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Revealing the synergistic potential of Ti3C2 MXene/Vanadium sulfide composite for enhancing electrochemical water splitting
The development of advanced materials for sustainable energy solutions is more critical than ever, and efficient electrocatalysts are at the forefront of this research. MXene-based materials have garnered significant focus for their electrocatalytic uses due to their high electrical conductivity, hydrophilicity, and tunable surface chemistry. Here, we highlight the innovative work on Ti3C2/V3S4 composites for efficient hydrogen evolution reaction (HER). The Ti3C2 MXene serves as a conductive matrix, while V3S4, a transition metal sulfide, enhances catalytic activity by providing active sites for HER. Integration of V3S4 into the MXene structure increases the surface area and introduces mesoporous channels that improve electron transfer and electrolyte accessibility. Notably, the composite exhibits an enhancement in surface area (45 m2g-1) and pore diameter (11.6 nm) compared to pristine Ti3C2 MXene. Electrochemical measurements demonstrate that the Ti3C2/V3S4 composite has superior hydrogen evolution activity with a lower overpotential of 188 mV and excellent stability compared to bare Ti3C2 MXene. As the demand for clean energy grows, these findings represent a significant step towards the formulation of top-performing materials for water splitting, positioning MXene-based hybrids as a promising solution in the field of renewable energy. This work is a testament to how material innovations can drive progress in hydrogen production technologies, paving the way for cleaner, greener energy systems. 2025 Hydrogen Energy Publications LLC -
Bifunctional CoPBO/Co-MOF composite electrocatalyst for energy-efficient hydrogen evolution by urea-assisted water splitting
Urea oxidation reaction (UOR) offers a lower energy alternative to generate hydrogen from urea-based wastewater while simultaneously contributing to environmental remediation. However, the commercial viability of this process is hindered by the inability of the electrocatalyst to achieve higher current densities for UOR due to the competition with the OER. In this study, a cobalt-MOF-derived CoPBO/Co-MOF composite electrocatalyst was synthesized over Ni foam using a solvothermal method followed by a simple chemical reduction method for UOR. The CoPBO/Co-MOF@NF demonstrated excellent electrocatalytic bifunctional activity with low potentials of +1.32 V and ?0.095 V for UOR and HER, respectively, at 100 mA/cm2 in 1 M KOH +0.33 M urea solution. Under industrial-level alkaline conditions (6 M KOH), the potential requirement for UOR is further decreased to 1.14 V, also achieving a high current density of 1 A/cm2 at only 1.35 V, which is below the thermoneutral voltage for water splitting. Comprehensive electrochemical kinetic analysis revealed that the CoPBO/Co-MOF composite effectively combines the attributes of CoPBO, for strong OH? adsorption and CoOOH formation, with the affinity of Co-MOF for urea adsorption and CO2 desorption, leading to enhanced UOR performance. Furthermore, in a zero-gap electrolyzer configuration, the CoPBO/Co-MOF@NF catalyst demonstrated remarkable efficiency in actual cow urine (with 1 M KOH), requiring only 1.39 V to achieve a current density of 100 mA/cm2 which is 0.5 V lower than in urea-free water splitting. 2025 -
Advancing energy production and storage: Polypyrrole/V2O5/MnO2 composite as a high-performance electrocatalyst
The rise in energy needs in our society has enhanced the requirement for energy production and storage studies. The electrocatalytic hydrogen evolution reaction and supercapattery studies pave the way for producing and storing energy effectively. There is a lot of ongoing work on synthesizing efficient electrocatalysts for such energy related applications. In this study, polypyrrole/V2O5/MnO2 electrocatalyst is synthesized, and various characterization techniques have been utilized for analyzing the formation of the composite. The N2 adsorption-desorption analysis demonstrates the average surface area of the polymer composite as 136.3 m2/g. The high average surface area value suggests the availability of surface active sites on the synthesized polymer composite for energy production and storage. The polypyrrole/V2O5/MnO2 electrocatalyst shows an overpotential of 192 mV and a specific capacity of 1736.1C/g. The synthesized catalyst is used for fabricating an asymmetric supercapacitor, which demonstrates an energy density of 46.8 Wh/kg and a power density of 714.2 W/kg. Polypyrrole/V2O5/MnO2 electrocatalyst is proven to be a competent material for supplementing the energy requirements of our society. 2025 Hydrogen Energy Publications LLC -
Experimental screening of a series of earth-abundant bi-metallic phospho-boride electrocatalysts for overall seawater electrolysis
