Pakistan Institute of Nuclear Science and Technology

Bimetallic nanoparticles (BMNPs) composed of coinage metals are receiving substantial attention due to their high stability, versatility, and biocompatibility compared with single-metal nanoparticles. Among these, silver-copper (Ag-Cu) BMNPs stand out as a particularly promising class of materials. The combination of silver and copper produces synergism, enabling them to function as an efficient material for several applications at a relatively low cost compared with other coinage metals such as gold and platinum. Considering the emergence of Ag-Cu BMNPs in material science, this review provides an overview of the synthesis methods, including physical, chemical, and biological methods, outlining their advantages, limitations, and practical considerations. The wide range of their potential applications is also examined, encompassing catalysis, medicine, agriculture, biosensing, electronics and optical technologies, and surface-enhanced Raman spectroscopy. Special emphasis is given on how factors such as atomic arrangement, mixing behavior, particle size, shape, and surface characteristics influence their performance. Overall, Ag-Cu BMNPs emerge as cost-effective, adaptable, and high-performance nanomaterials with considerable promise for addressing contemporary technological and environmental challenges.

Wheat gluten is an insulator with plasticizer dependency, which limits its functional applications, such as its use in conductive devices. The current study addresses this issue by presenting a solvent-assisted, non-swelling, hydraulic compaction method that can promote the interfacial localization of carbon nanofillers, such as carbon black and carbon nanotubes, while preventing the main protein structure from being damaged. The prepared wheat gluten-based pellets were characterized thoroughly for their structural, morphological, and conductive parameters by four-point probe analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, energy-dispersive X-ray spectroscopy, zeta potential, and confocal laser scanning microscopy. The transition in electrical conductivity of prepared pellets appeared from an insulating (< 10−9 S/cm) wheat gluten control to semiconducting (0.2283 ± 0.0013 to 0.6498 ± 0.0039 S/cm) hybrid systems and highly conductive (40.79 ± 2.3 S/cm) carbon nanotube-rich composite pellet. These findings demonstrate that microstructure-guided processing enables tunable charge transport in biodegradable protein matrices. This work will help future studies to explore long-term stability, mechanical performance, and device-level integration for sustainable bioelectronic applications.

Polyvinylidene difluoride composite fibers with uniformly dispersed lead zirconate titanate (Pb (Zr0.52Ti0.48) O3) particles were synthesized via electrospinning technique. The fraction of electroactive β-crystalline phase within PVDF polymer matrix was enhanced upon incorporation of PZT particles from 65.7

The development of advanced, lightweight electromagnetic interference (EMI) shielding materials with exceptional stability and performance is top priority for the effective mitigation of electromagnetic pollution. Herein, we report a hierarchical composite architecture based on zeolitic imidazolate framework-11 (ZIF-11) and titanium carbide MXene (Ti3C2Tx) nanosheets with precise control over variable composite loadings (14 wt%, 16 wt%, and 18 wt%) within the mesoporous carbon foam scaffold. The resulting composite exhibits a three-dimensional conductive framework with enhanced surface area and optimized electrical conductivity achieved through structural and interfacial engineering that synergistically enhances EMI shielding effectiveness. The structural characteristics, phase purity, surface morphology, vibrational modes and thermal stability of the as-synthesized composite were systematically investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Among the three compositions investigated, the optimal composite with 18 wt% filler-impregnated carbon foam achieved an outstanding EMI shielding effectiveness of 64 dB in the X-band frequency range (8.2-12.4 GHz), primarily attributed to combined dielectric loss, interfacial polarization, and improved electrical conductivity. Thermogravimetric analysis further reveals enhanced thermal stability of the as-synthesized composite up to similar to 560 degrees C, highlighting the structural robustness of the system under operational conditions. These results demonstrate a scalable and rational design strategy for developing advanced EMI shielding materials, offering an augmented and robust solution for enhancing electromagnetic shielding properties for the next-generation miniaturized electronics and communication systems.

In this work, Sr-doped Ruddlesden–Popper nickelates, La2-ySryNiO4-δ (y = 0.25, 0.5, and 1.0), are investigated for microwave absorption applications. Tetragonal layered structures are confirmed by X-ray diffraction, while electron paramagnetic resonance and magnetic hysteresis measurements reveal that moderate Sr substitution induces weak ferromagnetic behavior, whereas higher Sr contents suppress magnetic ordering, leading to paramagnetic- or diamagnetic-like characteristics. Among the investigated compositions, the y = 0.25 sample exhibits the best impedance matching (|Zin/Z0| ≈ 1), delivering an ultralow RLmin of − 89 dB at a matching thickness of 0.9 mm and an effective absorption bandwidth of 2.1 GHz in the X-band. In contrast, higher Sr concentrations are associated with reduced dielectric loss and weaker absorption, likely due to changes in defect structure and charge-transport pathways. These results demonstrate that controlled Sr doping effectively tunes electromagnetic dissipation in layered nickelates, highlighting La2-ySryNiO4-δ as a promising candidate for microwave absorption applications.