre-poling. The generation of a considerable number of oxygen vacancies due to the Co2+/Co3+ mixed valence state (in a 1:3 ratio) contributes to the reduced optimal bandgap. The integration of Mg2+ ion at the A-site restrains the loss and sustains robust ferroelectricity (P-r = 24.1 mu C cm(-2)), high polarizability under an electric field, and a significant piezoelectric coefficient (d(33) = 102 pC N-1). This study provides a novel perspective on the physical phenomena arising from the synergy of multiple fields in ferroelectric photovoltaic materials.