Seawater electrolysis offers a promising alternative for large-scale hydrogen production, but its industrial viability is hindered by the lack of efficient electrocatalysts. Herein, a series of metals (M = Ni, Fe, W, Mo, V, Cu, and Mn) were experimentally screened to form a bi-metallic catalyst with CoPB, resulting in CoMPB catalysts. Amongst the screened metals, only the inclusion of Mo, W, V, and Fe was found to be beneficial in improving the seawater-splitting reaction rates. Notably, CoMoPB, CoWPB, and CoVPB required minimal HER overpotentials of 56, 105, and 73 mV, respectively, at 10 mA/cm2 in alkaline natural seawater conditions, while CoFePB (291 mV at 10 mA/cm2) outperformed other Co-M-P-B counterparts for OER. The addition of a second metal to CoPB enhances activity, conductivity, and surface reactivity by modulating electron density, optimizing it for seawater splitting. Further, the CoWPB/NFHER || CoFePB/NFOER combination yielded the lowest cell potential of 1.59 V at 100 mA/cm2 and sustained operation for over ?65 h in alkaline natural seawater with ?98 % OER selectivity. The same combination, when integrated into an advanced seawater electrolyzer with zero-gap assembly, required a cell voltage of ?1.94 V to achieve 0.5 A/cm2, demonstrating strong commercial potential. 2025 Hydrogen Energy Publications LLC -
Tailoring acid-base sites and oxygen vacancies in boron- and sulfur-integrated cobalt oxide for high-performance NaBH4 dehydrogenation
Catalytic hydrolysis of sodium borohydride (NaBH4) offers an effective route for on-demand hydrogen generation. In this study, we develop a sulfur and boron modified cobalt oxide catalyst (S-B-CoxOy), through controlled calcination, for hydrogen production from NaBH4. The catalyst achieves a high hydrogen generation rate of 5,400 mL min?1 g?1, facilitated by synergistic enhancements in crystallinity, defect density, and acid-base site distribution. Sulfur and boron incorporation enhances oxygen vacancies and increases active site density, promoting efficient adsorption and activation of NaBH4 and water. NH3-TPD and CO2-TPD confirm balanced acid-base functionalities crucial for electron transfer and intermediate stabilization. A thermally induced phase transition from Co3O4 to CoO, along with increased surface area, further boosts activity. Kinetic studies reveal a zero-order dependence on NaBH4 concentration, demonstrating that the reaction rate is primarily governed by the catalyst's surface properties. This work highlights the importance of defect engineering and surface tuning for efficient hydrogen generation. 2025 -
Hydrogen-enriched dual-fuel CI engine fueled with Mahua biodiesel and hybrid nano-additives: Integrated experiments, explainable machine learning, and multi-objective optimization
Hydrogen-enriched dual-fuel compression-ignition (CI) engines are a potential pathway towards higher efficiency and lower carbon-intensive emissions. Studies conducted so far have considered hydrogen enrichment, biodiesel fuels, nano-additives, and data-driven optimization as separate entities; hence, there is no integration or comprehensive understanding about them, which leads to an efficiency-nitrogen oxides trade-off. This study presents an integrated experimental-machine learning-explainable artificial intelligence-multi-objective optimization framework for a hydrogen-assisted dual-fuel CI engine fueled with a Mahua biodiesel-diesel (B20) blend and hybrid nano-additives (Al2O3TiO2 and CeO2-MWCNT, 50-100ppm). Experimental results indicated that hydrogen enrichment hybridized with nano-additives improves brake thermal efficiency by 8-14% and reduces brake-specific fuel consumption by 10-18%. HC, CO, and smoke emissions are reduced by up to 35%, 32%, and 45%, respectively. There is a moderate increase in NOx by 12-28%. Machine-learning models achieved high predictive accuracy (R2>0.99). The XGBoost exhibited superior generalization. The SHapley Additive exPlanations analysis found that the dominant factors were engine load, the hydrogen energy share, and the concentration of nano-additives. The XGBoost-Multi-Objective Grey Wolf Optimizer (XGBMOGWO) framework created Pareto-optimal solutions showing a strong and interpretable pathway for advancing trade-offs between efficiency and emissions in dual-fuel engines. 2026 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies. -
Migrant minds, shifting selves: Navigating relationships and identity in internal migration
