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Potential health, environmental implication of microplastics: A review on its detection
Microplastic contamination of terrestrial and aquatic environment has gained immense research attention due to their potential ecotoxicity and biomagnification property when enterer into food chain. Heterogenous nature of microplastics coupled with their ability to combine with other emerging pollutants have increased the severity of this crisis. Existing detection methods often fails to accurately quantify the amount of microplastic components present in environmental and biological samples. Thus, a great deal of research gap always exists in our current understanding about microplastics including the limitations in screening, detection and mitigation. This review work presents a comprehensive out look on the impact of microplastics on both terrestrial and aquatic environment. Furthermore, an in-depth discussion on various microplastic detection techniques recently used for microplastic quantification along with their significance and limitations is summarised in this review. The review also elaborates various physical, chemical and biological methods used for the mitigation of microplastics from environmental samples. 2024 Elsevier B.V. -
Ternary composite of unzipped multiwalled carbon nanotubes (curved graphenes) for next-generation capatteries
Polyaniline (PANI) and Nickel ferrite (NiFe2O4) based hybrid materials have garnered significant interest in energy storage applications because of their exceptional electrical conductivity, redox properties, and structural stability. In this study, a hybrid ternary composite combining UzMWCNT with NiFe2O4 and PANI (UzMWCNT/NiFe2O4/PANI) is successfully synthesized using a two-step synthesis method involving hydrothermal and in-situ polymerization, as an efficient electrode material for supercapacitor application. The crystalline structure, functional groups, and surface morphology of the synthesized composite materials were analyzed through X-ray diffraction studies (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The electrochemical performance was evaluated utilizing cyclic voltammetry (CV), galvanostatic chargedischarge (GCD), and electrochemical impedance spectroscopy (EIS). The interaction between the various components and the unique composition structure yields a specific capacitance of 1022 F g?1 at 1 A g?1, with a capacitance retention of 84 % after 2000 GCD cycles. The synthesized ternary hybrid composite maximizes the accessibility of multiple active sites while reinforcing structural stability, enhancing its energy storage performance. The research unveils the compelling advantages of the UzMWCNT/NiFe2O4/PANI ternary composite, positioning it as a cutting-edge candidate for next-generation energy storage devices. 2025 Elsevier Inc. -
Unveiling virtual interactive marketplaces: Shopping motivations in the Metaverse through the lens of uses and gratifications theory
The emergence of Metaverse has transformed the consumer shopping experience. This novel e-commerce platform offers a fresh approach to shopping, with Generation Z primarily exploring this innovative technology. Our research examines shopping within the Metaverse by developing a model based on the Uses and Gratifications Theory and Metaverse-related factors. A total of 1220 Gen Z consumers were surveyed, and data was collected using a structured questionnaire. Further, analysis of collected data was done using PLS-SEM. The results reveal that information seeking, perceived enjoyment, escapism, social interaction, sense of immersion, and personalization influence the shopping intention in the Metaverse, and perceived risk negatively influences the shopping intention of consumers. Further, shopping intention influences the potential use of Metaverse for shopping, and this relationship is moderated by technological innovativeness. This investigation into the adoption of the Metaverse for retail purposes augments the current Metaverse research and enhances the uses and gratifications theory within the Metaverse domain. Metaverse e-commerce professionals, including managers and developers, can acquire valuable perspectives on consumer shopping tendencies in the Metaverse from this study. 2025 The Author(s) -
A new perspective on the genesis of the 2019/2020 Australian bushfire and its atmospheric radiative impacts
