Semiconducting and Photovoltaic Ferroelectrics

Stress-mediated solution deposition method to stabilize ferroelectric BiFe1-xCrxO3 perovskite thin films with narrow bandgaps

“…This phenomenon is associated to the ferroelectric domains present in the polarized film, which work as internal junctions for the separation of the photoexcited electron and hole pairs. [28,64] This is an important outcome from our point of view, since it demonstrates the coupling effect between the ferroelectric and the photovoltaic properties [6,12,28,65,66] in these HP metastable BFCO perovsite thin films. The Incident Photon to Current Efficiency (IPCE) as a function of wavelength of these devices, using the HP metastable BFCO perovskite films as the only light absorber, is shown in Figure S4h.…”

“…Thus, simply considering a planar capacitor configuration, using transparent and high conductive electrodes would increase the amount of light arriving at the film. [6,28,65] Besides, decreasing the film thickness (distance between electrodes) would produce an increase in VOC. Work is currently in progress in our group to optimize these properties in these films.…”

“…[6,13] Solid solutions of BiFeO3 and BiMO3 perovskites with M = Cr, Mn, Co or Ni, show high ferroelectric polarization and lower bandgap in relation to the pure BiFeO3. [14][15][16][17][18] However, the preparation of these BiMO3 perovskites have only been attained as powders or as bulk ceramics applying unconventional synthesis conditions like high temperature (HT) and high pressure (HP). [17,19,20] Recently, the application of these compounds as solar absorbers has been demonstrated for solid solutions of BiFeO3 and BiCrO3 (also formulated as BiFe1-xCrxO3, herein BFCO), where large amounts of chromium are introduced in the double perovskite (i.e., BiFe0.5Cr0.5O3).…”