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Computational modeling of plasmon-mediated molecular photophysical and photochemical behaviors can help us better understand and tune the bound molecular properties and reactivity and make better decisions to design and control nanostructures. However, computational investigations of coupled plasmon–molecule systems are challenging due to the lack of accurate and efficient protocols to simulate these systems. Here, we present a hybrid scheme by combining the real-time time-dependent density functional theory (RT-TDDFT) approach with the time-domain frequency dependent fluctuating charge (TD-ωFQ) model. At first, we transform ωFQ in the frequency-domain, an atomistic electromagnetic model for the plasmonic response of plasmonic metal nanoparticles (PMNPs), into the time-domain and derive its equation-of-motion formulation. The TD-ωFQ introduces the nonequilibrium plasmonic response of PMNPs and atomistic interactions to the electronic excitation of the quantum mechanical (QM) region. Then, we combine TD-ωFQ with RT-TDDFT. The derived RT-TDDFT/TD-ωFQ scheme allows us to effectively simulate the plasmon-mediated "real-time" electronic dynamics and even the coupled electron–nuclear dynamics by combining them with the nuclear dynamics approaches. As a first application of the RT-TDDFT/TD-ωFQ method, we study the nonradiative decay rate and plasmon-enhanced absorption spectra of two small molecules in the proximity of sodium MNPs. Thanks to the atomistic nature of the ωFQ model, the edge effect of MNP on absorption enhancement has also been investigated and unveiled. [ABSTRACT FROM AUTHOR]

The influence of a dielectric layer with an embedded 2D array of metal nanoparticles on the spectral characteristics of a distributed Bragg reflector is theoretically studied and numerically validated. A significant dependence of the reflectivity of the hybrid structure on the location of the nanoparticle array relative to the maxima and minima of the optical field in the surface dielectric layer is demonstrated. It is found that the application of a dilute ensemble of nanoparticles (the interparticle distance is from 2 to 5 times larger than the nanoparticle size) in the region of high optical field localization makes it possible to obtain a total suppression of reflection in the photonic bandgap range of distributed Bragg reflector. Contrariwise, if the optical field is almost zero at the nanoparticle array location, its impact on the scattered light is negligible, that is, the resonant nanoparticles are masked by a highly reflective photonic structure. The target wavelength can be tuned inside the photonic bandgap range by adjusting the shape of nanoparticles and interparticle distance in the array. [ABSTRACT FROM AUTHOR]

InN holds great promise for a wide range of applications, including broadband optical devices, high-frequency electronic devices, and serving as a substrate for highly sensitive gas detectors and efficient catalysts. Nevertheless, production of high-quality InN thin films through epitaxy has remained a significant challenge. This is primarily due to complexities arising from the low dissociation temperature and the high N2 equilibrium pressure of InN, which lead to formation of numerous nitrogen vacancies and a propensity to generate indium metal nanoparticles. Efficacy of the indium bilayer pre-deposition method for InN film growth has been established in prior studies. In this work, we introduce a specialized hydrogen insertion method to further enhance nitridation of the indium bilayer. The corresponding kinetic mechanism has been demonstrated through theoretical simulations and practical epitaxy experiments, leading to the development of an optimized hydrogen insertion process. This research represents a substantial improvement over existing InN epitaxial methods that involve control of the indium bilayer and introduces a novel mechanism for enhancing InN heteroepitaxy. [ABSTRACT FROM AUTHOR]

Electromagnetic shielding is a critical function in various technologies, which is ideally achieved using a metal that reflects all incident radiation below its plasma frequency. Using high-resolution finite difference frequency domain simulations at microwave/RF frequencies, we show that the same efficacy can be achieved using a disordered collection of metal nanoparticles embedded in a flexible material. The mechanism underlying the reflection in the composite material is wave localization, disallowing the propagation of radiation up to the plasma frequency of the metal that constitutes the particles. We realize such a biopolymer composite using DNA–CTMA (deoxyribonucleic acid–cetyltrimethylammonium complex) as a support structure for Ag nanoparticles. This biopolymer composite exhibits an extremely high shielding effectiveness, close to that of a metal slab, because of Anderson localization of the electromagnetic waves. [ABSTRACT FROM AUTHOR]

