As a possible electrocatalyst, a two-dimensional heterostructure made up of a metal that conducts electricity very well and a metal oxide that conducts electricity has been discovered. In this investigation, we utilized co-precipitation strategy as a simple method to synthesize novel two-dimensional nanosheets of cobalt-doped zinc oxide (Co@ZnO). Through a post-annealing process, the cobalt in the hybrid material is stabilized in the + 2 oxidation state, facilitating the transformation of the precursor into crystalline cobalt-substituted zinc oxide nanosheets while preserving the original morphology. Structural and morphological analyses which revealed the characteristics of the synthesized nanosheets. The electrochemical experiments showed that Co doped ZnO (Co@ZnO) nanosheets, with an optimal doping concentration of 2 wt%, demonstrated outstanding electrocatalytic performance for the ORR in a alkaline medium (0.1 mM KOH), exhibiting an onset potential of 0.88 V and a nearly four-electron mechanism. The Co@ZnO nanosheets displayed superior electrochemical stability compared to pristine ZnO for the ORR. Compared to commercially available RuO2 catalysts, the Co@ZnO catalyst exhibited significant activity in the OER throughout the experiment. It’s likely that the defect sites and porous structure of Co@ZnO nanosheets worked together to make the catalyst so effective in both OER and ORR.

The rise of multidrug-resistant bacterial strains has created an urgent need for alternative antimicrobial agents. In this study, we report the green synthesis of mesoporous Ag@ZnTiO_₃ nanocomposites using ethanolic leaf extract of the Gaga plant. The synthesized materials were characterized for structural and morphological features and evaluated for antibacterial activity against both Gram-positive and Gram-negative bacteria. The antibacterial performance of the mesoporous Ag@ZnTiO₃ nanocomposites was evaluated against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria using disk diffusion and minimum inhibitory concentration (MIC) methods. Mechanistic insights revealed that the antibacterial mechanism involves reactive oxygen species (ROS) mediated oxidative stress, membrane disruption, and inhibition of cellular processes, leading to bacterial cell death. Mesoporous Ag@ZnTiO₃ nanocomposites demonstrate excellent antibacterial efficacy and stability, making them a promising candidate for next-generation antimicrobial agents in medical and environmental applications. In addition, a One-way ANOVA study revealed that the plant-synthesized nanocomposite exhibited a significantly greater antibacterial effect on the Gram-negative bacterial strain compared to the Gram-positive strain. The p-values less than 0.05 (p < 0.05) indicate the statistical significance of the model terms. Further studies on scalability and long-term safety are recommended to pave the way for practical implementations.

The field of separation sciences is experiencing a profound transformation driven by sustainability imperatives. The chapter explores pioneering sustainable separation processes and technologies poised to revolutionize chemical and industrial separations. Green solvents and extraction techniques reduce environmental footprints, while membrane separation technologies offer energy-efficient and selective solutions. Principles of waste minimization and circular economy promote reduced waste generation and recycling, conserving valuable resources. Energy-efficient separation processes and integration of renewable energy sources further minimize carbon footprints. Nanotechnology is a game-changer in separation sciences, providing solutions through functionalized nanoparticles, nanomembranes, and targeted drug delivery systems that improve selectivity, precision, and resource efficiency while reducing energy consumption and environmental impact. Techniques for process intensification, such as reactive distillation and membrane reactors, maximize resource utilization. These advancements, taken together, create the foundation for a more sustainable and ecologically conscious future for separation sciences.

Water purification and recycling technologies are explored universally to provide hygienic resources to the upcoming generation. Lack of appropriate waste-management measures led to a rapid increase in water pollution, and to prevent this situation fast, inexpensive and precise water-purification approaches must be taken. The development of nanomaterials as membranes or adsorbents of hazardous chemicals, heavy metals, or dyes from water have been challenging. The effective nanostructured nanomaterials have garnered research interests in this dome. After successful synthesis of different dimensional materials, 1D nanoribbons came into eminence due to their unique features. In this chapter, the basics of nanoribbon-based nanomaterials and its various configuration applied in water treatment will be discussed. An extensive survey will be done to summarize different processes for water treatment and the role of nanoribbons in these processes. Thus, water recycling via nanoribbon-based nanomaterials or membranes can be an excellent ecological approach for safe and pure water sources. Additionally, major challenges that limit the practical application of the membranes, nanomaterials in absorption, or photocatalytic degradation in water recycling will be highlighted.