Human migration brings about changes in personal, social, cultural, political, and economic facets of life. This study examined the pre-migratory and post-migratory contexts of emerging adults in India to explore their connection to the existing relationships at migration origin, and upcoming interactions at migration destination. A qualitative method was used to capture the subjective experiences of emerging adults from middle SES, who migrated for education or employment reasons from rural, semi-urban, or urban areas. The migration experiences of these 1829 year-old emerging adults were analyzed through the lens of the social-cognitive model of transference. Semi-structured interviews of 17 internal migrants were conducted to learn about their experience residing away from home. Data analysis revealed schemas concerning significant others interfering with their new relationships at migration destination. Narratives of attachment, support, and conflict shaped their new relationship and self-perception at the migration destination. 2026 Elsevier Ltd. -
Tuning WO3 film properties for electrochromic applications via annealing and oxygen pressure
The objective of this investigation was to examine the intricate relationship between annealing temperature and oxygen partial pressure (PaO2) in regard to morphological, structural, and electrochemical properties of tungsten trioxide (WO3) films that were produced through sputtering. The films were deposited under two different PaO2 values, specifically 0.3 mTorr and 0.5 mTorr, and then underwent annealing at various temperatures: room temperature, 100, 200, 300, and 400 degrees Celsius. X-ray diffraction (XRD) analysis revealed a temperature-dependent transition from an amorphous to a crystalline phase. Morphological analyses conducted with scanning electron microscopy (SEM) indicated a trend towards a smoother surface as both the annealing temperature and PaO2 rose. At 400 C, the films exhibited a granular surface finish. Significantly, the film fabricated at 0.3 mTorr and subjected to room temperature (RT) annealing showed cracks, indicating inherent stress in the film. Electrochemical evaluations revealed that the WO3 film deposited at 0.5 mTorr and annealed later at 200 C demonstrated enhanced redox performance, better diffusion of ions, and remarkable reversibility. Impressive results were demonstrated in optical studies, attaining 83 % optical modulation, colouration efficiency (CE) up to 30.54 cm/C, and swift switching durations of 1.17 s for colouration and 0.82 s for decolouration. Moreover, cycling tests showed negligible degradation after 100 cycles for the films deposited at 0.5 mTorr PaO2 and treated at 200 C, emphasizing their resilience. This study furnishes a comprehensive knowledge of the consequences of annealing temperature and PaO2 collectively on WO3 films, highlighting the novel strategy of enhancing electrochromic efficacy by modifying temperature and meticulously balancing the PaO2, thus contributing to the progress of energy-efficient smart materials. 2025 -
Performance evaluation of multi band disk-shaped terahertz MIMO antenna with hexagon slots on ground for future 6?G and terahertz communication system
In this paper, a four-port wideband MIMO antenna is developed for future 6 G wireless communication systems. The proposed disk-shaped antenna consists of four identical disk-shaped elements arranged uniformly around a circular structure. This uniform arrangement helps maintain geometric balance and minimizes mutual coupling. All the disk patterns are arranged equidistantly around the centrally etched flower-like structure, which ensures the symmetrical geometry of the proposed antenna. These slots are helpful in generating a super-wide bandwidth ranging from 1.81 THz to 4.1513 THz. To further enhance the efficiency of the antenna, hexagonal slots are etched on the ground plane. The hexagonally etched slots on the ground reduce signal reflection losses. The overall dimensions of the four-port MIMO antenna are 800 800 50 m , and it is designed on a silicon substrate with a relative permittivity of 11.9. The proposed antenna achieves a super-wide bandwidth ranging from 0.926 THz to 5.5411 THz and a peak gain of 7 dB. MIMO performance parameters such as diversity gain, Total Active Reflection Coefficient (TARC), Envelope Correlation Coefficient (ECC), and Channel Capacity Loss (CCL) are evaluated, and all lie within acceptable ranges. The disk-shaped antenna demonstrates super-wideband characteristics, high resolution, and a low reflection coefficient. The disk-shaped antenna operates at 1.8175 THz, 2.5911 THz, 3.286 THz, and 4.1513 THz, with reflection coefficients of ?28.02 dB, ?35.723 dB, ?37.11 dB, and ?32.35 dB, respectively. Considering to its compact size, wide bandwidth, and stable radiation characteristics, the proposed disk-shaped antenna is well suited for high-speed THz communication and beyond-6G wireless applications. Copyright 2026. Published by Elsevier GmbH. -
Engineered core-shell nanocomposite fibres incorporating bio-ceramics and bioactive molecules for wound repair
