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Bismuth ferrite (BiFeO3) multiferroic nanoparticles are synthesized using a low-temperature sol–gel auto-combustion technique. The phase purity is confirmed from X-ray diffraction (XRD) measurements and microstructural, electronic, and optical studies are correlated with the particle size of the bismuth ferrite nanostructured material. We demonstrated bandgap tunability from 2.22 to 1.93 eV with an average crystallite size from 42 to 24.42 nm following the inverse quantum confinement effect dominated by the lattice strain. The degenerate d–d electronic transitions 6A1g → 4T1g and 6A1g → 4T2g from iron dominate in these nanoparticles. The decrease in the energy band gap and the corresponding red shift in the d–d charge transfer transition energies with reduced average crystallite size are attributed to the increased lattice strain and reduced unit cell volume. [ABSTRACT FROM AUTHOR]

Implementation of stealth features on advanced airborne platforms (aircrafts, unmanned air vehicles, missiles, etc.) has become a compulsion for each country, for denial/delay detection of these objects from enemy radars, during tactical missions. Apart from the shaping of the airframe, implementation of microwave-absorbing materials (MAMs) on identified locations of airborne vehicles is the only viable solution to reduce their radar cross-section (RCS) and eventually attain stealth capabilities. Numerous dielectric and magnetic class materials have been developed over the last few decades to fulfil the requirement for RCS reduction against various radars operating in different frequency ranges. In this review, a detailed representation of almost the entire range of materials used as MAMs has been provided along with their possible microwave (MW) loss mechanism to fill the gap that existed for a systematic insight on MAMs till now. The current limitations and future aspects are also discussed for the development of future stealth materials. [ABSTRACT FROM AUTHOR]

Spinel ferrite-based magnetic nanomaterials have been investigated for numerous biomedical applications, including targeted drug delivery, magnetic hyperthermia therapy (MHT), magnetic resonance imaging (MRI), and biosensors, among others. Recent studies have found that zinc ferrite-based nanomaterials are favorable candidates for cancer theranostics, particularly for magnetic hyperthermia applications. Zinc ferrite exhibits excellent biocompatibility, minimal toxicity, and more importantly, exciting magnetic properties. In addition, these materials demonstrate a Curie temperature much lower than other transition metal ferrites. By regulating synthesis protocols and/or introducing suitable dopants, the Curie temperature of zinc ferrite-based nanosystems can be tailored to the MHT therapeutic window, i.e., 43–46 °C, a range which is highly beneficial for clinical hyperthermia applications. Furthermore, zinc ferrite-based nanostructures have been extensively used in successful pre-clinical trials on mice models focusing on the synergistic killing of cancer cells involving magnetic hyperthermia and chemotherapy. This review provides a systematic and comprehensive understanding of the recent developments of zinc ferrite-based nanomaterials, including doped particles, shape-modified structures, and composites for magnetic hyperthermia applications. In addition, future research prospects involving pure ZnFe2O4 and its derivative nanostructures have also been proposed. [ABSTRACT FROM AUTHOR]

The materials showing write once read many (WORM) types of resistive switching characteristics are potential candidates for permanent storage. The negative differential resistance‐based memory devices have the potential to perform like nonlinear systems together with resistive switching simultaneously. The successful synthesis of Bi‐rich Bi12FeO20 sillenite material as phase pure thin film on fluorine tin oxide (FTO) using a solution process together with thermally deposited copper (Cu) as the top contact is demonstrated. Cu/Bi12FeO20/FTO/Glass resistive random‐access memory (RRAM) devices show the WORM characteristics with Ion/Ioff ratio103 and negative differential resistance simultaneously. Further, Bi12FeO20 active material also shows nonvolatile characteristics with analog switching for 200 cycles or more with large retention time, ≈5 × 103 s, and endurance for 103 cycles, substantiating the stability of the device. The space charge limited conduction and Schottky mechanisms explain the formation of a conductive filament in a high resistance state (HRS) and rupturing of a conductive filament in a low resistance state (LRS). The observed negative differential resistance is attributed to trapping, detrapping, and Schottky barrier interface between the top electrode and active layer together with ambient humidity. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO 3 ) multiferroic nanoparticles are synthesized using a low-temperature sol-gel auto-combustion technique. The phase purity is confirmed from X-ray diffraction (XRD) measurements and microstructural, electronic, and optical studies are correlated with the particle size of the bismuth ferrite nanostructured material. We demonstrated bandgap tunability from 2.22 to 1.93 eV with an average crystallite size from 42 to 24.42 nm following the inverse quantum confinement effect dominated by the lattice strain. The degenerate d-d electronic transitions 6 A 1g → 4 T 1g and 6 A 1g → 4 T 2g from iron dominate in these nanoparticles. The decrease in the energy band gap and the corresponding red shift in the d-d charge transfer transition energies with reduced average crystallite size are attributed to the increased lattice strain and reduced unit cell volume.

Spinel ferrite-based magnetic nanomaterials have been investigated for numerous biomedical applications, including targeted drug delivery, magnetic hyperthermia therapy (MHT), magnetic resonance imaging (MRI), and biosensors, among others. Recent studies have found that zinc ferrite-based nanomaterials are favorable candidates for cancer theranostics, particularly for magnetic hyperthermia applications. Zinc ferrite exhibits excellent biocompatibility, minimal toxicity, and more importantly, exciting magnetic properties. In addition, these materials demonstrate a Curie temperature much lower than other transition metal ferrites. By regulating synthesis protocols and/or introducing suitable dopants, the Curie temperature of zinc ferrite-based nanosystems can be tailored to the MHT therapeutic window, i.e. , 43-46 °C, a range which is highly beneficial for clinical hyperthermia applications. Furthermore, zinc ferrite-based nanostructures have been extensively used in successful pre-clinical trials on mice models focusing on the synergistic killing of cancer cells involving magnetic hyperthermia and chemotherapy. This review provides a systematic and comprehensive understanding of the recent developments of zinc ferrite-based nanomaterials, including doped particles, shape-modified structures, and composites for magnetic hyperthermia applications. In addition, future research prospects involving pure ZnFe 2 O 4 and its derivative nanostructures have also been proposed.