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• Wider variety of artefacts needs to be conserved. • NPs based coating have the potency to replace the traditional coating materials. • The NPs improved the photo-catalysis, hydrophobicity and antibacterial properties. The progression in the use of nanostructured metal oxide or metal oxide based polymeric nanocomposite for the conservation and refurbishment of cultural heritage are presented in this review. Starting from the definition of nanoparticles, their major synthesis techniques, the paper briefly describes the utilization of various metal oxide nanoparticles and metal oxide based polymeric nanocomposite coatings and their surface protection functions including self-cleaning, increased photocatalytic activity, biocidal effects, UV blocking properties and compatibility with the different types of substrates including wood, stones, bricks and paper focussing on their potential usage and their application in the arena of remediation of cultural heritage. [Display omitted] [ABSTRACT FROM AUTHOR]

The utilization of synthetic plastics has resulted in environmental and human health concerns. Consequently, there is a growing focus on developing eco-friendly alternatives like polylactic acid (PLA). Nonetheless, its drawbacks include slow crystallization, vulnerability to UV radiation, and absence of antibacterial properties. One potential strategy involves integrating nano-cellulose (NC) and metal oxide nanoparticles into PLA to enhance its antibacterial features and mechanical robustness. The NC was extracted from the leaves of Borassus flabellifer and further treated with lactic acid to obtain surface-modified NC (SMNC). Besides, the Zinc oxide nanoparticles (ZnO NPs) were green-synthesized using the B. flabellifer leaves extract and further characterized through various analytical techniques such as SEM, XRD, and FTIR. The optimized bio-composite ratio was 89.5 mg of PLA, 3.5% (w% of PLA) of SMNC, and 7% (wt% of PLA) of ZnO NPs based on the appearance, water contact angle (WCA), and antimicrobial activities of the bio-composite film. The PLA-SMNC-ZnO NPs film was further characterized and compared with PLA and PLA-SMNC films for its structural, mechanical, and thermal properties. The PLA-SMNC- ZnO NPs film exhibited an improved tensile strength of 13.9 MPa and Young's modulus of 0.00689 GPa than PLA and PLA-SMNC. Also, the thermal stability of PLA-SMNC-ZnO NPs film was 320 °C from TGA. Additionally, PLA-SMNC- ZnO NPs film exhibited reduced water absorption and improved resistance to UV radiation. In conclusion, these findings validate the potential of the ZnO NPs derived from B. flabellifer's leaves in improving the versatility of PLA. [ABSTRACT FROM AUTHOR]

Green synthesis is an easy, safe, and environmentally beneficial nanoparticle creation method. It is a great challenge to simultaneously improve the capping and stabilizing agent carrier separation efficiency of photocatalysts. Herein, Zn-doped Titanium dioxide (TiO2) nanoparticles with high exposure of 360 nm using a UV/visible spectrophotometer were prepared via a one-step hydrothermal decomposition method. A detailed analysis reveals that the electronic structures were modulated by Zn doping; thus, the responsive wavelength was extended to 600 nm, which effectively improved the visible light absorption of TiO2. We have optimized the different parameters like concentration, time, and temperature. The peak for TiO2 is located at 600 cm-1 in FTIR. A scanning electron microscope revealed that TiO2 has a definite shape and morphology. The synthesized Zn-doped TiO2NPs were applied against various pathogens to study their anti-bacterial potentials. The anti-bacterial activity of Zn-doped TiO2 has shown robust against two gram-ve bacteria (Salmonella and Escherichia coli) and two gram + ve bacteria (Staphylococcus epidermidis and Staphylococcus aureus). Synthesized Zn-doped TiO2 has demonstrated strong antifungal efficacy against a variety of fungi. Moreover, doping TiO2 nanoparticles with metal oxide greatly improves their characteristics; as a result, doped metal oxide nanoparticles perform better than doped and un-doped metal oxide nanoparticles. Compared to pure TiO2, Zn-doped TiO2 nanoparticles exhibit considerable applications including antimicrobial treatment and water purification. [ABSTRACT FROM AUTHOR]

Poly (vinyl chloride) (PVC) films modified with ethylenediamine (en) and doped by nanoparticles (TiO2, ZnO, NiO, and MgO). A mixture of 0.5 g PVC/en dissolved in THF and 0.01 wt % of nanoparticles were used in doping PVC to produce the nanocomposite films. All modified PVC films were characterized by different analysis techniques such as Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance Spectrometer (NMR), diffusive reflectance spectroscopy (DRS), X‐ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The DRS was used to analyse the scattered IR energy of the samples at wavelengths between (250–1350 nm). The optical properties and oscillator strength were also studied, the transmittance and reflectance values declined for the PVC films, and the absorption coefficient was observed between (79–89 %). The direct energy gap decreased from 4.6 to 1.9, and the indirect energy gap reduced from 4.3 to 1.9. The XRD exhibited a semi‐crystalline structure and the SEM test exhibited a porous structure of all samples. The Urbach energy was increased from 0.8772 eV to 14.712 eV, single oscillator energy (Eo ${{E}_{o}}$) was also increased from 6.38 eV to 13.69 eV and the dispersion energy (Ed) ${{(E}_{d})}$ increased from 23.40 eV to 70.63 eV. Moreover, the surface roughness parameters Ra and Rq of the PVC films in modified and doping were increased from 3.86 nm to 8.14 nm, and 5.08 nm to 10.10 nm respectively. So, PVC results show increased optical properties after modification with en and doping by NPs are used in the light conversion and aerospace industries. [ABSTRACT FROM AUTHOR]

In this research, a suitable and efficient CoFe2O4@ZnO@Bentonite nano-catalyst was designed and synthesized by using zinc oxide (ZnO) and cobalt ferrite (CoFe2O4) nanoparticles and bentonite by microwave irradiation. Characteristics of the synthesized nanocomposite were investigated by Fourier transform infrared (FT-IR), scanning electron microscope (SEM), energy dispersive X-ray (EDX), transmission electron microscope (TEM), X-ray diffraction (XRD), Bruner-Emmett-Teller (BET) and vibrating sample magnetometer (VSM) techniques. The produced catalyst was effectively employed as a supported solid acid catalyst in mildly agitated three-component reactions involving aromatic aldehydes, 4-hydroxycoumarin, and 1,3-dimethyl-barbituric acid in a single pot to produce benzylbarbiturocoumarins. Starting materials were condensed via three C-C bond formation by CoFe2O4@ ZnO@Bentonite as an efficient, recyclable, and environmentally safe nanocatalyst to obtain target products. The advantages of this method include using a natural substrate, small amounts of catalyst, aqueous media, performing reactions at ambient temperature, simple separation and purification of products, and good yields with short reaction times. [ABSTRACT FROM AUTHOR]

