Abstract This study reports the successful synthesis of two novel metal-organic frameworks (MOFs), Co-L MOF and Ni-L MOF, using a custom-designed Schiff base linker, 4-(((2E,3Z)-4-hydroxy-4-phenylbut-3-en-2-ylidene)amino)benzoic acid (LH). The frameworks were thoroughly characterized using a suite of techniques, including FTIR, XPS, PXRD, FESEM-EDX, BET, and TGA, which confirmed their porous structures, specific coordination geometries (square planar for Co(II) and octahedral for Ni(II)), and thermal stability. The antibacterial efficacy of both MOFs was evaluated against clinical strains of Escherichia coli and Staphylococcus aureus. Results demonstrated that both MOFs exhibited significant antibacterial activity, with Co-L MOF showing superior performance, as evidenced by larger inhibition zones (20 mm for both strains) and lower minimum inhibitory concentrations (MICs: 0.64 mg/ml for E. coli and 0.32 mg/ml for S. aureus). This enhanced activity is attributed to its geometry and higher surface-to-volume ratio, which facilitates better bacterial interactions. The proposed antibacterial mechanism involves the generation of reactive oxygen species (ROS) and electrostatic interactions, leading to damage to the bacterial cell membrane. These findings underscore the potential of Schiff base-derived MOFs as promising antibacterial agents.

Abstract Silk cocoons of the domesticated silkworm Bombyx mori exhibit exceptional mechanical performance, serving as natural protective casings evolved over millennia to resist environmental threats and predation. This review critically examines the relationship between the cocoon’s molecular composition, hierarchical architecture, and its multifunctional mechanical behaviour. We begin by reviewing the primary and secondary structures of silk proteins, particularly fibroin and sericin, and their contribution to β-sheet crystallinity and tensile strength. At larger length scales, the anisotropic, multilayered structure of the cocoon wall demonstrates a strategic gradation in porosity, fibre density, and mechanical stiffness from outer to inner layers, supporting a synergistic defence strategy. Mechanical tests reveal notable resistance to tensile, tearing, stabbing, and puncture loads, with measured values that at times, outperform synthetic polymers, foams, and textiles. Finite element simulations further elucidate the cocoon’s stress redistribution mechanisms under a range of loading scenarios. Drawing from these insights, this review identifies critical knowledge gaps, particularly in interfacial mechanics, environmental effects, and hierarchical modelling, and outlines promising directions for bioinspired material design. We find that the B. mori cocoon is a model of evolutionary optimization, and a blueprint for next-generation damage-tolerant structures.

Abstract Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is characterized by epidermal immune dysregulation, barrier dysfunction, and persistent inflammation. There is no cure for AD yet. Topical treatments often struggle with poor skin absorption, necessitating frequent applications and higher medication doses, which can lead to systemic side effects. In this study, we explore the use of nanotechnology-based topical delivery systems to enhance the therapeutic management of AD. Nanoparticles encapsulating anti-inflammatory drugs enable targeted delivery to the epidermis and upper dermis, where inflammatory processes are most active. This localized release at the site of immune cell infiltration leads to higher local drug concentrations, prolonged skin retention, and reduced systemic exposure. This approach offers several clinical benefits, including a faster therapeutic response, reduced dosing frequency, and improved overall efficacy. Drug delivery represents a promising strategy for optimizing topical AD treatment while minimizing adverse effects.

Abstract In the current work, a novel methodology based on the green approach has been carried out to prepare polymer composites with declined optical band gap. The extracted dye of black tea was used to create Mn2+ metal complexes. The XRD outcomes establish that Mn2+ complexes disrupt the hydrogen bonding between polyvinyl alcohol (PVA) chains. The FTIR results confirm the occurrence of interactions among the components of PVA composites. The UV–visible spectroscopy study was carried out to measure the fundamental optical and optoelectronic parameters, including absorption edge, refractive index (n), dielectric loss (εi), band gap energy (Eg), phase velocity, grouped velocity, sheet resistance (Rs), and thermal emissivity (εth) of the pure PVA and composite films. The results showed that the doped PVA exhibits a band gap of 1.62 eV. Furthermore, Tauc’s method was implemented to determine the possible types of electronic transitions. The ASF method was examined as an alternative to Tauc’s approach to determine the Eg values. Increasing in band tail from 0.269 to 0.362 eV indicates a remarkable presence of disorder phases in composite films. The W-D model was used to evaluate the oscillator energy E0. From Taucs model it was found that the optical band gap declines from 5.893 eV for pure PVA to 1.849 eV for PVA composites. The refractive index of PVA polymer was found to improve for PVA inserted with Mn-metal complexes. The results establish that polymer metal complexes are more efficient in increasing light-matter interactions.

Abstract This study investigates the electrochemical properties of manganese oxide (MnO2) and titanium nitride (TiN) incorporated with graphene nanoparticles (GN) synthesized from rice husk ash (RHA) for supercapacitor applications. The GN was varied while the mixture of manganese oxide and titanium nitride (with a ratio of 50 : 50) remained constant. XRD and SEM were used to examine the GN synthesized from RHA and MnO2-TiN/GN nanocomposites’ morphology. Cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy tests were employed to study the electrochemical behaviors of the fabricated nanocomposites. A 70 wt%MnO2-TiN/30 wt%GN nanocomposite exhibits significantly improved specific capacitance of approximately 318 Fg−1 at a scan rate of 5 mVs−1 using a three-electrode configuration, which amounts to about 224.3% increment compared to the MnO2-TiN. Also, a two-electrode configuration test was used to further analyze the electrochemical performance of 70 wt%MnO2-TiN/30 wt%GN nanocomposite by forming a symmetric device. An energy and power density of about 29.3 Wh kg−1 and 5250 Wkg−1, respectively, were calculated. The 70 wt%MnO2-TiN/30 wt%GN nanocomposite-based device demonstrated excellent capacitance retention of 78.7% after 2000 cycles. This work demonstrates the possible use of eco-friendly agro-waste-derived GN and explores its synergistic effects with MnO2-TiN in developing MnO2-TiN/GN nanocomposites for supercapacitor electrodes.