The present article portrayed on the killing kinetic of human pathogenic bacteria using bioinspired mesoporous CuAl2O4 nanocomposites (NCs). The NCs was fabricated using leaf extract of medicinal plant Catharanthus roseus (CR) as a green reducer and stabilizer. As bio-fabricated material was calcined at 800 °C and characterized by several analytical techniques like X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV-DRS), Energy Dispersive X-Ray Spectroscopy (EDS), X-Ray Photoelectron Spectroscopy (XPS), Raman, Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) to authenticate its structure, phase, chemical bonding, chemical state, size and morphology behaviors. XRD and TEM revealed a reduced crystallite and nanoscale sizes of biosynthesized NCs. Moreover, XRD study exposed a cubic-structure of material, while transmission electron microscopy rendered an average particles size in range 10–15 nm. However, BET profile advocates a mesoporous nature of the particles. An effective biological molecular docking modulation assessed by substituting natural inhibitor by bioinspired NCs, while the protein PDB ID 4Z8D FabH as a receptor site for the present investigation. After assessment of molecular docking examination, the antibacterial activity of bioinspired NCs were performed against Staphylococcus aureus, Bacillus subtillis, Klebsiella pneumoniae and Escherichia coli using agar-well method. The broth culture method was employed on different pathogenic strains by kinetic growth assays and colony forming unit.

In this communication, we have measured the densities and ultrasonic velocities for the binary mixtures of (Ortho Methoxy Aniline + Benzene) and (N-Methyl Aniline + Benzene) over the entire volume fraction range 0.1-1 at303K- 318K and at ambient pressure. The experimentally obtained data were used to evaluate different derived parameters such as adiabatic compressibility, Intermolecular free length, acoustic impedance, molar volume, molar sound velocity, molar compressibility, relative association, excess volume, and excess adiabatic compressibility. The outcome of all derived parameters is well explained by intermolecular interaction studies present in the non-aqueous binary organic liquid mixture. Moreover, the densities and ultrasonic velocities of the binary mixtures were used to compare different correlating relations. The negative values of the excess volume and excess adiabatic compressibility with volume fraction and temperature confirm the presence of strong interaction through dipole-dipole and dipole-induced dipole interactions in the studied systems.

Microwave-assisted synthesis is a powerful tool in organic chemistry, providing a rapid and efficient method for the synthesis of bioactive heterocycles. The application of microwaves significantly reduces reaction times and increases percentage yields with high purity of the final product. To make the synthetic protocol greener, the application of the magnetic nanocatalyst is a rapidly growing area of interest nowadays. Magnetic nanocatalyst, with its unique features like magnetic separable facile recovery from the reaction media heterogeneously, makes the overall synthetic strategy cleaner, faster, and cost-effective. Aiming this, in the present review, we will focus on the infusion of Magnetic nanocatalyst to microwave-assisted synthesis of various classes of azaheterocyclic compounds, including pyridines, pyrimidines, quinolines, and benzimidazoles. The synthetic methodologies involved in the preparation of these heterocycles are highlighted, along with their biological activities. Furthermore, in this review, the most recent and advanced strategies to incorporate nanocatalysts in the microwave-assisted synthesis of natural products containing azaheterocyclic moieties in drug discovery programs are elucidated in detail, along with the incoming future scope and challenges.

The present article reports the synthesis of thoria nanoparticles (ThO2 NPs) via sol-gel process and examines the effect of calcination temperature of ThO2 on the morphology and photocatalytic degradation of indigo carmine (IC) and methylene blue (MB) under visible-light. As-synthesized white crystals of ThO2 were subjected to calcination at different temperatures, viz. 700 °C (TH-700), 800 °C (TH-800), and 900 °C (TH-900). The effect of calcination temperature on the structural, morphological, thermal, surface area-porosity, and optical properties of ThO2 NPs were investigated by diverse analytical techniques. XRD patterns show the cubic-space group Fm-3m (225) with parameter a = 5.597 Å and reveals crystallite sizes increased with calcination temperature. The bandgap energy was found to be 1.85 eV, 2.33 eV, and 2.71 eV for TH-700, TH-800, and TH-900 NPs, respectively, calculated by Kubelka-Munk (KM) plot. SEM and TEM unveil that the sample TH-700 calcined at a low temperature of 700 °C yields assembled nanosheets, while at higher temperatures, i.e., 800 °C (TH-800) and 900 °C (TH-900), produces agglomerated nanomaterials. Further, TH-700 sample exhibits enhanced photocatalytic degradation within 120 min for both IC and MB dye than TH-800 and TH-900 counterparts. Among the dyes, IC shows improved photocatalytic efficiency than MB for TH-700, owing to the increased optical absorption and improved separation of photogenerated charge carriers. The reusability study of TH-700 reveals that the catalysts were stable up to four successive cycles with no drastic changes in photocatalytic efficiency. Also, systematic photodisintegration of IC was investigated by Liquid chromatography–mass spectrometry (LC–MS).