Extensive investigations of the genesis and atmospheric radiative impacts of the Australian bushfires of August 2019 to January 2020 (also known as the black summer event) have been carried out using in-situ, multi-satellite, and reanalysis data. We present the observational evidence for the role of total water storage in the initiation of this event. A strong correlation was found between the depletion of the total water storage (sum of surface and sub-surface water storage) caused by the hydrological drought and the burnt area in southeast Australia. Notably, a decadal low of Liquid Water Equivalent Thickness (LWET) going below ?5 cm in December 2019 strongly suggests the crucial role of hydrological drought in the genesis of the black summer event. The hydrological drought provided favorable conditions for intense fire activity during the black summer event and increased the aerosol loading across Australia. The assimilated Aerosol Optical Depth revealed that the impact of the black summer event on the aerosol loading is higher than previously reported. The amplified aerosol backscattering, coupled with the increased surface albedo due to the prevailing drought, led to a significant surge in outgoing shortwave flux and contributed to regional cooling. Along with the increased aerosol loading, it has also been observed that the co-emitted carbon monoxide enhanced the ozone production at 850 hPa, further degrading the air quality. These findings will offer crucial insights for predicting extreme bushfire events and their mitigation policies. 2025 Elsevier Ltd -
Impact of hot rolling on the mechanical characteristics and microstructure of copper-based metal matrix composites reinforced with titanium carbide
Copper-based metal matrix composites reinforced with varying weight percentages (0, 2, 5, 7, and 10 wt%) of powdered titanium carbide (TiC) particles were successfully fabricated using stir casting, followed by hot rolling as a secondary processing route to enhance their mechanical performance. The microstructural evolution, phase characteristics, and mechanical behaviour of both as-cast and hot-rolled composites were systematically studied. Microstructural examination revealed a dendritic grain structure with non-uniform grain size distribution in as-cast composites, whereas hot-rolled composites exhibited a refined lath-shaped grain structure with uniform TiC particle distribution, attributed to the plastic deformation induced during rolling. XRD analysis confirmed the presence of high-intensity copper matrix peaks in hot-rolled composites and relatively stronger TiC peaks in as-cast composites due to the fragmentation of coarse reinforcement particles during rolling. Mechanical testing demonstrated that hot rolling significantly enhanced both hardness and tensile strength compared to the as-cast condition. The Brinell hardness of the hot-rolled Cu-10 wt% TiC composite reached 59.54 BHN, representing a 42.1% improvement over as-cast pure copper (41.9 BHN). Similarly, the ultimate tensile strength (UTS) of the hot-rolled Cu-10 wt% TiC composite achieved 182.5 MPa, corresponding to a 50.3% improvement over as-cast pure copper (121.4 MPa). However, ductility decreased progressively with increasing TiC content and hot rolling, from 71.56% in as-cast pure copper to 48.69% in hot-rolled Cu-10 wt% TiC, owing to strain hardening effects and grain boundary restriction by TiC particles. The optimal combined strength-ductility balance, assessed through the strain hardening parameter (UTS % elongation), was achieved at 5 wt% TiC reinforcement in both as-cast and hot-rolled conditions. Fractographic analysis revealed a progressive transition from ductile dimple fracture to mixed-mode and predominantly brittle fracture with increasing TiC content, consistent with the observed mechanical trends. 2026 The Authors. -
Zinc gallate nanoparticles: A multifunctional material for optoelectronic and optical limiting applications
Wide-bandgap spinel oxides have attracted increasing attention due to their structural stability and multifunctional properties, yet the nonlinear optical and optical limiting behaviour of zinc gallate (ZnGa?O?) remains largely unexplored. To address this gap, ZnGa?O? nanoparticles were synthesised using a hydrothermal method at different pH levels, with X-ray diffraction (XRD) confirming a phase-pure cubic spinel structure at pH = 10. Rietveld refinement further validated the crystal structure and was visualised using VESTA software. FTIR confirmed the presence of characteristic metaloxygen bonds. FESEM revealed an agglomerated nanoparticle morphology. TEM verified the particle structure, and EDAX confirmed elemental composition, collectively supporting the cubic structure. XPS validated the oxidation states of Zn? and Ga ?. Optical characterisation