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Ferroelectric (FE) resistive switching has attracted considerable interest as a promising candidate for applications in non‐volatile memory technology. In this work, via judiciously controlling the defect states of oxygen vacancy through Sm‐doping, the authors obtain multiple current jumps/discrete resistance states in the resistive switching memories based on a model FE BiFeO3 (BFO). These hitherto unreported current jumps are attributed to the space‐charge‐limited current correlated with electron trapping by oxygen vacancies in the BFO film. Concurrently, oxygen vacancies serve as the pinning centers for the FE domains, leading to the domain wall creep behavior. These results illustrate the strong interplay between the defect, resistive switching, and domain wall creep behavior in FE diodes, providing a new insight into the mechanism of FE resistive switching. Overall, the large on/off ratio of ≈5 × 105, multiple resistance states, and fast switching speed of ≈30 ns, promise their potential applications in multi‐level data storage memories. [ABSTRACT FROM AUTHOR]

Ferroelectric polarization allows a depolarization electric field to separate electron-hole pairs excited by lights, and thus, the photovoltaic properties of ABO3-type films on a hard SrTiO3 or Si substrate have been extensively studied recently. However, there are a few reports on the photocapacitance and photoimpedance of these oxide films, especially on flexible substrates. In this work, the strong photovoltaic, giant photocapacitance, and photoimpedance effects were observed in the flexible (111) BiFeO3 films with natural downward polarization. The flexible mica/SrRuO3/BiFeO3/Au cells show a maximum photovoltaic efficiency at 150 °C, a 95.5% decrease in photoimpedance effects, and a 316% increase in photocapacitance effects under 405-nm-wavelength light illumination at 25 °C. Most importantly, these properties do not show obvious degradation when the device is bent to 3 mm radius for 104 times. This work is of vital importance for us to develop new flexible photoelectronic devices. [ABSTRACT FROM AUTHOR]

Photoelectrochemical water splitting provides a promising strategy for converting solar energy into chemical fuels and has attracted extensive interest. Herein, Bi 2 MoO 6 nanopillars with large surface areas were fabricated on an ITO-coated glass substrate and their photoelectrochemical properties are enhanced through appropriate manipulation of ferroelectric polarization. The Bi 2 MoO 6 photoanode with polarization orientation toward ITO shows an enhanced photocurrent density of 250 μA cm -2 at 1.23 V vs. reversible hydrogen electrode, which is 28% higher than that of pristine Bi 2 MoO 6 nanopillars without macroscopic polarization. The corresponding depolarization electric field benefits the separation of light-excited electron-hole pairs, thus minimizing the recombination of charge carriers and further enhancing the photocurrent current density. Our work offers a new strategy of Bi 2 MoO 6 -based photoelectrochemical devices with great potential of application in the conversion of solar energy into chemical fuels.