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Electromagnetic interference (EMI) shielding is critical for protecting electronic devices from interference generated by various sources such as power lines, radio waves, microwaves, and electronic devices. In this current study, we present a thorough investigation of the structural, magnetic, and electromagnetic properties of Y3+ doped M-type barium nano hexaferrites. Polycrystalline BaFe 12−x Y x O 19 (x = 0.0, 0.3, 0.5, 0.7, and 0.9) hexaferrites are prepared using the citrate precursor method. The results of X-ray diffraction (XRD), Rietveld refinement and Raman spectroscopy confirmed that all samples have a single-phase, and pure hexagonal crystalline structure with space group P69/mmc. This result is consistent for all the prepared compositions. The structure and dopant materials in different chemical states of the sample are determined based on the X-ray photoelectron spectroscopy (XPS) spectrum. Field emission scanning electron microscopy (FESEM) analysis showed that the particles had a distinct hexagonal morphology. The chemical composition of the prepared hexaferrites is investigated using energy dispersive X-ray analysis (EDAX). UV spectroscopy showed an inverse relationship between the molar ratio of yttrium and the band gap. Vibrating sample magnetometer (VSM) results showed a decrease in saturation magnetization (M s) and coercivity (H c) with increasing fraction of yttrium ions. The shielding efficiency (SE) of the synthesized hexa materials against EMI is evaluated using a vector network analyser (VNA). In particular, effective EMI shielding was observed in the frequency spectra of 8–12 GHz (X-band region). Among the tested compositions, BaFe 12–0.7 Y 0.7 O 19 with a thickness of 3 mm exhibited highest SE of 80.07 dB in the X-band region. The proposed yttrium-substituted barium M-type hexagonal ferrites exhibit significant reflection loss with enhanced absorption spectrum even when applied to an extremely thin 3 mm material, making it a possible preference as the radar-absorbed compound for EMI attenuators for weather monitoring, radar tracking, air traffic management, and gigahertz antennas. Furthermore, commercial applications including long-term magnetic media for recording, storing information, etc. are possible uses of the synthesised magnetic yttrium-doped barium M-type hexagonal ferrites. • Yttrium-substituted barium hexaferrite nanoparticles of M-type were successfully synthesized by the citrate precursor method. • A remarkable effectiveness in shielding electromagnetic interference is observed in the X-band frequency spectrum. • Synthesized yttrium-substituted barium hexaferrite nanoparticles are effective for electromagnetic interference shielding applications. [ABSTRACT FROM AUTHOR]

Abstract: Three new RP-type phases of the composition Sr3Fe1.7Nb0.3O7, Sr3Fe1.4Nb0.6O7 and Sr3FeNbO7 have been synthesized by the standard ceramic method. Their structure has been determined by Rietveld analysis of the powder X-ray diffraction data. The phases take up RP-type structure in the space group 14/mmm. The MO6 polyhedron is distorted. The study of electrical resistivity as a function of temperature suggests that these undergo insulator–metal transition. The magnetic susceptibility data show that the phases are anti-ferromagnetic in nature. [Copyright &y& Elsevier]

A new Ruddlesden–Popper (RP)-type phase Sr3MnTiO7-δ has been synthesised by the standard ceramic method. Its crystal structure has been solved by Rietveld analysis of the X-ray diffraction data. The X-ray diffraction studies suggest that the phase crystallizes in the tetragonal unit cell with the space group 14/mmm. Study of electrical resistivity, as a function of temperature, suggests that the conduction in the temperature range 100–300 K occurs by variable range hopping mechanism. Magnetic moment of the phase is of the order of 4.45 BM. [Copyright &y& Elsevier]

SnS x Se 1−x films can be fabricated by adjusting the Se/(Se + S) ratio by using two different source materials (SnS + SnSe or S + Se). However, maintaining a uniform composition throughout the film can be challenging when using conventional double-source methods. Here, we have developed a single-source vapor-transport-deposition (VTD) method to deposit highly compact and uniform SnS x Se 1−x alloy films with a Se/(Se + S) compositional ratio of 0.3. Furthermore, we fabricate thin-film solar cell (TFSC) devices with varying evaporation durations ranging from 3 to 7 h. By increasing the evaporation duration from 3 to 7 h, the thickness of the SnS 0.7 Se 0.3 absorber layer nearly doubled from around 1.05 µm to approximately 2.0 µm. As a result, the solar cell device (SLG/Mo/SnS 0.7 Se 0.3 /CdS/i-ZnO/AZO/Al) fabricated with a 5-h evaporation duration, which had an absorber thickness of approximately 1.55 µm and a bandgap of 1.18 eV, achieved a highest efficiency of 3.59%. In addition, its V OC , J SC , and FF were 0.284 V, 24.50 mA cm−2, and 51.3%, respectively. Furthermore, the band alignment at the SnS 0.7 Se 0.3 /CdS interface was investigated to determine the conduction band offset (CBO) and valence band offset (VBO). The results confirmed a cliff-like CBO of −0.07 eV at the SnS 0.7 Se 0.3 /CdS interface. The optimized device retained almost 99.9% of its initial efficiency after 6 months of storage in the air. [Display omitted] • Single-source vapor transport deposition of SnS x Se 1−x thin films. • Structural and morphological study of SnS x Se 1−x via varied evaporation durations. • Optimization of SnS x Se 1−x /CdS TFSCs with a competitive efficiency of 3.59% • Revealing band alignment at the SnS 0.7 Se 0.3 /CdS heterojunction interface [ABSTRACT FROM AUTHOR]