Skin plays a major role in protecting the body from external injuries and contaminants. Despite the self-healing mechanisms of the body, wound healing has several limitations, such as being time-consuming, leading to scar formation, and susceptibility to infections. In this study, a novel coreshell nanofibre membrane was designed to protect wounds and prevent secondary trauma, thereby enhancing the wound healing process. A coreshell nanofibre membrane was prepared using polycaprolactone (PCL) as the core polymer loaded with astaxanthin (ASTX) and bioglass (BG), while the shell was made from polylactic acid (PLA) containing nanohydroxyapatite (nHA) to support faster wound healing. The surface structure, morphology, and hydrophilicity of the fibres were extensively characterised. The analysis revealed uniform, well-organised, interconnected coreshell nanocomposite fibres ideal for cell adhesion and growth. In vitro studies have demonstrated enhanced cell viability and wound closure in mouse L929 fibroblast cells. Immune response studies on test membranes loaded with ASTX, BG, and nHA revealed strong anti-inflammatory and antibacterial activities against Gram-positive and Gram-negative bacteria. In vivo studies indicated favourable cellular responses and superior wound healing potential of membranes incorporated with ASTX, BG and a higher concentration of nHA. These findings highlight the potential of coreshell nanofibre membranes as an innovative wound dressing for full-thickness skin injuries, showing significant promise for biomedical applications, especially in wound healing treatments. 2025 -
Influence of alkali treatment on physiochemical and morphological properties of palmyra fibers
As a part of sustainable development in construction, natural fibers are used as reinforcement in cement composites. The degradation of these natural fibers in matrix has led to growing interest among researchers to enhance the fiber properties by adopting suitable treatment techniques. This research focuses on examining the influence of alkali treatment on various aspects, including the physical, chemical, crystallinity, mechanical and surface characteristics of palmyra fibers. Herein, the palmyra fibers were immersed in alkaline solution for different duration (30 minutes, 60 minutes and 120 minutes) to arrive at optimum treatment period. The investigation utilizes XRD, FTIR, SEM and EDS analysis to gain insights into these properties. The findings indicated that the treatment effectively removed excess amorphous components like extractives, hemicellulose and lignin leading to the increase in crystallinity index and surface roughness. The crystallinity index increased by 11 %, 13 % and 23 % for 30 minutes, 60 minutes and 120 minutes treatment respectively. The water absorption of palmyra fibers reduced by 13 %, 14 % and 14 % for 30 minutes, 60 minutes and 120 minutes treatment duration respectively. Additionally, SEM-EDS exhibited best results for 60 min treatment of fibers, with 38 % increase in Oxygen to Carbon ratio of cellulose compared to untreated fibers. Among the different treatment duration, the 60 minutes treatment duration of fibers in 0.5 M sodium hydroxide solution has exhibited considerable enhancement in properties. These enhancements in palmyra fiber properties post-alkali treatment suggests their potential utility in the reinforcement of composites using alkali treated palmyra fibers. 2024 The Authors -
Changes in the dynamic profile of beneficial metabolites during Panax ginseng somatic embryogenesis
In this study, we characterized the dynamic changes in the metabolite profiles of Panax ginseng during somatic embryogenesis (SE) to explore their stage-specific functional potential. We quantified phenolic compounds and amino acids using high-performance liquid chromatography (HPLC), while bioactive metabolites were identified through LC-MS/MS analysis. During SE, the total phenolic content (TPC) and total flavonoid content (TFC) significantly increased at the globular-to-torpedo (GT) stage, exhibiting enhanced antioxidant activity. Anti-inflammatory activity and cytoprotective effects peaked during the young plantlet (Yp) stage, driven by the accumulation of terpenoid metabolites, such as ginsenosides Rd and sarcostin. Additionally, at the embryogenic stem cell (ESC) stage, stress-related amino acids such as GABA and proline, along with metabolites like venlafaxine, clebopride, and nemonapride, which possess neuromodulatory properties, were distinctively accumulated. These results reveal the stage-specific metabolites and associated biological characteristics of ginseng SE, demonstrating the potential of ginseng-derived metabolites for pharmacological and nutraceutical applications. 2025 The Authors -
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. -
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. -
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. -
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. -
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. -
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 -
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. -
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.