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Interface-driven multifunctional facets are gearing up in the field of science and technology. Here, we present the interface-activated resistive switching (RS), negative differential resistance, diode behavior, and ultraviolet (UV) light sensing in nanosheet-based hybrid devices. A hybrid device i.e., titanium dioxide nanosheet (TiO 2 -NS)/poly(dimercaptothiadiazoletriazine)[Poly(DMcT-CC)] is fabricated by spin coating Poly-(DMcT-CC) polymer on hydrothermally as-grown TiO 2 -NS. The pristine devices of both materials show either small or no magnitude of RS, but the hybrid device shows highly enhanced RS of nearly four orders due to the formation of a p−n junction at the NS/polymer interface. The resistive random access memory feature appears to be more prominent in the hybrid device i.e., high and low current states are found to be stable in repetitive cycles since the interface acts as a trapping center for the carriers. The UV sensing ability of the hybrid device has been demonstrated by a threefold increment in a current at 60 mV. The impedance spectroscopy has been employed to show that the multifunctional features are directly associated to the NS/polymer interface, which deduce that the manipulation of such interfaces can pave the way for developing the hybrid structures.

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The present work reports the influence of Lanthanum (La) substitution on the structural, optical, electrical, and magnetic properties of bismuth ferrite (BiFeO 3 ) nanoparticles (NPs). The compositions of Bi 1−x La x FeO 3 (0% < x < 20%) NPs, with 5% Bi-excess, were synthesized through sol-gel conventional route. The XRD results suggest the formation of rhombohedral perovskite structure (R3c space group) along with a minor secondary phase. The crystallite size calculated from XRD and FESEM was observed to decrease from 60.0 to 40.0 nm with an increase in La content. The bandgap calculated using UV-Vis spectroscopy was found to decrease with La doping, and PL spectroscopy infers formation of defects in La-BFO NPs. The P-E loop studies reveal that La-doped BFO exhibits ferroelectric behavior at room temperature. The various parameters such as spontaneous polarization, dielectric constant, and distribution parameter of relaxation time measured from the electrical investigation were found to increase up to 5% La doping BFO then start decreasing with further increase in the La content in BFO. The impedance spectra of La-BFO was fitted using the theory of Cole-Cole with R(C(R(QR)))(CR) model. It is observed that La-concentration above 5% generates excess space charge which might cross the threshold to start conduction resulting in degrading of multiferroic properties. The DC magnetization study revealed the ferromagnetic behavior of the samples at room temperature. It is observed that La substitution affects the shape of the magnetization hysteresis curve beyond 5% La-concentration, and transforming it to a neck-like formation providing evidence for the spin-canting effect in the samples. These results make La-doped BiFeO 3 NPs a propitious candidate for the multiferroic applications like highdensity data storage devices and supercapacitors.