Strong light–matter interactions significantly modify the optical properties of molecules in the vicinity of plasmonic metal nanoparticles. Since the dimension of the plasmonic cavity approaches that of the molecules, it is critical to explicitly describe the nanoparticle junctions. In this work, we use the discrete interaction model/quantum mechanical (DIM/QM) method to model the coupling between the plasmonic near-field and molecular excited states. DIM/QM is a combined electrodynamics/quantum mechanical model that uses an atomistic description of the nanoparticle. We extend the DIM/QM method to include the local field effects in the sum-over-state formalism of time-dependent density functional theory. As a test of the method, we study the interactions between small organic chromophores and metal nanoparticles. In particular, we examine how the inclusion of multiple electronic transitions and intermolecular interactions modify the coupling between molecules and nanoparticles. Using the sum-over-state formalism of DIM/QM, we show that two-state models break down when the plasmon excitation is detuned from the molecular excitations. To gain further insight, we compare the simple coupled-dipole model (CDM) with the DIM/QM model. We find that CDM works well for simple systems but fails when going beyond the single molecule or single nanoparticle cases. We also find that the coupling depends strongly on the site of the nanoparticle in which the chromophore couples to. Our work suggests the importance of explicitly describing the cavity to capture the atomistic level local field environment in which the molecule strongly couples to. [ABSTRACT FROM AUTHOR]

Supported metallic nanoparticles play a central role in catalysis. However, predictive modeling is particularly challenging due to the structural and dynamic complexity of the nanoparticle and its interface with the support, given that the sizes of interest are often well beyond those accessible via traditional ab initio methods. With recent advances in machine learning, it is now feasible to perform MD simulations with potentials retaining near-density-functional theory (DFT) accuracy, which can elucidate the growth and relaxation of supported metal nanoparticles, as well as reactions on those catalysts, at temperatures and time scales approaching those relevant to experiments. Furthermore, the surfaces of the support materials can also be modeled realistically through simulated annealing to include effects such as defects and amorphous structures. We study the adsorption of fluorine atoms on ceria and silica supported palladium nanoparticles using machine learning potential trained by DFT data using the DeePMD framework. We show defects on ceria and Pd/ceria interfaces are crucial for the initial adsorption of fluorine, while the interplay between Pd and ceria and the reverse oxygen migration from ceria to Pd control spillover of fluorine from Pd to ceria at later stages. In contrast, silica supports do not induce fluorine spillover from Pd particles. [ABSTRACT FROM AUTHOR]

The recent transition to H2-based energy storage demands reliable H2 sensors that allow for easy, fast, and reliable detection of leaks. Conventional H2 detectors are based on the changes of physical properties of H2 probes induced by subsurface H-atoms to a material such as electrical conductivity. Herein, we report on highly reactive gasochromic H2 detectors based on the adsorption of H2 on the material surface. We prepared supraparticles (SPs) containing different types of noble metal nanoparticles (NPs), silica NPs, and the dye resazurin by spray-drying and tested their performance for H2 detection. The material undergoes a distinct color change due to the hydrogenation of the purple resazurin to pink resorufin and, finally, colorless hydroresorufin. The stepwise transition is fast and visible to the naked eye. To further improve the performance of the sensor, we tested the reactivity of SPs with different catalytically active NPs by means of in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). We show that the choice of the NP catalyst has a pronounced effect on the response of the H2 indicator. In addition, we demonstrate that the performance depends on the size of the NPs. These effects are attributed to the availability of reactive H-atoms on the NP surface. Among the materials studied, Pt-containing SPs gave the best results for H2 detection. [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]

A multiscale nanoengineering strategy, simultaneously including metal nanoparticle-atomized pathway and metal-organic framework-derived approach, is developed to realize the anchoring of atomic and nanosized transition-metal species in N-doped hierarchically tubular porous carbon for high-performance oxygen reduction and evolution reactions. [Display omitted] • A multiscale nanoengineering strategy, simultaneously including metal-organic framework-derived approach and metal nanoparticle-atomized pathway, to realize the anchoring of atomic and nanosized Fe/Co species on N-doped hierarchically tubular porous carbon substrate. • Fe/Co nanoparticles and single atoms are respectively utilized for accelerating OER and ORR, endowing the obtained material with a small OER/ORR potential gap of 0.684 V. • When the obtained material is used in the air electrode, 260 mW cm-2 of peak power density for liquid-state Zn-air battery, 110 mW cm-2 of peak power density for solid-state Zn-air battery, and 1000 charge-discharge cycles without decay are realized. The development of cost-effective, high-activity and stable catalysts to accelerate the sluggish kinetics of cathodic oxygen reduction/evolution reactions (ORR/OER) plays a critical part in commercialization application of rechargeable Zn-air batteries (RZABs). Herein, a multiscale nanoengineering strategy is developed to simultaneously stabilize Co-doped Fe nanoparticles originated from metal-organic framework-derived approach and atomic Fe/Co sites derived from metal nanoparticle-atomized way on N-doped hierarchically tubular porous carbon substrate. Thereinto, metal nanoparticles and single atoms are respectively used to expedite the OER and ORR. Consequently, the final material is acted as an oxygen electrode catalyst, displaying 0.684 V of OER/ORR potential gap, 260 mW cm-2 of peak power density for liquid-state RZAB, 110 mW cm-2 of peak power density for solid-state RZAB, and 1000 charge-discharge cycles without decay, which confirms great potential for energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