using photoluminescence and diffuse reflectance spectroscopy confirmed the wide bandgap nature of the material. Strong blue emission under UV excitation demonstrated the photoluminescent behaviour. DC conductivity measurements were conducted to evaluate the electrical transport behaviour of the synthesised material. The third-order nonlinear optical (NLO) properties were systematically investigated using open- and closed-aperture Z-scan techniques under continuous-wave and nanosecond pulsed laser excitation. The material exhibited reverse saturable absorption, a negative nonlinear refractive index, and a large third-order susceptibility, along with efficient optical limiting behaviour under pulsed excitation. These results demonstrate that hydrothermally synthesised ZnGa?O? nanoparticles possess strong third-order nonlinearity and effective optical limiting performance, establishing zinc gallate as a promising spinel oxide for laser protection and advanced photonic applications. 2026 Elsevier B.V. -
Transparent Cu-Pd decorated MoS2@functionalized carbon nanofiber composite counter electrodes: Efficient bifacial dye-sensitized solar cell
This research demonstrates a facile method for implementing bimetallic Cu-Pd-doped MoS2/Carbon fiber composites as a transparent counter electrode for bifacial dye-sensitised solar cell (DSSC) applications. The inert properties of the basal plane significantly limit the catalytic capabilities of MoS2. This limitation is alleviated through the incorporation of carbon fibers, owing to their excellent conductivity, catalytic activity, and stable structure. Cu and Pd nanoparticles were incorporated into MoS2, carbon fibers and a mixed MoS2/carbon fibers matrix via a one-step hydrothermal method. The structural, morphological, and catalytic properties were systematically investigated through microscopic studies, Cyclic Voltammetry, and Tafel analysis. Electrochemical Impedance Spectroscopy recorded charge transfer resistance RCT values for CuPdCNF, CuPdMS, and CuPdMSCNF are 16.50, 10.62, and 7.5 ?, respectively, attributed to the addition of metals that can alter both the geometric and electronic structures on the metal surface, which are closely associated with their catalytic efficiency. This approach has led to a significant enhancement in both short-circuit current density and overall efficiency with respect to bare MoS2 and Pt. The cells exhibited current densities of 16.00 mA/cm, 16.19 mA/cm, and 16.71 mA/cm, with corresponding efficiencies of 7.03 %, 6.86 %, and 7.77 %, respectively, under front illumination for CuPd-CNF, CuPd-MS, and CuPdMSCNF. Additionally, the introduction of these bimetallic NPs within the carbon and MoS2 matrix further increases the active site for catalytic reduction. The combination of significant efficiency and rear illumination adaptability underscores the strong potential for practical use in bifacial solar cell configurations. 2026 Elsevier B.V. -
Flexible Ni-Zn aqueous battery based on Ni?S?/NiO composite cathode with high energy-density and durability
The development of high-performance flexible aqueous zinc batteries requires innovative manufacturing protocols, suitable electrode composition and large area, three-dimensional architecture that results in exceptional electrochemical properties even under mechanical deformation. This work presents a unique approach for synthesizing flexible alkaline Ni-Zn batteries utilizing Ni?S?/NiO composite cathode over highly flexible and durable micro/nano-textured stainless steel mesh with excellent electrochemical performance. The binder-free composite cathode was developed through nickel electrodeposition followed by hydrothermal processing to create Ni?S?/NiO composite nanowires. The innovative anode design employs zinc composite coated on a pressed copper foam, significantly outperforming conventional zinc foil configuration. The Ni3S2/NiO/SSE composite cathode delivers an impressive specific capacity of 452 mAh/g, demonstrating excellent electrochemical properties at the electrode level. This advanced electrode architecture also enables the assembled device to showcase outstanding performance, delivering 316 mAh/g specific capacity at 1 A/g, a remarkable energy density of 553 Wh/kg, and exceptional power density of 11.19 kW/kg, substantially exceeding most reported aqueous zinc battery systems. Further, the device maintains stable electrochemical performance across various bending conditions, demonstrating superior mechanical flexibility essential for the advanced electronics and flexible energy storage applications. 2025 Elsevier B.V. -