The access to drinkable water is a critical challenge in the context of the rising urbanization and industrialization, calling for advanced technologies to clean contaminated waters and wastewater. Here we review the use of metal oxides biochar composites to treat pollution by hevay metals and dyes. We focus on the synthesis of metal oxide nanobiochar; the treatment of pollution by mercury, lead, methylene blue and methyl orange; life cycle analysis; and techno-economical assessment. Metal oxide nanoparticles can act as photocatalysts to allow for the complete mineralization of organic pollutants. For instance, the doping of tin oxide nanoparticles into biochar surface degraded 99.5% of methylene blue dye after 105 min. Ball-milled magnetic nanobiochar achieves 99% mercury removal in 720 min. The presence of biochar enhanced the uptake of contaminants on nanoparticles and facilitated the photocatalytic reaction [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is growing into a major public health crisis worldwide. The reducing alternatives to conventional agents starve for novel antimicrobial agents. Due to their unique magnetic properties and excellent biocompatibility, iron oxide nanoparticles (IONPs) are the most preferable nanomaterials in biomedicine, including antibacterial therapy, primarily through reactive oxygen species (ROS) production. IONP characteristics, including their size, shape, surface charge, and superparamagnetism, influence their biodistribution and antibacterial activity. External magnetic fields, foreign metal doping, and surface, size, and shape modification improve the antibacterial effect of IONPs. Despite a few disadvantages, IONPs are expected to be promising antibacterial agents of a new generation. [ABSTRACT FROM AUTHOR]

This work aimed to develop antifouling coatings for maritime structures and sailing vessels by the integration of nanoparticles as very effective biocidal agents. The paint compositions were created by combining several components with a binder known as linseed alkyd resin. The preparation of TiO2 and SiO2 nanoparticles was conducted by the ball milling technique, followed by their application as pigments in nano paints. The corrosion characteristics of these coatings were examined after the incorporation of the nano paint, to diminish fouling and enhance antibacterial efficacy on maritime vessels. The enhancement of antifouling paint efficacy is expected to be substantial as a result of the advancement in nanoparticle-based compositions that exhibit biocidal capabilities. To evaluate the efficacy of nanocoatings, miniature specimens were submerged in a marine environment for 120 days. The coated samples underwent analysis by various techniques including scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction. Furthermore, an assessment was conducted to determine the efficacy of the protective characteristics exhibited by the coated tiny mild-steel samples. This evaluation involved subjecting the samples to a 120-day immersion in the ocean environment. The inclusion of SiO2 and TiO2 nanoparticles in the paints yields significant corrosion protection for the coated samples, in contrast to those lacking nanoparticles. Additionally, the latter exhibits superior anti-fouling properties. [ABSTRACT FROM AUTHOR]

The preparation of two‐dimensional (2D) materials often requires complicated exfoliation procedures having low yields. The exfoliated nanosheets are prone to thermal aggregation and unsuitable for thermocatalysis. Herein, a scalable approach produces 2D catalyst precursors well‐distributed and mixed at the nanoscale. Using continuous microfluidization and single‐layer layered double hydroxide (LDH) synthesis, the prepared suspension contained exfoliated hexagonal boron nitride (h‐BN) nanosheets and single‐layer LDHs. The increased contact area between h‐BN and LDHs enables the formation of highly dispersed MnCoAl mixed metal oxide nanoparticles anchored on h‐BN nanosheets after calcination. In the selective catalytic reduction of NOx with NH3 (NH3‐SCR, a representative thermocatalytic application), this nanocomposite demonstrates a record turnover frequency of 0.772 h−1 among reported Mn‐based NH3‐SCR catalysts, with high NOx conversion and high N2 selectivity at low temperatures. By creating 2D precursors mixed at the nanoscale, this new synthetic approach can realize the scalable production of highly efficient thermocatalysts. [ABSTRACT FROM AUTHOR]

The extensive use of carbon nanoparticles (CNPs) inevitably results in their introduction into soil and groundwater, which poses a significant risk to the safety of these natural resources. Therefore, it is crucial to understand the transport behavior of CNPs in the subsurface environment and how it affects the transport of co-contaminants such as heavy metals, organic compounds, nano-plastics, engineered metal and metal oxide nanoparticles. This review focuses on recent advancements in research on the transport behaviors of CNPs in porous media and its effect on the transport of co-contaminants, with respect to the mechanisms associated with CNPs transport and the mechanisms of action of CNPs on co-contaminant transport, as well as the factors that influence these processes. Results of the existing research indicate that aggregation, attachment, detachment, straining, blocking and ripening are the primary processes governing CNPs transport due to their unique physiochemistry. CNPs can either act as carriers, facilitating the transport of co-contaminants, or as competitors, hindering the deposition of co-contaminants. Additionally, they can serve as collectors for co-contaminant deposition or co-deposit with co-contaminants, inhibiting their transport. The interactions between CNPs, co-contaminants, and the medium determine the exact role played by CNPs in co-contaminant transport. The processes of CNPs transport and its effect on co-contaminant transport are affected by the physicochemical properties of CNPs and porous media, as well as the chemistry and hydrodynamics of groundwater. This review article is of great significance for risk assessment of CNPs in soil and groundwater. [ABSTRACT FROM AUTHOR]

Flexible optoelectronics, based on non-planar substrates, hold promise for diverse applications such as wearables, health monitors, and displays due to their cost-effective manufacturing methods. Despite the superior properties of metal oxides, the challenge of processing them at high temperatures incompatible with plastic substrates necessitates innovative annealing approaches. Photonic curing, which delivers microsecond to millisecond broadband (200–1500 nm) light pulses on a sample, emerges as a viable solution. Depending on the optical properties, the targeted film absorbs the radiant energy resulting in rapid heating while the transparent substrate absorbs a minimal amount of light and remains at ambient temperature. The light intensity can be high, but since the light pulse is short, the total energy absorbed by the sample remains low and will not damage the plastic substrate. This perspective explores the innovative application of photonic curing to fabricate flexible metal oxide optoelectronics, including thin-film transistors, metal–insulator–metal devices, solar cells, transparent conductors, and Li batteries, emphasizing the conversion of sol–gel precursors to metal oxides. However, this technique was initially developed for sintering metal nanoparticles to conductive patterns and poses intriguing challenges in explaining its mechanism for metal oxide conversion, especially considering the limited absorption of visible light by most sol–gel precursors. The review delves into UV-induced photochemistry, common flexible metal-oxide optoelectronic components, and non-intuitive distinctions between photonic curing and thermal annealing. By elucidating the distinctive role of photonic curing in overcoming temperature-related challenges and advancing the fabrication of flexible metal oxide optoelectronics, this perspective offers valuable insights that could shape the future of flexible optoelectronics. [ABSTRACT FROM AUTHOR]

Green synthesis is a reliable way to synthesize metal oxide nanoparticles (NPs) without affecting the environment. Plant extracts act as reducing agents that favor the synthesis of NPs. In this study, jackfruit aqueous extract was used as a fuel in the solution combustion synthesis of lanthanum oxide (La2O3) NPs. X-ray diffraction (XRD) confirmed the formation of the hexagonal structure of La2O3 NPs. The scanning electron microscope (SEM) and energy dispersive X-ray (EDS) spectrum confirm the needle-shaped morphology and purity of the La2O3 NPs, respectively. Furthermore, La2O3 was utilized as a photocatalyst for the photodegradation of methylene blue dye under visible light radiation, demonstrating high efficiency within 90 min of light irradiation. The electrochemical characteristics of La2O3 were studied using a carbon paste electrode in a 0.1 M HCl solution. These La2O3 samples exhibited superior sensitivity in cyclic voltammetry tests towards the detection of ascorbic acid and lead nitrate. Consequently, La2O3 holds potential for applications in electrochemical sensor technology. [ABSTRACT FROM AUTHOR]