Radiation chemistry enables the synthesis of colloidal nanoparticles without chemical reducing agents, yielding metal nanoparticles via simple and direct processes. Aliphatic alcohols are widely used to promote the formation of nanoparticles in radiolytic synthesis by inhibiting the reoxidation of these metal nanoparticles by scavenging hydroxyl radicals. However, the role of the scavenger has been limited to simply accelerating the formation of the nanoparticles without altering their nature. Herein, the role of radical scavengers is investigated in determining the type of metal nanoparticles formed, with the scavenger concentration playing a crucial role. It is found that the addition of isopropyl alcohol controls the formation of hexagonal close‐packed (hcp) palladium hydride (PdHx) nanoparticles that are previously synthesized for the first time via radiation chemistry by increasing the concentrations of hydrated electrons and hydrogen radicals. This discovery reveals a more active role for radical scavengers in radiolytic syntheses, and this strategy can be used for the cost‐effective mass production of hcp PdHx nanoparticles. [ABSTRACT FROM AUTHOR]

Excessive use of azithromycin (AZM) is associated with resistance and negative impacts on the environment. Therefore, this study aimed to develop an electrochemical sensor for AZM. The screen‐printed carbon electrode (SPCE) modified with boron‐doped diamond nanoparticle (BDDNP) and reduced‐graphene oxide (rGO) was successfully applied to measure the AZM concentration. The morphology of the modified electrode was characterized by scanning electron microscopy‐energy dispersive X‐ray (SEM‐EDX). Furthermore, the effect of electrochemical parameters, such as signal per background, scan rate, and selectivity was determined. The results showed that under optimum conditions, the plot of AZM demonstrated linearity in the range of 30–100 μM with a limit of detection (LOD) at 1.6 μM. The repeatability and recovery were also investigated, and the sensor was applied to real samples obtained from hospital wastewater. A remarkable 93.27 % recovery rate and excellent precision were recorded with an %RSD of 2.41 %. This study underscores the potential of SPCE modified with rGO/BDDNP for accurate and reliable measurement of AZM levels, showcasing great applicability in addressing the challenges associated with monitoring AZM in various environmental settings. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) have gained significant attention due to their multifunctional properties and broad applications in various fields. In this study, we present a novel and sustainable approach for the synthesis of silver nanoparticles (AgNPs) using waste materials, dried banana pith extract (BPE) and rice water. The synthesised AgNPs exhibit a size of 43 nm and zeta potential of −24.1 mV. A maximum temperature rise of 4°C with an efficiency of 41% is achieved within a short time by the photothermal activity. The qualitative colorimetric detection of Fe3+ and its quantitative spectroscopic detection are achieved in a linear detection range of 20–80 μM and with a limit of detection of 8.5 μM. The sensing mechanism is explained in terms of cooperative binding of Fe3+ ions to BPE-AgNPs. A homogeneous, flexible and stable AgNP-rice starch gel is formed. The work offers environmentally conscious nanomaterials for diverse applications. [ABSTRACT FROM AUTHOR]

Study of nanoparticles has attracted the immense attention of researchers because of their wide applications in the medicine, chemical industries, and biotechnology. This paper highlights that plants and microbes can be a source of bio-compounds in nanoparticle synthesis in place of toxic chemicals. As this is an environmentally friendly approach following the principles of green synthesis which is cheap and is not toxic. Both sources provide antioxidant, anticancer, and antimicrobial properties which hold great importance in the manufacturing of NPs. This review aims to bring together the diversity of synthesized metallic nanoparticles mediated by plant extracts, fungi, algae, bacteria and yeasts. All the mentioned bio-resources contain biomolecule which includes protein and enzyme which serves the twin action of both reduction and capping of the synthesized nanoparticles. The synthesized NPs are characterized by using UV-visible spectrometry, FT-IR, XRD, TEM, SEM and EDX. Also, the biomedical application of the synthesized NPs is explored in the treatment of cancer. [ABSTRACT FROM AUTHOR]