Tailored cobaltnickel phospho-boride from metalorganic frameworks as high-performance catalyst for NaBH4 dehydrogenation
Achieving efficient hydrogen generation (HGR) via the hydrolysis of sodium borohydride (NaBH4) remains a key challenge in developing cost-effective and high-performance catalytic systems for chemical hydrogen storage. In this study, we present a novel bimetallic phospho-boride-modified metal-organic framework catalyst (CoNi-PB-MOF), synthesized through a two-step process involving hydrothermal assembly followed by chemical reduction. The co-incorporation of phosphorus and boron into the bimetallic Co-Ni MOF facilitates the formation of 2D MOF-derived nanoplates embedded with Co3O4 nanoparticles doped with P and B. This hybrid structure features a high surface area, abundant active sites, and reduced charge-transfer resistance, enabling superior catalytic activity. The CoNi-PB-MOF catalyst achieves an impressive HGR of 7.33 L/min/g from NaBH4 hydrolysis, outperforming its monometallic counterparts. Comprehensive physicochemical and electrochemical analyses confirm the synergistic roles of Co, Ni, P, and B in enhancing catalytic performance, while preserving the porous MOF morphology post-modification. The CoNi-PB-MOF catalyst exhibits a low activation energy of 25.6 kJ/mol, along with excellent thermal stability and cyclic durability under harsh conditions. Kinetic studies reveal a zero-order reaction with respect to NaBH4 concentration, attributed to efficient mass transport and surface diffusion on the optimized catalyst surface. 2025 Elsevier B.V. -
Polyoxometalate/?-Fe2O3/polyaniline composite: Tailored approaches for high-performance supercapacitors
The need for portable, high-performance electronics that have high power or energy density has increased significantly in recent years. In this work, a composite material was coated on stainless steel that consists of polyoxometalate (POM)/?-Fe2O3/polyaniline (PANI) as an electrode material for a symmetric supercapacitor. ?-Fe2O3 was prepared using starch as a template while PANI was electrodeposited. The physical and chemical characteristics of the modified electrodes were investigated via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge[sbnd]discharge (GCD) experiments. In 1 M H2SO4, the composite had a specific capacitance of 528 F/g at a current density of 0.2 A/g. In addition, the composite exhibited a high energy density of 73.4 Wh kg?1 at a high-power density of 7.14 kW kg?1 and 91.62 % capacity retention after 10 cycles. The results show that POM/?-Fe2O3/PANI is a promising composite electrode for use as a supercapacitor electrode material. 2024 The Authors -
Exploring the nexus of climate change and vector-borne disease transmission
Climate change is a critical global challenge that significantly impacts the redistribution of malaria endemicity worldwide. While efforts have been made to model malaria transmission using climatic factors, relying solely on these factors can lead to discrepancies and ineffective decision-making. To address this, we used the VECTRI modela dynamic framework developed by the International Center for Theoretical Physics (ICTP) that integrates both climatic and entomological factorsto map malaria risk for India and project its potential future under the SSP370 warming scenario. Our findings indicate that the length of malaria transmission is expected to increase across India by the end of this century. The shift of malaria endemicity to further north and also into highland areas could increase the at-risk population due to lower immunity in these regions. Therefore, integrated climate and entomological modeling is essential for effectively anticipating malaria transmission risks and enhancing public health responses. 2025 -
DMRD-Net: Dual modality retinal diagnostic network with few shot episodic learning and XAI interpretability
Early diagnosis of retinal pathologies is critical for preventing irreversible blindness, particularly in rare conditions with limited labeled medical data. Traditional diagnostics employ a single imaging modality, limiting the identification of heterogeneous anomalies in the retina. DMRD-Net, a diagnostic system is presented that integrates spectral-domain optical coherence tomography with fundus photographs, utilizing two parallel branches of a neural network, that is EfficientNet-B0 encoders and few-shot episodic meta-learning module based on Prototypical Networks, that merge their outputs to enhance the precision of diagnosis. Supervised learning methodologies are employed to identify common retinal diseases, followed by the application