Precisely tuning bicomponent intimacy during reactions by traditional methods remains a formidable challenge in the fabrication of highly active and stable catalysts because of the difficulty in constructing well‐defined catalytic systems and the occurrence of agglomeration during assembly. To overcome these limitations, a PtRuPNiO@TiOx catalyst on a Ti plate was prepared by ultrasound‐assisted low‐voltage plasma electrolysis. This method involves the oxidation of pure Ti metal and co‐reduction of strong metals at 3000°C, followed by sonochemical ultrasonication under ambient conditions in an aqueous solution. The intimacy of the bimetals in PtRuPNiO@TiOx is tuned, and the metal nanoparticles are uniformly distributed on the porous titania coating via strong metal‒support interactions by leveraging the instantaneous high‐energy input from the plasma discharge and ultrasonic irradiation. The intimacy of PtRuPNiO@TiOx increases the electron density on the Pt surface. Consequently, the paired sites exhibit a high hydrogen evolution reaction activity (an overpotential of 220 mV at a current density of 10 mA cm−2 and Tafel slope of 186 mV dec−1), excellent activity in the hydrogenation of 4‐nitrophenol with a robust stability for up to 20 cycles, and the ability to contrast stated catalysts without ultrasonication and plasma electrolysis. This study facilitates industrially important reactions through synergistic chemical interactions. [ABSTRACT FROM AUTHOR]

Modelling size-realistic nanomaterials to analyse some of their properties, such as toxicity, solubility, or electronic structure, is a current challenge in computational and theoretical chemistry. The representation of the all-atom three-dimensional structure of a nanocompound would be ideal, as it could account explicitly for structural effects. However, the use of the whole structure is tedious due to the high data management and the structural complexity that accompanies the surface of the nanoparticle. Developing appropriate tools that enable a quantitative analysis of the structure, as well as the selection of regions of interest such as the core-shell, is a crucial step toward enabling the efficient analysis and processing of model nanostructures. The aim of this study was twofold. First, we defined the NanoFingerprint, which is a representation of a nanocompound in the form of a vector based on its 3D structure. The local relationship between atoms, i.e., their coordination within successive layers of neighbours, allows the characterisation of the local structure through the atom connectivity, maintaining the information of the three-dimensional structure but increasing the management ability. Second, we present a web server, called ATENA, to generate NanoFingerprints and other tools based on the 3D structure of the nanocompounds. A case study is reported to show the validity of our new fingerprint tool and the usefulness of our server. The scientific community and also private companies have a new tool based on a public web server for exploring the toxicity of nanocompounds. [ABSTRACT FROM AUTHOR]

Co-exposure soil studies of pollutants are necessary for an appropriate ecological risk assessment. Here, we examined the effects of two-component mixtures of metal oxide nanoparticles (ZnO NPs or goethite NPs) with the insecticide chlorpyrifos (CPF) under laboratory conditions in short-term artificial soil assays using Eisenia andrei earthworms. We characterized NPs and their mixtures by scanning electron microscopy, atomic force microscopy, dynamic light scattering and zeta potential, and evaluated effects on metal accumulation, oxidative stress enzymes, and neurotoxicity related biomarkers in single and combined toxicity assays. Exposure to ZnO NPs increased Zn levels compared to control in single and combined exposure (ZnO NPs + CPF) at 72 h and 7 days, respectively. In contrast, there was no indication of Fe increase in organisms exposed to goethite NPs. One of the most notable effects on oxidative stress biomarkers was produced by single exposure to goethite NPs, showing that the worms were more sensitive to goethite NPs than to ZnO NPs. Acetylcholinesterase and carboxylesterase activities indicated that ZnO NPs alone were not neurotoxic to earthworms, but similar degrees of inhibition were observed after single CPF and ZnO NPs + CPF exposure. Differences between single and combined exposure were found for catalase and superoxide dismutase (goethite NPs) and for glutathione S-transferase (ZnO NPs) activities, mostly at 72 h. These findings suggest a necessity to evaluate mixtures of NPs with co-existing contaminants in soil, and that the nature of metal oxide NPs and exposure time are relevant factors to be considered when assessing combined toxicity, as it may have an impact on ecotoxicological risk assessment. [ABSTRACT FROM AUTHOR]

As per the increasing demand for new sustainable materials and methodologies, green synthesis of metal oxide nanoparticles has drawn the attention of many researchers. However, compared to certain other metal oxides, there has been comparatively less attention towards green synthesis of Ruthenium oxide Nanoparticles (RuNPs). In this paper, RuNPs were synthesized using plant extract of Iris Kashmiriana (found in the high-altitude region of Kashmir in India) and characterized by FT-IR, SEM, EDX, and XRD. Particles were synthesized in the dimensions of 25–30 nm. FT-IR peaks in this 3348 cm-1 infrared spectrum range confirmed Ru-O symmetric stretching while crystalline structure was confirmed by X-ray diffraction. By displaying a zone of inhibition for erythromycin, the synthesized ruthenium oxide nanoparticles exhibit potent antibacterial action against four different pathogens, including Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Streptococcus pneumoniae. [ABSTRACT FROM AUTHOR]

Synthetic dyes play a crucial role in our daily lives, especially in clothing, leather accessories, and furniture manufacturing. Unfortunately, these potentially carcinogenic substances are significantly impacting our water systems due to their widespread use. Dyes from various sources pose a serious environmental threat owing to their persistence and toxicity. Regulations underscore the urgency in addressing this problem. In response to this challenge, metal oxide nanoparticles such as titanium dioxide (TiO2), zinc oxide (ZnO), and iron oxide (Fe3O4) have emerged as intriguing options for dye degradation due to their unique characteristics and production methods. This paper aims to explore the types of nanoparticles suitable for dye degradation, various synthesis methods, and the properties of nanoparticles. The study elaborates on the photocatalytic and adsorption-desorption activities of metal oxide nanoparticles, elucidating their role in dye degradation and their application potential. Factors influencing degradation, including nanoparticle properties and environmental conditions, are discussed. Furthermore, the paper provides relevant case studies, practical applications in water treatment, and effluent treatment specifically in the textile sector. Challenges such as agglomeration, toxicity concerns, and cost-effectiveness are acknowledged. Future advancements in nanomaterial synthesis, their integration with other materials, and their impact on environmental regulations are potential areas for development. In conclusion, metal oxide nanoparticles possess immense potential in reducing dye pollution, and further research and development are essential to define their role in long-term environmental management. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) is considered an attractive option for orthopedic applications due to its density and elastic modulus close to the natural bone of the body, as well as biodegradability and good tensile strength. However, it faces serious challenges, including a high degradation rate and, as a result, a loss of mechanical properties during long periods of exposure to the biological environment. Also, among its other weaknesses, it can be mentioned that it does not deal with bacterial biofilms. It has been found that making composites by synergizing its various components can be an efficient way to improve its properties. Among metal oxide nanoparticles, magnesium oxide nanoparticles (MgO NPs) have distinct physicochemical and biological properties, including biocompatibility, biodegradability, high bioactivity, significant antibacterial properties, and good mechanical properties, which make it a good choice as a reinforcement in composites. However, the lack of comprehensive understanding of the effectiveness of Mg NPs as Mg matrix reinforcements in mechanical, corrosion, and biological fields is considered a challenge in their application. While introducing the role of MgO NPs in medical fields, this article summarizes the most important results of recent research on the mechanical, corrosion, and biological performance of Mg/MgO composites. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles (MONP/s) induce DNA damage, which is influenced by their physicochemical properties. In this study, the high-throughput CometChip and micronucleus (MicroFlow) assays were used to investigate DNA and chromosomal damage in mouse lung epithelial cells induced by nano and bulk sizes of zinc oxide, copper oxide, manganese oxide, nickel oxide, aluminum oxide, cerium oxide, titanium dioxide, and iron oxide. Ionic forms of MONPs were also included. The study evaluated the impact of solubility, surface coating, and particle size on response. Correlation analysis showed that solubility in the cell culture medium was positively associated with response in both assays, with the nano form showing the same or higher response than larger particles. A subtle reduction in DNA damage response was observed post-exposure to some surface-coated MONPs. The observed difference in genotoxicity highlighted the mechanistic differences in the MONP-induced response, possibly influenced by both particle stability and chemical composition. The results highlight that combinations of properties influence response to MONPs and that solubility alone, while playing an important role, is not enough to explain the observed toxicity. The results have implications on the potential application of read-across strategies in support of human health risk assessment of MONPs. [ABSTRACT FROM AUTHOR]