Recently, metal nanoparticles synthesized by bio-fabrication methods were being used for various life-saving treatments. In our present study, AuNPs were fabricated using aqueous Panicum Maximum (P. Maximum) leaf extract. The analysis of UV–Visible spectrophotometer indicated the excitation of the formed AuNPs, specifically, a distinct SPR band positioned nearly at 530 nm. The formation of AuNPs with 45–50-nm size range was confirmed by TEM. Also, SAED pattern was utilized to characterize single crystalline nature of the biofabricated AuNPs. Further, the anticancer effects of synthesized AuNPs were studied against HepG2 cells. After incubating HepG2 cells with AuNPs, the amount of cytochrome c, CASP 9/CASP 8/CASP 3/BAX expression level, formation of ROS, and cell viability were analyzed. Outcomes of our study showed a dose determined cytotoxicity and half inhibitory concentration (IC50) of 75 μg/mL for the synthesized AuNPs. Cytotoxicity of AuNPs was accompanied by cell apoptosis and ROS induction in cell line of HepG2. Based on our results, AuNPs could have potential for development of new drugs for therapy of liver hepatocellular carcinoma in nursing care. [ABSTRACT FROM AUTHOR]

The detection and quantitation of bisphenol A (BPA) in the environment and food products has been a subject of considerable interest. BPA, a diphenylmethane derivative is a well-known industrial raw material with wide range of applications. It is a well-known endocrine disruptor and acts as an estrogen mimic. BPA is an environmental health concern and its accumulation in hydro-geological cycles is a matter of serious ecological peril. This review basically assesses various chemically modified electrodes composed of diverse components that have been employed to recognize BPA in different matrices. Electrochemical sensors prepared using graphene materials in combination with metals and polymers for selective detection of BPA have been discussed extensively. The emphasis is on detection of BPA in various samples encountered in routine use such as plastic bottles, receipts, baby feed bottles, milk samples, mineralized water, tissue paper, DVDs, and others. Although research in this field is in the exploratory stage, deeper insights into fundamental studies of sensing systems, fast analysis of real samples and validation of sensors are some of the factors that need major impetus. It is expected that chemically modified electrode-based sensing systems will soon take over as a viable option for monitoring diverse pollutants. [ABSTRACT FROM AUTHOR]

Two-step electrosynthesis of nanocomposites of bimetallic PdCu and PdAu nanoparticles (NPs) with iron(II), aluminum(III), zinc(II), copper(I), and titanium(IV) oxide−hydroxides was carried out in the presence of stabilizer cetyltrimethylammonium chloride (CTAC). In the first step, efficient syntheses of Fe, Al, Zn, Cu, and Ti oxide−hydroxides were carried out by reducing dissolved oxygen or methylviologen and generating metal ions by dissolution the corresponding metal anodes. In the second step, syntheses of bimetallic PdCu and PdAu NPs were proceeded by methylviologen (MV2+)-mediated electroreduction of equimolar concentration of Cu(II), Pd(II), and Au(I) in the presence of CTAC and obtained oxide−hydroxides. The results of the syntheses were nanocomposites of mainly spherical MNPs stabilized with CTAC on the surface of oxide−hydroxides with an average size of 2 to 10 nm, but the PdAu@CTAC/Cu2O nanocomposite showed formation of two NPs types with sizes 7 ± 2 nm (Pd) and 24 ± 10 nm (Au). X-ray powder diffraction data showed the absence of metal crystallites in almost all samples with PdCu due to the amorphous phase, and the presence of bimetallic crystallites with sizes ranging from 1 to 15 nm in PdAu composites. In the test reaction of p-nitrophenol reduction all the tested nanocomposites exhibited catalytic activity. [ABSTRACT FROM AUTHOR]

The bismuth-layered ferroelectric (BLF) oxides are promising photocatalysts due to their wide band gap, photo-coupled ferro properties, Pb-Free composition, and excellent chemical stability. In this study, polycrystalline SrBi 4 Ti 4 O 15 (SBT) is used as the target photocatalyst, and its photocatalytic performance was evaluated in terms of Rhodamine-B dye degradation under UV light. Moreover, the influence of metal deposition (Ag, Zn, Fe, and Bi) was also explored. The powders of SBT and its metal-decorated derivatives were synthesized and structural, compositional, and optical properties were studied in detail using XRD, XPS, EDS, FTIR, UV–Vis, Raman, and PL spectroscopy. The pristine SBT powders showed 19% photodegradation after 60 min of exposure to UV radiation. Metal nanoparticles deposited on the surface of the SBT were found to improve photocatalytic capacity and a nearly threefold increase (53%) in degradation rate was achieved for Bi-decorated SBT. The rate constant and the turnover frequency are 0.01336 min - 1 and 13.2 × 10 - 3 mol Rh - B mol metal h - 1 , respectively. The degradation was observed to follow a Langmuir–Hinshelwood (LH) model, indicating that the process is first order. [ABSTRACT FROM AUTHOR]

