Sanjeev Kumar

ZnO nanoparticles (NPs) were synthesized via a green route using citrus waste (citrus limon peel) extract and subsequently incorporated into a typical nematic liquid crystal (NLC), 4-cyano-4′-pentylbiphenyl (5CB) to investigate their influence on dielectric and electro-optic behaviour. Structural and optical characterization confirmed crystalline hexagonal wurtzite structure with an average crystallite size of ~51.9 nm, an optical band gap of 2.68 eV, moderate colloidal stability and with nanoscale dimensions, enabling effective interfacial interaction with NLC host. Further, these green-synthesised ZnO NPs were dispersed in 5CB at concentrations of 0.05, 0.1, 0.25, and 0.5 wt.%. Incorporation of ZnO NPs into the 5CB matrix showed a systematic increase in its clearing temperature (TN-I) indicating enhanced orientational ordering. Dielectric measurements revealed the significant improvement in dielectric permittivity and dielectric anisotropy, attributed to interfacial polarization and strengthened dipolar interactions. Electro-optic analysis demonstrated that NPs concentration critically governs performance of the composite. The 0.1 wt.% ZnO-LC composite exhibited the optimum dielectric and electro-optical response, showing enhanced birefringence, improved contrast ratio, and efficient switching dynamics without significant disruption of nematic order. However, the higher concentrations of NPs resulted into partial aggregation and reduced electro-optic efficiency. Overall, these results establish that engineering interfacial interactions in LC nanocomposites offer a powerful route to tailor dielectric and electro-optic functionality and identifying optimum NPs concentration as the key design parameter for next-generation, eco-friendly, energy efficient LC-based photonic and display technologies.

Hypothesis: Modulating the aqueous hydrolysis environment and phytochemical coordination can deterministically engineer the solid-liquid interface of biogenic titanium dioxide to enhance reactive oxygen species generation. Experiments: A dilution-controlled phyto-hydrothermal strategy using Citrus cavaleriei extract was developed to synthesize refined anatase nanoparticles. Interfacial descriptors were characterized through multi-spectroscopic profiling, nitrogen adsorption, and electrokinetic measurements. Functional efficacy was evaluated via photocatalytic antibiotic degradation and cytotoxicity assessments in human breast cancer cells. Findings: Systematic dilution modulated nucleation kinetics, yielding 9-nanometer anatase with an exceptionally high accessible surface area of 126.35 square meters per gram. Lipid-rich ligands regulated crystal growth, establishing an amphoteric interface with a point of zero charge at 6.61. The optimized interface drove 92% tetracycline mineralization within 80 minutes and triggered BAX/BCL-2-linked apoptosis-associated progression with CASP-7 upregulation in malignant cells. This work establishes a robust descriptor-performance framework for the rational design of high-performance biogenic interfaces.

In this work, a green route to enhance nematic liquid crystal performance is demonstrated by incorporating plant-derived copper oxide nanorods (CuO NRs) into 4-pentyl-4′-cyanobiphenyl (5CB). CuO NRs were synthesized via a clove-extract-assisted hydrothermal method and confirmed to be crystalline and well-defined in morphology. Even at low concentrations (0.05–0.3 wt.%), the NRs induce pronounced, concentration-dependent changes in dielectric and electro-optical behavior. Strengthened NR-liquid crystal interactions enhance orientational stability, which is reflected in modified dielectric anisotropy, increased activation energy, elevated nematic-isotropic transition temperature, and improved birefringence. Simulatneous reductions in threshold voltage, elastic constant, and rotational viscosity lead to faster switching and improved electro-optic efficiency. At higher concentration (0.3%), the appearance of volatile memory behavior suggests nanorod-mediated stabilization of field-induced alignment. These results establish that green-synthesized CuO nanorods are active functional modifiers which may enable sustainable and high-performance liquid crystal composites for advanced photonic and display applications.