Efficient light sources with emission spanning from visible to infrared range are of central importance for applications including precision spectroscopy and sensing. Under irradiation with constant‐wave (CW) lasers, here, the generation and modulation of incandescence‐like ultra‐broad emission (600–4000 nm) from random aggregates of metal oxide nanoparticles are demonstrated by judicious doping of free carriers, that of any existing photoluminescence process and commercial broadband light sources. It is revealed that this emission is associated with a dominant thermal origin and it is characterized by a pump‐dependent nonlinear response with the maximum order of nonlinearity exceeding 8, which is benefited from the intensified light‐matter interaction mediated by the high density of hot spots in the random plasmonic nanostructures. Moreover, by leveraging the prominent plasmon response, the emission spectra and intensity can be tuned by the Drude terms of the oxide nanoparticles. the use of this broadband infrared (IR) emission is exploited further as the light source for the demonstration of IR spectrometry, exemplified by the examination of organic molecules. The method for producing strong and continuum IR emission based on engineered plasmonic oxide can stimulate further exploitation of miniaturized IR light sources for applications including imaging and sensing. [ABSTRACT FROM AUTHOR]

The advancement in materials for energy storage for supercapacitors has been supported by the current shortage of energy as well as the increasing availability of sources of clean energy. Consequently, two‐dimensional materials based on metal oxide nanoparticles (copper oxide (CuO) and zinc oxide (ZnO), have great potential for the previously discussed utilization. A simple and affordable solid‐state approach was employed to design hybrid nanocomposite based on chitosan (Cs) blended with ZnO and CuO; this nanocomposite was labeled with CZC. The structural, morphological investigation of CZC hybrid nanocomposites, and X‐ray diffraction (XRD) of the prepared nanocomposites were characterized. Consequently, hybrid nanocomposites for application as electrodes for supercapacitor devices were developed. The hybrid nanocomposite (CZC‐3) shows improved cycle stability, high energy density, and a specific capacitance in the electrochemical activity. Remaining at 97.8% of the initial capacitance even after 5000 cycles. These results imply that the hybrid nanocomposite based on Cs/ZnO/CuO has a promising future as a supercapacitor electrode material. Additionally, it provides superior performance to other nanocomposites with a high specific capacitance of 638.3 F/g and about 86.98% capacity retention after 5000 cycles at a current density of 1 A/g. [ABSTRACT FROM AUTHOR]

[Display omitted] The competitive interaction of oxyanions and humic nanoparticles (HNPs) with metal (hydr)oxide surfaces can be used to trace the ligand and charge distribution of adsorbed HNPs in relation to heterogeneity, fractionation, and conformational change. Batch adsorption experiments of HNPs on goethite were performed in the absence and presence of phosphate. The size of HNPs was measured with size exclusion chromatography. The Ligand and Charge Distribution (LCD) model framework was further developed to describe the simultaneous interaction of HNPs and phosphate with goethite. Preferential adsorption decreases the mean molar mass of adsorbed HNPs, independent of the phosphate presence, showing a linear dependency on the adsorbed HNPs fraction. Phosphate ion can be used as a probe to trace the distribution of functional groups and the variation in affinity of HNPs. The spatial distribution of adsorbed HNPs is driven by the potential gradients in the electrical double layer, which changes the conformation of the adsorbed HNPs. At the particle level, the adsorption of heterogeneous HNPs has an affinity distribution, which can be explained by the variation in molar mass (kDa) and density of the functional groups (mol kg−1) of the HNPs. The presented model can simultaneously describe the competitive adsorption of HNPs and phosphate in a consistent manner. [ABSTRACT FROM AUTHOR]

The advanced and highly functional properties of Al2O3 and NiO nanoparticles promote the widespread use of metal oxides as remarkable electroactive materials for sensing and electrochemical applications. The proposed study describes a comparison of the sensitivity and selectivity of two modified wire membrane sensors enriched with Al2O3 and NiO nanoparticles with conventional wire membranes for the quantification of the antidiabetic drug metformin hydrochloride (MTF). The results show linear relationships of the enriched Al2O3 and NiO nanosensors over the concentration ranges 1.0 × 10−10–1.0 × 10−2 mol L−1 and 1.0 × 10−6–1.0 × 10−2 M for both the modified sensors and the conventional coated wire membrane sensors. The regression equations were E mV = (52.1 ± 0.5) log (MTF) + 729 for enriched nanometallic oxides, E mV = (57.04 ± 0.4) log (MTF) + 890.66, and E mV = (58.27 ± 0.7) log (MTF) + 843.27 with correlation coefficients of 0.9991, 0.9997, and 0.9998 for the aforementioned sensors, respectively. The proposed method was fully validated with respect to the recommendations of the International Union of Pure and Applied Chemistry (IUPAC). The newly functionalized sensors have been successfully used for the determination of MTF in its commercial products. [ABSTRACT FROM AUTHOR]

Nanotechnology has emerged as a promising field in pharmaceutical research, involving producing unique nanoscale materials with sizes up to 100 nm via physiochemical and biological approaches. Nowadays more emphasis has been given to eco-friendly techniques for developing nanomaterials to enhance their biological applications and minimize health and environmental risks. With the help of green nanotechnology, a wide range of green metal, metal oxide, and bimetallic nanoparticles with distinct chemical compositions, sizes, and morphologies have been manufactured which are safe, economical, and environment friendly. Due to their biocompatibility and vast potential in biomedical (antibacterial, anticancer, antiviral, analgesic, anticoagulant, biofilm inhibitory activity) and in other fields such as (nanofertilizers, fermentative, food, and bioethanol production, construction field), green metal nanoparticles have garnered significant interest worldwide. The metal precursors combined with natural extracts such as plants, algae, fungi, and bacteria to get potent novel metal, metal oxide, and bimetallic nanoparticles such as Ag, Au, Co, Cu, Fe, Zr, Zn, Ni, Pt, Mg, Ti, Pd, Cd, Bi2O3, CeO2, Co3O4, CoFe2O4, CuO, Fe2O3, MgO, NiO, TiO2, ZnO, ZrO2, Ag-Au, Ag-Cr, Ag-Cu, Ag-Zn, Ag-CeO2, Ag-CuO, Ag-SeO2, Ag-TiO2, Ag-ZnO, Cu-Ag, Cu-Mg, Cu-Ni, Pd-Pt, Pt-Ag, ZnO-CuO, ZnO-SeO, ZnO-Se, Se-Zr, and Co-Bi2O3. These plant-mediated green nanoparticles possess excellent antibacterial and anticancer activity when tested against several microorganisms and cancer cell lines. Plants contain essential phytoconstituents (polyphenols, flavonoids, terpenoids, glycosides, alkaloids, etc.) compared to other natural sources (bacteria, fungi, and algae) in higher concentration that play a vital role in the development of green metal, metal oxide, and bimetallic nanoparticles because these plant-phytoconstituents act as a reducing, stabilizing, and capping agent and helps in the development of green nanoparticles. After concluding all these findings, this review has been designed for the first time in such a way that it imparts satisfactory knowledge about the antibacterial and anticancer activity of plant-mediated green metal, metal oxide, and bimetallic nanoparticles together, along with antibacterial and anticancer mechanisms. Additionally, it provides information about characterization techniques (UV–vis, FT-IR, DLS, XRD, SEM, TEM, BET, AFM) employed for plant-mediated nanoparticles, biomedical applications, and their role in other industries. Hence, this review provides information about the antibacterial and anticancer activity of various types of plant-mediated green metal, metal oxide, and bimetallic nanoparticles and their versatile application in diverse fields which is not covered in other pieces of literature. [ABSTRACT FROM AUTHOR]