of meta-learning technique, referred to as Prototypical Networks, to aggregate a limited set of data for the study of rare diseases. To support clinical confidence and improve transparency, explainable artificial intelligence is utilized to facilitate decision-making by models. It facilitated the evaluation of performance on both common and rare retinal disorders. The system achieved over 96% episodic accuracy in diagnosing rare conditions, including Macular Hole, Retinitis Pigmentosa, and Stargardt Disease, in Central Serous Chorioretinopathy. The overall classification accuracy for common diseases was 96.5%. Overall, DMRD-Net is a unified, data-efficient, and interpretable multimodal diagnostic system that works well for both common and rare retinal disorders. 2026 The Author(s) -
Green synthesis of Fe-doped manganese oxide nanoparticles: enhanced their antibacterial and anticancer properties assessed by biological analysis
Eco-friendly synthesis methods are becoming increasingly important as a sustainable way to produce nanoparticles, thereby improving their potential for biomedical applications. The nanoparticles have a small size, a high surface area-to-volume ratio, and the ability to be functionalized with targeting ligands, making them ideal for drug delivery, imaging, and diagnostic purposes. In anticancer therapies, nanoparticles can enhance treatment efficacy by improving drug solubility, enabling controlled release, and selectively targeting cancer cells, thereby minimizing side effects on healthy cells. In the present work, the green engineering of manganese oxide (GEMn2O3) and iron-doped manganese oxide (GEFe@Mn2O3) nanoparticles (NPs) was achieved using a green process with Cynoglossum zeylanicum extract. The synthesized nanoparticles were characterized by XRD, FTIR, DLS, PL, and FESEM analysis. The antibacterial activity of GEMn?O? and GEFe@Mn?O? NPs was tested against S. aureus. GEFe@Mn?O?NPs showed significant antibacterial activity as compared to the GEMn?O?NPs. The antioxidant activity of GEMn?O? and GEFe@Mn?O? NPs was studied again using the DPPH assay. Cytotoxicity assays demonstrated that GEMn?O? and GEFe@Mn?O? NPs exhibit significant anticancer activity against a human blood cancer cell line (MOLT-4). The findings indicate a strong correlation between the increased oxygen vacancies of the GEFe@Mn?O? NPs and their enhanced biocidal properties. This suggests that GEFe@Mn?O? nanoparticles (NPs) are promising candidates for antibacterial and anticancer applications due to their unique physicochemical properties, including enhanced redox activity, reactive oxygen species (ROS) generation, and potential for targeted cellular interaction. The incorporation of iron (Fe) and manganese oxide (Mn?O?) provides synergistic effects that can disrupt microbial cell membranes and induce apoptosis in cancer cells through oxidative stress. Moreover, the engineered nanostructure of GEFe@Mn?O? NPs may offer improved biocompatibility and the ability to penetrate biological barriers, making them suitable for therapeutic delivery and biomedical interventions. 2025 Elsevier B.V. -
NiFe2O3 and carboxymethyl cellulose modified NiFe2O3 nanoparticles: synthesis, antibacterial activity, and zebrafish embryo bio-evaluation
The alarming rise in multidrug-resistant bacterial infections has necessitated the development of novel and biocompatible antimicrobial agents. In this study, NiFe2O3 nanoparticles were prepared using co-precipitation method. The NiFe2O3 nanoparticles were functionalized with carboxymethyl cellulose to enhance their stability, dispersibility, and biological activity. The characterization results revealed that the CMC-modified NiFe2O3 nanoparticles exhibited an enhanced physicochemical property when compared to bare NiFe2O3. The hydrodynamic diameter of the CMC-modified NiFe2O3 nanoparticles were found to be 202.3 nm. The crystallite size of the nanoparticles was found to be 28.2 nm for NiFe2O3 and 24.3 nm for CMC-NiFe2O3. Fourier-transform infrared spectra revealed the effective functionalization of CMC through typical O[sbnd]H, C[sbnd]H, and C[sbnd]O[sbnd]C vibrations. The HRTEM results revealed the homogenous particle morphology with negligible aggregation. BET analysis indicated a high surface area of 85.75 m2/g and a pore volume of 1.789 cm3/g, showing a mesoporous structure. The optical studies demonstrated a narrowed band gap from 3.22 eV to 3.12 eV, and lower PL intensity, implying better charge separation and higher surface defects. Antibacterial activity, assessed by agar well diffusion method, indicated drastically bigger zones of inhibition for CMC-NiFe2O3 over bare NiFe2O3, against Shigella dysenteriae and Proteus vulgaris. The antioxidant activity of CMC-NiFe2O3 was determined through DPPH assay which demonstrated dose-dependent radical scavenging activity. The zebrafish embryo toxicity testing revealed dose-dependent developmental anomalies, with high doses (3 mg/mL) triggering pericardial edema, tail malformation, and reduced pigmentation. 2025 Elsevier B.V. -