2D MXenes have emerged as a cutting-edge family of materials for next-generation supercapacitors, distinguished by their metallic conductivity, adaptive surface chemistry, and precisely tunable layered architecture. These materials have emerged as promising materials for energy storage in supercapacitors; however, challenges such as restacking and structural degradation have motivated the development of composites, which can synergistically enhance electrochemical performance and stability. This review elucidates the charge storage mechanisms in MXene-based composites, including the formation of electric double layers, pseudocapacitance, and ion intercalation. It also highlights the charge storage mechanisms involved in MXene-based composites, mainly including carbon nanostructures, inorganic materials, and organic matrices. MXene–carbon hybrids with graphene, carbon nanotubes (CNTs), carbon nanodots enhance ion/electron transport and prevent restacking; MXene–inorganic hybrids with metal oxides, metal-organic frameworks (MOFs), etc., provide abundant redox sites and structural stability; and MXene–organic composites with polymers or cellulose offer mechanical flexibility, processability, and environmental compatibility while maintaining excellent electrical performance. The review also discusses current challenges such as oxidation, aggregation, and interface instability, proposing strategies such as interfacial engineering, surface functionalization, and 3D structural design. By bridging compositional innovation with electrochemical insight, this article presents a holistic framework for the development of next-generation MXene-based supercapacitors that combine high energy density, long-term durability, and mechanical adaptability.

The charge-state distribution (CSD) of the projectile ions through solid targets in the intermediate energy range ( 1 MeV / u < E < 4 MeV / u ) has a major impact on the collision of the ion atom and accelerator physics. We explore the mean charge states taken from the empirical formula [G. Schiwietz , Femtosecond dynamics–snapshots of the early ion-track evolution, ] are only good for projectile ions with Z 1 ≤ 16 . To solve this issue, we develop a model in which instead of a single formula, if we employ four formulas, the comparative picture between experimental and empirical data becomes impressive. Furthermore, the CSDs obatained using the mean charge state and the Gaussian distribution function having distribution width as given by Novikov and Teplove [Methods of estimation of equilibrium charge distribution of ions in solid and gaseous media, , 1286 (2014)] show good agreement with the experimentally measured CSDs for the entire range of projectile ions. We believe that accurate CSDs will be highly useful for both ion-atom collision and accelerator physics.

Zinc oxide (ZnO)-reinforced polymer composites have emerged as a promising class of multifunctional materials with significant potential for advanced additive manufacturing, particularly 3D printing. This review systematically explores the synthesis, microstructural tailoring, and performance optimization of ZnO-polymer composites, focusing on structure-property relationships critical for load-bearing and functional applications. The integration of ZnO nanostructures, including nanoparticles, nanorods, and nanosheets, into thermoplastic and thermoset matrices is examined in terms of enhancing mechanical strength, electrical conductivity, piezoelectric response, and thermal stability. Particular attention is given to transition metal-doped ZnO systems, which introduce tuneable optoelectronic and dielectric properties beneficial for next-generation printed devices. Recent advancements in 3D printing techniques, such as fused deposition modeling and selective laser sintering, are reviewed for their role in enabling precise control over composite morphology and interfacial bonding. Critical challenges, including nanoparticle dispersion, matrix-filler compatibility, and defect minimization during the printing process, are discussed alongside emerging trends in 4D printing and smart composite design. This review offers a comprehensive perspective on how ZnO-polymer composites are advancing printed architectures’ functionality and structural integrity, paving the way for innovations in flexible electronics, biomedical scaffolds, and energy devices.

The online version contains supplementary material available at 10.1038/s41598-025-24674-5.

In this study, we report the green synthesis of multifunctional nanocomposite hydrogels by incorporating silver nanoparticles (Ag NPs) into gum acacia (GA)‐grafted poly(methacrylic acid) (GA‐g‐poly(MAA)) and poly(methacrylic acid‐aniline) (GA‐g‐poly(MAA‐ANI)) matrices using microwave irradiation. The synthesized nanocomposites' structural, morphological, and thermal properties were characterized using XRD, FTIR, FESEM, and TGA analyses, confirming the uniform dispersion of Ag NPs. The Ag NP content in the hydrogels was 0.17 wt% for GA‐g‐poly(MAA)/Ag and 0.11 wt% for GA‐g‐poly(MAA‐Ag‐ANI). They enhanced thermal stability up to 450°C. Antibacterial and antifungal activity tests demonstrated significant efficacy, with inhibition zones of 4 mm for Staphylococcus aureus , 3 mm for Escherichia coli , and 4 mm for Candida albicans . Minimum inhibitory concentration (MIC) values were as low as 0.5 μg/mL against C. albicans . The hydrogels achieved 92% methylene blue (MB) removal from a 50‐ppm solution using 2 g of hydrogel in 390 min, with an adsorption capacity of 45 mg/g. These results highlight these biocompatible, eco‐friendly nanocomposites' exceptional antimicrobial and dye adsorption capacity, presenting them as promising candidates for antimicrobial therapies and environmental remediation solutions. These results demonstrate the potential of nanocomposites for advanced wound dressings and efficient water treatment systems.