Introduction: The green synthesis of metal oxide nanoparticles using plant extracts has emerged as an eco-friendly method. Titanium dioxide nanoparticles (TiO2NPs) were synthesized using Cissus rotundifolia in this study. Titanium dioxide nanoparticles were utilized in restorative medicine for enhanced medicinal properties and in dental composites for their antimicrobial activities. Cissus rotundifolia is recognized as a medicinal plant due to its diverse properties, including mild laxatives, anti-inflammatory, and hyperglycemic activities. Materials and Methods: The antimicrobial activity of the prepared nanoparticles against Lactobacillus Sp. and Streptococcus mutans was evaluated using agar well diffusion method. The bactericidal and bacteriostatic activity of the prepared TiO2NPs was examined using time-kill kinetic analysis. Results: The prepared nanoparticles exhibited potential antimicrobial activity against Lactobacillus sp. (12 mm) at the highest concentration of 100 µg/mL. The prepared nanoparticles also exhibited excellent bactericidal activity against Lactobacillus Sp. and mild bacteriostatic activity against Staphylococcus mutans at the highest concentration of 100 µg/mL. Conclusion: The synthesized TiO2NPs showed significant antimicrobial activity against dental pathogens. The observed anticariogenic activity shows the potential of nanoparticles for dental applications. Hence, the prepared nanoparticles can be used in the field of dentistry as an antimicrobial agent instead of synthetic drugs causing more side effects. [ABSTRACT FROM AUTHOR]

The strong metal–support interaction (SMSI) is a phenomenon observed in supported metal catalyst systems in which reducible metal oxide supports can form overlayers over the surface of active metal nanoparticles (NPs) under a hydrogen (H2) environment at elevated temperatures. SMSI has been shown to affect catalyst performance in many reactions by changing the type and number of active sites on the catalyst surface. Laboratory methods for the analysis of SMSI at the nanoparticle‐ensemble level are lacking and mostly based on indirect evidence, such as gas chemisorption. Here, we demonstrate the possibility to detect and characterize SMSIs in Co/TiOx model catalysts using the laboratory X‐ray standing wave (XSW) technique for a large ensemble of NPs at the bulk scale. We designed a thermally stable MoNx/SiNx periodic multilayer to retain XSW generation after reduction with H2 gas at 600°C. The model catalyst system was synthesized here by deposition of a thin TiOx layer on top of the periodic multilayer, followed by Co NP deposition via spare ablation. A partial encapsulation of Co NPs by TiOx was identified by analyzing the change in Ti atomic distribution. This novel methodological approach can be extended to observe surface restructuring of model catalysts in situ at high temperature (up to 1000°C) and pressure (≤3 mbar), and can also be relevant for fundamental studies in the thermal stability of membranes, as well as metallurgy. [ABSTRACT FROM AUTHOR]

Efforts to develop high-performance electrocatalysts for the hydrogen evolution reaction (HER) are of utmost importance in ensuring sustainable hydrogen production. The controllable fabrication of inexpensive, durable, and high-efficient HER catalysts still remains a great challenge. Herein, we introduce a universal strategy aiming to achieve rapid synthesis of highly active hydrogen evolution catalysts using a controllable hydrogen insertion method and solvothermal process. Hydrogen vanadium bronze HxV2O5 was obtained through controlling the ethanol reaction rate in the oxidization process of hydrogen peroxide. Subsequently, the intermetallic PtCoVO supported on two-dimensional graphitic carbon nitride (g-C3N4) nanosheets was prepared by a solvothermal method at the oil/water interface. In terms of HER performance, PtCoVO/g-C3N4 demonstrates superior characteristics compared to PtCo/g-C3N4 and PtCoV/g-C3N4. This superiority can be attributed to the notable influence of oxygen vacancies in HxV2O5 on the electrical properties of the catalyst. By adjusting the relative proportions of metal atoms in the PtCoVO/g-C3N4 nanomaterials, the PtCoVO/g-C3N4 nanocomposites show significant HER overpotential of η10 = 92 mV, a Tafel slope of 65.21 mV dec−1, and outstanding stability (a continuous test lasting 48 h). The nanoarchitecture of a g-C3N4-supported PtCoVO nanoalloy catalyst exhibits exceptional resistance to nanoparticle migration and corrosion, owing to the strong interaction between the metal nanoparticles and the g-C3N4 support. Pt, Co, and V simultaneous doping has been shown by Density Functional Theory (DFT) calculations to enhance the density of states (DOS) at the Fermi level. This augmentation leads to a higher charge density and a reduction in the adsorption energy of intermediates. [ABSTRACT FROM AUTHOR]

The binary metal oxide-based catalysts have been proven to exhibit superior catalytic performances than their single metal oxides. As active supports, the physical and chemical properties of metal oxides would influence the chemical and electronic interactions with noble metal nanoparticles. By precise control of the composition and structure of metal oxides, the synergistic interaction between noble metals and transition metal oxides is expected to be realized. Herein, a novel hierarchical structured mCeO2 NR/Mn3O4/Pt catalysts were designed for low-temperature toluene combustion. The mCeO2 NR/Mn3O4 composites were fabricated by a simple and effective two-step sequential hydrothermal synthesis approach. After subsequent loading of Pt nanoparticles over mCeO2 NR/Mn3O4 by impregnation and reduction methods, the mCeO2 NR/Mn3O4/Pt catalysts with hierarchical structure were successively synthesized. The catalytical performances of the catalyst were evaluated by the toluene oxidation reaction. It was observed that the catalytic activities of the catalysts were closely related with the contents of Pt and Mn3O4, and mCeO2 NR/Mn3O4/Pt with 2.1% Mn and 0.45% Pt exhibited the greatest catalytic activity (T95 = 165 °C) toward the oxidation of toluene. The apparent activation energy for toluene oxidation with mCeO2 NR/Mn3O4/Pt (2.1% Mn) was as low as 35.3 kJ/mol. The improvement of the catalytical performance was due to the synergistic effect between CeO2 and Mn3O4 that led to the increase of oxygen vacancies and the enhancement of redox capacity, and the good dispersion of Pt active sites over the mCeO2 NR/Mn3O4. [ABSTRACT FROM AUTHOR]