Nitrogen doped carbon quantum dots@?-Fe2O3/PANI nanocomposite based electrochemical sensor for cadmium ion detection
Cadmium (Cd2+) ions pose significant risks due to their toxic effects even at low concentrations. By integrating nitrogen-doped carbon quantum dots (N-CQDs) with ?-Fe2O3 and polyaniline (PANI), we have engineered a nanocomposite that demonstrates a remarkably high sensitivity and selectivity in detecting Cd2+ ions. The NCQDs@?-Fe2O3/PANI nanocomposite was prepared by using hydrothermal and in-situ polymerization methods. The characterization techniques for an eco-friendly polymer nanocomposite confirm the interactions between N-CQDs, ?-Fe2O3, and PANI. X-ray diffraction analysis shows the nanocomposite possesses a crystal size of 24 0.03 nm. Field-emission scanning electron microscope and high-resolution transmission electron microscope images showed that the spherical N-CQDs are enclosed by irregular ?-Fe2O3 nanoparticles, which are dispersed on the PANI sheets. Further, the particle size distribution analysis indicates an average size of 5.8 nm for the N-CQDs. The electrochemical sensing result suggests that the nanocomposite is effective in sensing the Cd2+ ions with a detection limit of 750 nm. 2025 -
Synergistic effects of NiSe2 on S-doped g-C3N4 for efficient caffeine degradation and electrocatalysis
This work focuses on the synthesis and characterization of NiSe2 on S-doped g-C3N4 to enhance the degradation of caffeine and improve the electrocatalytic performance in both HER and OER. Through a controlled synthesis method, NiSe2 was successfully anchored onto the surface of S-doped g-C3N4, leading to a significant increase in active sites and improved charge transfer. From the PXRD analysis, the crystallite sizes for the planes (210) and (311) were found to be 26 and 21 nm. Morphological analysis confirmed the uniform distribution of NiSe2 nanorod-like structures on the S-g-C3N4 nanosheets. Additionally, the composite demonstrated superior photocatalytic degradation efficiency of 96 % for caffeine under visible light irradiation by the composite, highlighting its potential application in both environmental remediation and energy conversion technologies. After the addition of hydroxyl and singlet oxygen scavengers, the degradation has been decreased to 50.3 % and 47.36 %, highlighting the potential of these radicals in the removal of caffeine. The electrochemical measurements revealed a remarkable increase in HER and OER activities of the NiSe2 on S-doped g-C3N4 composite (?128 mV and 338 mV at 10 mA cm?2 and 50 mA cm?2 respectively) compared to S-doped g-C3N4 and NiSe2 alone. This study highlights the promising role of NiSe2-S-g-C3N4 composites as multifunctional materials in addressing pressing challenges in water treatment and sustainable energy. 2025 Elsevier B.V. -
Green synthesis of palladium nanoparticles from Polyalthia longifolia leaves and Evaluation of its catalytic and antibacterial Activities
This study focuses on the green production of palladium nanoparticles utilizing a sustainable and non-hazardous extract derived from the leaves of Polyalthia longifolia (Pl). The synthesized nanoparticles was named as Pl/Pd (0) and were characterized using TGA, ICP-AES, TEM, FESEM, and XRD analysis. The average size of Pl/Pd (0) nanoparticles was found to be 12 nm and showed excellent activity towards the Suzuki coupling and nitroarene reduction reactions. The catalyst also gave good results for the reusability test for both the reactions. It is noted that the same can be reused in the reaction upto to 5 consecutive cycles. In addition to its catalytic activity, the antibacterial activity of the Pl/Pd(0) was also evaluated against Bacillus subtilis and Pseudomonas aeruginosa bacteria. The nanoparticles had an inhibitory effect on both the test pathogens. 2025 Elsevier B.V. -
Green approach to g-C3N4/Zn2V2O7 nanocomposites synthesis using salvia hispanica powder for photocatalytic degradation of dyes and organic catalysis
