Inorganic photovoltaic cells based on BiFeO₃: spontaneous polarization, lattice matching, light polarization and their relationship with photovoltaic performance

Abstract

Inorganic ferroelectric perovskite oxides are more stable than hybrid perovskites. However, their solar energy harvest efficiency is not so good. Here, by fabricating a serious of BiFeO 3 based devices (solar cells), we investigated four factors that influence the photovoltaic performance, including spontaneous polarization, mechanism of leakage current suppression by Co element substitution, terminated atoms species in the heterogeneous structure with the electrode, and polarized light irradiation with the framework of density functional theory combined with non-equilibrium Green's function theory under built-in electric field or finite bias. The results showed that 1) the photocurrent is larger only under a suitable electronic band gap rather than larger spontaneous polarization; 2) the BiFeO 3 based solar cell degradation could be suppressed by Co element substitution due to the dark current suppression; 3) the photocurrent reaches the largest in Bi 3+ ions terminated interface than the case of Fe 3+ or O 2with SrTiO 3 devices; 4) the power conversion efficiency could be largely enhanced if the polarized direction of the monochromatic light is perpendicular to the spontaneous polarization direction. The results will deepen the understanding of experimental results of BiFeO 3 based solar cells.

Electronic and electrocatalytic properties of PbTiO3: unveiling the effect of strain and oxygen vacancy

“…The HER over-potential seems better than that found for the BaTiO 3 slab modulated by polarization states. 70,104 This finding can be supported by the experimental finding of ref. 17, where the experimental evidence shows that the oxygen vacancies in PbTiO 3 show the spontaneous formation of active sites during preparation pro-…”

Crossover between Bulk and Interface Photovoltaic Mechanisms in a Ferroelectric Vertical Heterostructure

“…The optical excitation increases as the rotation angle increases, and the strongest absorption occurs at light polarization perpendicular to the [110] PC direction. The absorption anisotropy is consistent with the band structure of BiFeO 3 (R3c) [50,51] and is attributed to the highly distorted FeO 6 octahedra.…”

Self-Powered UV Photodetector of TiO2 with BaTiO3 Surface Modification and Light-Controlled Logic Circuits Application

“…Ferroelectric semiconductor materials have ferroelectric photovoltaic effects due to the presence of an intrinsic spontaneous polarization electric field or depolarization field in the bulk, which can drive photogenerated carrier separation. In recent years, ferroelectric materials, such as KNbO 3 , Pb­(Zr,Ti)­O 3 , BaTiO 3 (BTO), and BiFeO 3 , , with a ferroelectric photovoltaic effect have been used in photocatalysis, PDs, and solar cells. The depolarization field generated in the ferroelectric material after applying the bias can effectively modulate the barrier height, the depletion region width, and the magnitude of the built-in electric field in ferroelectric-based PDs to improve the carrier transport characteristics. , However, the large dielectric constant and insulating nature of ferroelectric materials lead to low electron mobility and poor material conductivity.…”