Bismuth oxide (Bi2O3) nanoparticles are synthesized and evaluated for their function as materials for solar cells. Bi2O3 solution is inexpensively produced from the Nigella sativa seeds using a green synthetic method. The synthesized Bi2O3 solution is deposited by droplet casting method, and the synthesized nanofilm is dried at 80°C. Subsequently, diagnostic tests such as UV–VIS, XRD, and FTIR are performed on the Bi2O3/glass thin films. By means of the SEM, EDS, AFM, and I–V characteristics in dark and under illumination, the optical and structural characteristics of Bi2O3- nanoparticle films are investigated to determine the optical energy gap and crystalline material. X-ray diffraction reveals the presence of a tetragonal crystal system in the phase. The estimated band-gap energy Eg is approximately Eg1 = 3.6 eV, and FTIR analysis shows the degree of infrared absorption as a function of wavelength to demonstrate the presence of functional groups in bismuth-oxide molecules from Bi–O bonds. SEM–EDS morphology studies examine the occurrence of nanocrystals of various shapes and sizes. Finally, as a bulk heterojunction device, the I–V performance of the solar cell (Ag/Bi2O3/PSi/Si/Ag) deserves attention, and a fill factor FF= 48 is found for a solar-cell efficiency of 2.8%, ideality factor β= 1.35, characterization resistance RCH = 175 Ω, and the parallel resistance = 25.14 Ω·s. This cheap nanoparticle material could be an ideal candidate for future energy applications. [ABSTRACT FROM AUTHOR]

In this communication, we report cement composites containing Fe2O3 (iron oxide), TiO2 (titanium dioxide), SiO2 (silicon dioxide) and Cu (copper) nanoparticles added to ordinary portland cement (OPC) in various wt.%. Compressive strength measurements on the OPC-Fe2O3, OPC-TiO2, OPC-SiO2 and OPC-Cu samples are carried out systematically at the standard curing ages of 3, 7, 14 and 28 days, which show significant improvement in the mechanical strength at the optimum dose (wt.%) of nanoparticles. Highest increase in the compressive strength (33%) and flexural strength (20%) is seen for OPC-Fe2O3 (3 wt.% Fe2O3) at a curing age of 28 days. Studies on the OPC-TiO2, OPC-SiO2 and OPC-Cu composites show improvement in mechanical strength compared to that of reference OPC. Increase in mechanical strength is a result of faster and better cement hydration product (C-S-H gel) caused by the availability of higher active surface area of added nanoparticles. X-ray diffraction studies show the presence of C-S-H gel phase in the oxide-cement composites. Thermal treatment on OPC-Fe2O3 composites shows drastic degradation of compressive strength beyond 100 °C due to microcrack formation. Based on the compressive strength with optimum dose, we have carried out smart photocatalytic dye degradation (rhodamine-6G) studies on all the composites. OPC composites ground powder re-dispersed in de-ionized water and ultrasonicated before ultraviolet-visible dye degradation studies. The studies show faster dye degradation for all the composites compared to reference OPC. Highest degradation rate (~ 2.5 time) is obtained with OPC-Fe2O3 composite. Our studies show that these multifunctional oxide-cement composites can be used for dye degradation producing cleaner environment without loss of mechanical strength prerequisite for building application. [ABSTRACT FROM AUTHOR]

The concept of heat transport over a flat stretching surface for the inclusion of two unlike types of metal and oxide nanoparticles in a solvent water to investigate the role of hybrid nanofluid. The inclusion of Darcy–Forchheimer inertial drag over an elongating surface embedding in a porous medium enriches the flow behavior. However, the main attraction of the proposed investigation is the implementation of the Mintsa model conductivity combined with convective boundary condition that boosts up the thermophysical model. The suitable choice of similarity rules is useful for the transformation of governing equations into its non-dimensional form, and further traditional Runge–Kutta fourth-order method associated with shooting is employed to solve the flow profiles. The characteristics of controlling parameters on the flow phenomena along with the rate coefficients are deployed via graphs and tables. This investigation gives comparative results with earlier studies in particular cases. The important outcomes of the proposed investigation are: The augmented particle concentration favors in enhancing the fluid temperature in the permeable medium, whereas drag opposes the velocity profile significantly. [ABSTRACT FROM AUTHOR]

Porous nanoparticles integrating the advantages of porosity and structural coherence typically possess numerous active sites confined on their surfaces. In this study, porous Co3O4, Fe2O3 and Fe3O4 nanoparticles are synthesised by one-step pyrolysis from metal–organic frameworks (MIL-101 (Fe) and ZIF-67 (Co)) to test the performance of CO oxidation. The prepared porous nanoparticles have uniform and stable porous structures without obvious shrinkage and structural collapse. The best catalytic performance was achieved by the porous Co3O4 nanoparticles, which reached 100% CO conversion at 130 °C without any decay in catalytic activity after 48 h of reaction. DRIFTS results present the mechanism of the CO oxidation by porous Co3O4 nanoparticle catalysis. The excellent catalytic activity of the porous Co3O4 nanoparticles is related to the large specific surface area and surface oxygen vacancies. This work provides a design approach for synthesizing other porous metal oxide nanoparticles and has reference value in the field of CO oxidation. [ABSTRACT FROM AUTHOR]

Introduction: Nanoparticles (NPs) are of great interest in the design of various drugs due to their high surface-to-volume ratio, which result from their unique physicochemical properties. Because of the importance of examining the interactions between newly designed particles with different targets in the case of various diseases, techniques for examining the interactions between these particles with different targets, many of which are proteins, are now very common. Methods: In this study, the interactions between metal oxide nanoparticles (MONPs) covered with a carbon layer (Ag2O3, CdO, CuO, Fe2O3, FeO, MgO, MnO, and ZnO NPs) and standard drugs related to the targets of Cancer and bacterial infections were investigated using the molecular docking technique with AutoDock 4.2.6 software tool. Finally, the PRO TOX-II online tool was used to compare the toxicity (LD50) and molecular weight of these MONPs to standard drugs. Results: According to the data obtained from the semi flexible molecular docking process, MgO and Fe2O3 NPs performed better than standard drugs in several cases. MONPs typically have a lower 50% lethal dose (LD50) and a higher molecular weight than standard drugs. MONPs have shown a minor difference in binding energy for different targets in three diseases, which probably can be attributed to the specific physicochemical and pharmacophoric properties of MONPs. Conclusion: The toxicity of MONPs is one of the major challenges in the development of drugs based on them. According to the results of these molecular docking studies, MgO and Fe2O3 NPs had the highest efficiency among the investigated MONPs. [ABSTRACT FROM AUTHOR]

The objective of this study is to synthesize biologically derived CuO, Ag, and Gd2O3 polymetallic nanoparticles (NPs) using Justicia adhatoda bark extract. These nanoparticles were meticulously prepared and characterized through a comprehensive array of spectral analyses, including UV-Visible, FTIR, SEM, EDX, XRD, and thermal studies. UV-Vis spectroscopy revealed distinct absorption peaks in the 200-300 nm range, indicative of the presence of metal oxide nanoparticles. FTIR studies elucidated the interactions between bioorganic compounds and the synthesized NPs. SEM and XRD analyses provided insights into the crystallinity, crystal structure, and morphologies of the nanoparticles. Thermal properties, such as decomposition rates and transition energies, were examined via TGA/DTA. Notably, the PNs exhibited enhanced photocatalytic activity against methylene blue (MB) compared to individual NPs. Additionally, they demonstrated potent antibacterial effects against human pathogens and remarkable antimalarial activity against Aedes aegypti across various concentrations. The novelty of this work lies in the utilization of Justicia adhatoda bark extract for the green synthesis of multifunctional PNs with enhanced properties for diverse applications. [ABSTRACT FROM AUTHOR]