Two-dimensional mixed metal oxides have been of interest recently, owing to their distinctive crystal structures and multifunctional properties. This article presents a green and sustainable synthesis approach for zinc vanadate (ZNV) nanoparticles (NPs) using chia seed powder by a green solution combustion method. The synthesized ZNV NPs were then employed for the preparation of g-C3N4/Zinc vanadate (ZNVG) nanocomposites (NCs) at 10 %, 20 %, and 30 % of g-C3N4 compositions. XRD, FT-IR, SEM, EDAX, UVVis, and PL techniques have been performed to characterize the materials entirely. The size of crystallites calculated through the Debye-Scherrer equation for 10 %, 20 %, and 30 % g-C3N4 doping content are 40 nm, 38 nm, and 37 nm, respectively. UVVis spectroscopy shows the redshift in the absorption wavelength and a reduction in the band-gap energy with enhanced light-harvesting features for higher g-C3N4 contents. Photocatalytic investigations have shown that the performance of ZNVG-20 nanocomposite is the optimum; with remarkable degradation efficiencies of 94 % of Rose Bengal and 97 % of Methylene Blue dyes after 180 min. Excellent degradation results were obtained for mixed dyes containing Rose Bengal, Methylene Blue and Methyl Orange and also for environmentally challenging substrates such as rangoli colors. Interestingly, the ZNVG composites also acted as good catalysts in the Knoevenagel condensation reaction, which exhibited up to 92 % efficiency under blue light irradiation. The present findings indicate the versatile potential of ZNVG nanocomposites as photocatalysts and catalysts for addressing environmental and synthetic challenges in a sustainable manner. 2025 Elsevier B.V. -
Facile green synthesis of MnV2O6 nanoparticles: Photocatalytic studies and selective oxidation of aromatic alcohols
Advances in nanotechnology play a crucial role in developing reliable and environmentally friendly nanoparticles (NPs). The green synthesis method is one among them and aims to eliminate toxic by-products. Developing low-cost and highly efficient photocatalysts is essential to accelerate these reactions. To perform this, it is successfully synthesized manganese vanadate NPs using eco-friendly Butea monosperma leaves by the solution combustion method, and the synthesised NPs were characterized to examine their structural, optical, and morphological properties. The XRD pattern confirms that the synthesised MnV2O6 (MVO) NPs possess a monoclinic structure with an average crystallite size of about 67 nm. UVVis spectroscopy shows a band gap of 1.69 eV indicating the suitability of the materials in the Visible region. The photocatalytic activity of the resulting MVO NPs was evaluated and good photocatalytic activity for the degradation of methylene dye. Further, experiments were conducted at various parameters to optimize the catalyst and show the rate constant of 0.00467 min?1. catalytic activity of MVO NPs was also studied for the selective oxidation of aromatic alcohols. Among the various oxidizing agents and solvents used in optimization studies, tBuOOH (oxidizing agent) and CH3CN (solvent) showed the highest conversion (%) of benzyl alcohol, i.e., 98%. 2025 Elsevier B.V. -
Fabrication of NiO nanoparticles modified with carboxymethyl cellulose and D-carvone for enhanced antimicrobial, antioxidant and anti-cancer activities
Colon cancer is a deadly disease while pathogens such as Klebsiella pneumoniae (K. pneumoniae), Shigella dysenteriae (S. dysenteriae), Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), and Candida albicans (C. albicans) are serious threat to the human health due to their persistent nature and resistant to conventional drugs. This study aims to develop NiO nanoparticles via single one pot chemical approach and to modifying them with natural molecules carboxymethyl cellulose and D-carvone to enhance antioxidant, anticancer and antibacterial activity. The NiO and NiO-CMC-Dcar exhibit fcc structure confirmed by XRD. The band gap values were found be 4.15 eV for NiO and 4.23 eV for NiO-CMC-Dcar nanocomposite. DLS study confirmed that the mean particles diameter of NiO and NiO-CMC-Dcar were 154.1 nm and 130.3 nm respectively. The TEM and SEM analysis confirmed that both NiO and NiO-CMC-Dcar samples were roughly spherical. PL emission spectra of NiO-CMC- Dcar nanoparticles at 426 nm and 506 nm indicate the electronic structural modification due to incorporation of CMC and Dcar molecules in to NiO materials. The green emission observed at 506 nm is due to oxygen vacancy that can be correlated to production of more reactive oxygen species (ROS) to kill microorganism. The experimental results show that the NiO-CMC- Dcar nanoparticles exhibit enhanced antimicrobial, anticancer and antioxidant activity when compared to NiO alone. 2024 Elsevier B.V.