Abstract The electronic, structural, and optical properties of both pure and Cu-doped NiO have been examined using density functional theory (DFT) with the generalized gradient approximation (GGA) and the Hubbard correction potential (U). Modeling of supercells with Cu concentrations of 6.25% and 12.5% (Ni15CuO16 and Ni7CuO8), the results reveal significant modifications in the optoelectronic characteristics of NiO. The bandgap of pure NiO is 3.07 eV expressively dropped to 1.2 and 1.0 eV for the above mentioned doping levels respectively. The imaginary dielectric function, complex imaginary refractive index, optical conductivity, and energy loss were computed using NiO and Cu-doped NiO absorption coefficient spectra. The DFT approach results demonstrate the capability of Cu insertion on tuning all optical parameters of NiO. The reduction in the sharpness behavior of the NiO absorption spectra, the red shift in the absorption edge, and the observation of an additional absorption feature below the conduction band are evidences for the appearance of acceptor states near the valence band. The noticeable increase in optical absorption in the UV-visible and IR spectra suggests that Cu doped NiO materials suitable for photocatalysis, optoelectronics, and collecting solar energy.

Abstract These days, textile industries pose a more significant threat to surface water and groundwater sources directly or indirectly by discharging wastewater containing various dyes and organic pollutants to these water sources. The phase-junction-engineered heterogeneous photocatalysis carried out by visible light-driven semiconductor photocatalysts is opening a new window for the degradation of environmental organic pollutants. In this work, we have reported a one-step bottom-up hydrothermal synthesis of biphasic tungsten oxide (o/h-WO3) and performed a photodegradation experiment under visible light irradiation for the efficient degradation of organic pollutants such as Methylene blue (MB) and Methyl violet (MV), respectively. The X-ray diffraction, RAMAN, transmission electron microscopy and ultraviolet–Vis characterization techniques were used to investigate the structural, morphological and optical properties of the as-synthesized o/h-WO3. Moreover, the low calculated band gap (∼2.8 eV) and the anionic nature of o/h-WO3 suggest it as an efficient visible light-driven photocatalyst suitable for heterogeneous photocatalysis. The photodegradation experiment performed under visible light using o/h-WO3 photocatalyst showed better degradation efficiency of 71% and 89% for MB and MV, respectively, in 100 min. The dyes followed first-order kinetics, and their kinetic rate constants were calculated using the Langmuir–Hinshelwood model. Furthermore, the recyclability study of the photocatalyst was also performed and discussed the underlying mechanism for the photodegradation of the organic dyes.

Abstract In the last several decades, textile-reinforced composites have emerged as a unique class of materials offering intricate features, reduced fabrication costs, introduced multiaxial reinforcement, and enhanced damaged tolerance. Despite these benefits, textile-reinforced composites face challenges as predicting their performance often relies on heuristics and past experiences without gaining insights into the underlying structure of the textile material and its constituents. This tutorial-based mini-review aims to delve into the fundamentals of textile architecture in the context of textile-reinforced composites and provide an overview of their significant physical and structural features that influence the performance characteristics of textile-reinforced composites.

Abstract We study theoretically fundamental Coulomb-correlated complexes: neutral and charged excitons, also known as trions, in transition metal dichalcogenides monolayers. We focus on the situation where one of the electrons occupies an excited, high-lying, conduction band characterized by a negative effective mass. We develop the theory of such high-lying excitons and trions with negative effective mass and demonstrate the key role of the non-parabolicity of the high-lying conduction band dispersion in the formation of the bound exciton and trion states. We present simple, accurate and physically justified trial wavefunctions for calculating the binding energies of Coulomb-bound complexes and compare the results of variational calculations with those of a fully numerical approach. Within the developed model, we discuss recent experimental results on the observation of high-lying negative effective mass trions.

Abstract The Density Functional Theory (DFT) and time-dependent-DFT method with Becke’s three-parameter Lee-Yang–Parr functional approach at a basis set of 6-311G was used to analyze the ground state and excited state properties of newly designed donor–acceptor–donor (D–A–D′) donor molecules based on triphenylamine and carbazole as donor units and benzothiadiazole and its derivatives as acceptor units to make a total of nine potential monomers. The energies associated with highest occupied molecular orbital, lowest occupied molecular orbital, energy gap (Eg), electron excitation (Eopt), exciton binding (Eb) and open-circuit voltage (Voc) were calculated, and the simulated absorption spectra in both gas and chlorobenzene solvent were plotted. The outcomes of replacing the acceptor building unit and substituting the donor units to tailor the optoelectronic properties of the designed monomers were discussed. The monomer molecules A7, A8 and A9 are suitable for [6,6]-phenyl-C61-butyric acid methyl ester because of their small Eg, Eopt, Eb and, more importantly, large Voc values. Suggesting changing the acceptor unit and substituting the donor units of the D–A–D′ seem to be an excellent approach to tailoring the optoelectronic properties of the molecules.