The oxidative C-C cleavage of a C18 substrate is an important transformation in synthetic organic chemistry, facilitating the synthesis of valuable C8-C9 acids widely used in many industries. Through a comparative analysis of the catalytic and physicochemical properties of catalysts, comprising mono- (Pd or Au) and bimetallic (PdAu) nanoparticles deposited on oxides, oxyhydroxides and graphite-like carbon material Sibunit (Cp), it was shown that the efficiency of the catalyst in the oxidative cleavage of 9,10-dihydroxystearic acid relies on the nature of the active component, the support and the average size of metal nanoparticles (NPs). The dependency of 9,10-DSA conversion on the average size of metal NPs shows the structural sensitivity of the oxidative cleavage reaction. Notably, catalysts with an average size of gold particles less than 3 nm exhibit the highest activity. The nature of the active component and the support material are crucial factors determining the process selectivity. Among the catalysts studied, the most effective for the oxidative cleavage of 9,10-DSA is a material based on Au NPs deposited on Cp. [ABSTRACT FROM AUTHOR]

This research paper explores the field of nanobiotechnology, focusing on the design, characterisation, and potential dermal applications of metal oxide nanoparticles (MONPs). ZnO and FeO NPs exhibit distinctive properties that are valuable in dermato‐cosmetic applications and transdermal drug delivery. This study investigates Cannabidiol (CBD) as a capping agent for MONPs synthesis. Employing microwave‐assisted techniques, MONPs were synthesised using either CBD or polyvinylpyrrolidone (PVP) as capping agents. The TEM, SEM, FTIR, and XRD characterisation results confirmed the successful formation of CBD‐capped ZnO and FeO NPs exhibiting an average particle size of 90 and 76 nm, respectively. The cytotoxicity of CBD‐capped MONPs was evaluated on HaCaT cells over a concentration range of 100 to 6.25 μg/mL, which revealed that CBD‐capped ZnO NPs exerted a cytotoxic effect on HaCaT cells (IC50 85.34±1.17 μg/mL). In contrast, CBD‐capped FeO NPs and PVP‐capped MONPs exhibited negligible cytotoxicity (IC50 >100 μg/mL). TEM analysis revealed a noticeable structural alteration of ZnO NPs in the supplemented cell culture medium, which could contribute to enhanced NP uptake, thereby explaining the more pronounced cytotoxic effect of ZnO NPs. Therefore, the disparity in cytotoxic responses can be attributed to the protein coating adhering to the NPs surface in a biological medium. [ABSTRACT FROM AUTHOR]

People are continuously exposed to electromagnetic waves emitted by mobile phones, base stations, computers, household electrical appliances, and nearby devices. Shielding against electromagnetic radiation is of great importance to avoid potential adverse effects on human health. This study addresses the development of electromagnetic shielding paints containing magnetic metal oxide nanoparticles. Magnetic metal oxide nanoparticles with a spinel ferrite structure, namely Fe3O4, CoFe2O4, and SnFe2O4, were synthesized using the co‐precipitation method. Their structural, morphological, and magnetic properties were characterized through FTIR, XRD, TEM, and VSM measurements. Electromagnetic shielding efficacy was assessed within the 3.5–12.5 GHz frequency range using waveguide measurements. Notably, pure magnetic metal oxide nanoparticles exhibited limited shielding efficiency, but incorporating conductive materials like multi‐walled carbon nanotubes improved the efficacy. Optimization studies, involved adjusting the nanoparticle‐to‐carbon nanotube ratios and coating thickness, demonstrated the best shielding to be with 50 : 10 [MFe2O4:PEG]:mwcnt ratio (M : Fe, Co, Sn) and 0.720 mm thickness, achieving up to 99 % of radiation shielding. The subsequent incorporation of the optimized magnetic composites into a water‐based wall paint at a 1 : 2 weight ratio demonstrated their effectiveness in shielding, successfully blocking 84 % of incoming radiation. [ABSTRACT FROM AUTHOR]

Polymers reinforced with metal oxide nanoparticles exhibit interesting possibilities from an application point of view due to the homogeneous distribution of nanoparticles and superior thermal and mechanical properties. In the present work, silicon dioxide (SiO2), zirconium dioxide (ZrO2), and zinc oxide (ZnO) nanoparticles were prepared by the microwave hydrothermal method, and polymer nanocomposites based on them were processed in polyvinyl alcohol (PVA) matrix. The size of the SiO2, ZrO2, and ZnO nanoparticles is around 80 nm, 44 nm, and 95.71 nm, respectively. The thermal decomposition behavior of pure PVA and nanocomposites was studied using thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). In the case, of nanocomposites, at 50% weight loss, the temperature was shifted by nearly 80°C compared to the pure PVA. Furthermore, the SiO2 doped nanocomposites showed a three-stage temperature decomposition in the DSC spectra. [ABSTRACT FROM AUTHOR]

This study synthesizes magnetic iron oxide nanoparticles from agro-waste sweet pepper extract, exploring their potential as antioxidant additives and in food preservation. Iron (III) chloride hexahydrate is the precursor, with sweet pepper extract as both a reducing and capping agent at pH 7.5. Characterization techniques, including microscopy and spectroscopy, analyze the sweet pepper extract-magnetic iron oxide nanoparticles. Antioxidant capacities against 2,2-diphenyl-1-picrylhydrazyl are assessed, incorporating nanoparticles into banana-based bioplastic for grape preservation. Microscopy reveals cubic and quasi-spherical structures, and spectroscopy confirms functional groups, including Fe–O bonds. X-ray diffraction identifies cubic and monoclinic magnetite with a monoclinic hematite presence. Sweet pepper extract exhibits 100% inhibitory activity in 20 min, while sweet pepper extract-magnetic iron oxide nanoparticles show an IC50 of 128.1 µg/mL. Furthermore, these nanoparticles, stabilized with banana-based bioplastic, effectively preserve grapes, resulting in a 27.4% lower weight loss rate after 144 h compared to the control group (34.6%). This pioneering study encourages institutional research into the natural antioxidant properties of agro-waste sweet pepper combined with magnetic iron and other metal oxide nanoparticles, offering sustainable solutions for nanopackaging and food preservation. Current research focuses on refining experimental parameters and investigating diverse applications for sweet pepper extract-magnetic iron oxide nanoparticles in varied contexts. [ABSTRACT FROM AUTHOR]

Owing to their remarkable properties, gold nanoparticles are applied in diverse fields, including catalysis, electronics, energy conversion and sensors. However, for catalytic applications of colloidal gold nanoparticles, the trade-off between their reactivity and stability is a significant concern. Here we report a universal approach for preparing stable and reactive colloidal small (~3 nm) gold nanoparticles by using multi-dentate polyoxometalates as protecting agents in non-polar solvents. These nanoparticles exhibit exceptional stability even under conditions of high concentration, long-term storage, heating and addition of bases. Moreover, they display excellent catalytic performance in various oxidation reactions of organic substrates using molecular oxygen as the sole oxidant. Our findings highlight the ability of inorganic multi-dentate ligands with structural stability and robust steric and electronic effects to confer stability and reactivity upon gold nanoparticles. This approach can be extended to prepare metal nanoparticles other than gold, enabling the design of novel nanomaterials with promising applications. For catalytic nanoparticles there is often a trade-off between stability and activity. Here the authors report a route to ultra-stable and catalytically active colloidal small (~3 nm) gold nanoparticles using multi-dentate polyoxometalates as protecting agents in nonpolar solvents. [ABSTRACT FROM AUTHOR]

Metal and metal oxide nanoparticles (NPs) embedded in glass matrixes exhibit special optical, electrical, or magnetic properties. Despite various approaches of encapsulating NPs in different kinds of glasses to prepare functional composite materials, there still exist challenges in fabricating efficiency and performance for silica glass made by traditional methods, such as sol–gel or melt quenching. Herein, the authors report a facile way to fabricate metal oxide NP‐doped silica glass by digital light processing (DLP) 3D printing technology for the first time. Different from common ion doping in silica glass, metal acetylacetonates that can be thermally decomposed to corresponding metal oxides innocuously, are chosen as a general precursor. Then, the representative nickel(II) acetylacetonate is introduced during the 3D printing process. The subsequent heat treatment generates a homogeneous distribution of NiO NPs in silica glass and it also exhibits optical nonlinear effect. The results provide a facile method for developing functional metal oxide‐doped glasses as well as the freeform fabrication of optoelectronic devices based on them. [ABSTRACT FROM AUTHOR]

The conjugation of DNA molecules with metal or metal-containing nanoparticles (M/MC NPs) has resulted in a number of new hybrid materials, enabling a diverse range of novel biological applications in nanomaterial assembly, biosensor development, and drug/gene delivery. In such materials, the molecular recognition, gene therapeutic, and structure-directing functions of DNA molecules are coupled with M/MC NPs. In turn, the M/MC NPs have optical, catalytic, pore structure, or photodynamic/photothermal properties, which are beneficial for sensing, theranostic, and drug loading applications. This review focuses on the different DNA functionalization protocols available for M/MC NPs, including gold NPs, upconversion NPs, metal–organic frameworks, metal oxide NPs and quantum dots. The biological applications of DNA-functionalized M/MC NPs in the treatment or diagnosis of cancers are discussed in detail. [ABSTRACT FROM AUTHOR]

Globally, cardiovascular diseases (CVDs) are the leading cause of death and disability. While there are many therapeutic alternatives available for the management of CVDs, the majority of classic therapeutic strategies were found to be ineffective at stopping or significantly/additionally slowing the progression of these diseases, or they had unfavorable side effects. Numerous metal-based nanoparticles (NPs) have been created to overcome these limitations, demonstrating encouraging possibilities in the treatment of CVDs due to advancements in nanotechnology. Metallic nanomaterials, including gold, silver, and iron, come in various shapes, sizes, and geometries. Metallic NPs are generally smaller and have more specialized physical, chemical, and biological properties. Metal-based NPs may come in various forms, such as nanoshells, nanorods, and nanospheres, and they have been studied the most. Massive potential applications for these metal nanomaterial structures include supporting molecular imaging, serving as drug delivery systems, enhancing radiation-based anticancer therapy, supplying photothermal transforming effects for thermal therapy, and being compounds with bactericidal, fungicidal, and antiviral qualities that may be helpful for cardiovascular diseases. In this context, the present paper aims to review the applications of relevant metal and metal oxide nanoparticles in CVDs, creating an up-to-date framework that aids researchers in developing more efficient treatment strategies. [ABSTRACT FROM AUTHOR]

Periodontitis, one of the most prevalent dental diseases, causes the loss of bone and gum tissue that hold teeth in place. Several bacteria, commonly present in clinically healthy oral cavities, may induce and perpetuate periodontitis when their concentration rises in the gingival sulcus. Antibacterial effect against various Gram-negative and Gram-positive bacteria, including pathogenic and drug-resistant ones, has been shown for several distinct transient metal and metal oxide NPs. Therefore, NPs may be used in biomedicine to treat periodontal problems and in nanotechnology to inhibit the development of microorganisms. Instead of using harmful chemicals or energy-intensive machinery, biosynthesis of metal and metal oxide nanoparticles (NPs) has been suggested. To produce metal and metal oxide NPs, the ideal technique is "Green" synthesis because of its low toxicity and safety for human health and the environment. Gold NPs (AuNPs) appear to be less toxic to mammalian cells than other nanometals because their antibacterial activity is not dependent on reactive oxygen species (ROS). AgNPs also possess chemical stability, catalytic activity, and superior electrical and thermal conductivity, to name a few of their other advantageous characteristics. It was observed that zinc oxide (ZnO) NPs and copper (Cu) NPs exhibited discernible inhibitory effects against gram-positive and gram-negative bacterial strains, respectively. ZnO NPs demonstrated bactericidal activity against the microorganisms responsible for periodontitis. Medications containing magnetic NPs are highly effective against multidrug-resistant bacterial and fungal infections. The titanium dioxide (TiO2) NPs are implicated in elevating salivary peroxidase activity in individuals diagnosed with chronic periodontitis. Furthermore, specific metallic NPs have the potential to enhance the antimicrobial efficacy of periodontitis treatments when combined. Therefore, these NPs, as well as their oxide NPs, are only some of the metals and metal oxides that have been synthesized in environmentally friendly ways and shown to have therapeutic benefits against periodontitis. [ABSTRACT FROM AUTHOR]

The exponential growth of electronic waste (e-waste) has raised significant environmental concerns, with projections indicating a surge to 74.7 million metric tons of e-waste generated by 2030. Waste printed circuit boards (WPCBs), constituting approximately 10% of all e-waste, are particularly intriguing due to their high content of valuable metals and rare earth elements. However, the presence of hazardous elements necessitates sustainable recycling strategies. This review explores innovative approaches to sustainable metal nanoparticle synthesis from WPCBs. Efficient metal recovery from WPCBs begins with disassembly and the utilization of advanced equipment for optimal separation. Various pretreatment techniques, including selective leaching and magnetic separation, enhance metal recovery efficiency. Green recovery systems such as biohydrometallurgy offer eco-friendly alternatives, with high selectivity. Converting metal ions into nanoparticles involves concentration and transformation methods like chemical precipitation, electrowinning, and dialysis. These methods are vital for transforming recovered metal ions into valuable nanoparticles, promoting sustainable resource utilization and eco-friendly e-waste recycling. Sustainable green synthesis methods utilizing natural sources, including microorganisms and plants, are discussed, with a focus on their applications in producing well-defined nanoparticles. Nanoparticles derived from WPCBs find valuable applications in drug delivery, microelectronics, antimicrobial materials, environmental remediation, diagnostics, catalysis, agriculture, etc. They contribute to eco-friendly wastewater treatment, photocatalysis, protective coatings, and biomedicine. The important implications of this review lie in its identification of sustainable metal nanoparticle synthesis from WPCBs as a pivotal solution to e-waste environmental concerns, paving the way for eco-friendly recycling practices and the supply of valuable materials for diverse industrial applications. [ABSTRACT FROM AUTHOR]