For accurate patient identification and treatment, early-stage disease diagnosis is particularly important. However, a lack of patient compliance with the current diagnostic techniques prevents prompt diagnosis, making the creation of noninvasive diagnostic tools essential. Breath analysis, one of the most promising noninvasive diagnostic techniques that has also attracted a lot of research interest recently, finds gas analytes like exhaled volatile organic compounds (VOCs) and inorganic gases that are thought to be significant biomarkers for a variety of disease types. The common technique for the detection of biomarkers in breath involves spectrometric-based measurements. Despite their precision and accuracy to detect a low concentration of exhaled breath, these techniques have some disadvantages such as lack of portability, being expensive, high power demand, and requiring trained staff to operate them. Consequently, recent interest in nanotechnology has accelerated the development of new chemosensors, sensing techniques, and enhanced the performance and sensitivity of existing chemosensors in the rapidly evolving field of biosensing. Chemosensors made with nanotechnology can identify diseases and monitor treatment outcomes. This review paper aims to present a current overview of the major chemosensor categories investigated for applications in disease diagnosis via the detection of exhaled gas analytes and to emphasize the significance of nanomaterials. Various nanomaterial-based chemosensors, prepared with several metal and metal oxide nanoparticles for detections of different types of volatile organic compound biomarkers. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) composited on metal–organic frameworks (MOFs) can generate valuable materials (MNP/MOF) possessing good physical, chemical, and biological properties. The preparation of novel MNP/MOF followed by exploration of their applications has inspired great investigational enthusiasm. In this paper, Ni, Co and Ni–Co bimetallic MNP/MOF catalysts derived from MOFs were prepared by controlled pyrolysis, and then characterized by TGA, FTIR, XRD, BET, SEM, XPS and H2-TPD, which showed that pyrolysis under H2 (reported typically under an inert atmosphere) and the addition of Co to Ni–MOF could form Ni–Co alloy MOFs with not only a relatively complete MOFs structure but good dispersion of metal nanoparticles. In order to disclose their potential for utilization, specifically, the activity tests of the prepared novel MNP/MOF materials were conducted on the hydrogenation of toluene towards methylcyclohexane. The results confirmed that the Ni1Co2/MOF-325 catalyst obtained by pyrolysis of Ni1Co2–MOF under H2 at 325 °C had high activity and good stability for the hydrogenation of toluene, showing excellent prospect as a hydrogenation catalyst. [ABSTRACT FROM AUTHOR]

Harnessing solar energy to produce hydrogen through semiconductor-mediated photocatalytic water splitting is a promising avenue to address the challenges of energy scarcity and environmental degradation. Ever since Fujishima and Honda's groundbreaking work in photocatalytic water splitting, titanium dioxide (TiO2) has garnered significant interest as a semiconductor photocatalyst, prized for its non-toxicity, affordability, superior photocatalytic activity, and robust chemical stability. Nonetheless, the efficacy of solar energy conversion is hampered by TiO2's wide bandgap and the swift recombination of photogenerated carriers. In pursuit of enhancing TiO2's photocatalytic prowess, a panoply of modification techniques has been explored over recent years. This work provides an extensive review of the strategies employed to augment TiO2's performance in photocatalytic hydrogen production, with a special emphasis on foreign dopant incorporation. Firstly, we delve into metal doping as a key tactic to boost TiO2's capacity for efficient hydrogen generation via water splitting. We elaborate on the premise that metal doping introduces discrete energy states within TiO2's bandgap, thereby elevating its visible light photocatalytic activity. Following that, we evaluate the role of metal nanoparticles in modifying TiO2, hailed as one of the most effective strategies. Metal nanoparticles, serving as both photosensitizers and co-catalysts, display a pronounced affinity for visible light absorption and enhance the segregation and conveyance of photogenerated charge carriers, leading to remarkable photocatalytic outcomes. Furthermore, we consolidate perspectives on the nonmetal doping of TiO2, which tailors the material to harness visible light more efficiently and bolsters the separation and transfer of photogenerated carriers. The incorporation of various anions is summarized for their potential to propel TiO2's photocatalytic capabilities. This review aspires to compile contemporary insights on ion-doped TiO2, propelling the efficacy of photocatalytic hydrogen evolution and anticipating forthcoming advancements. Our work aims to furnish an informative scaffold for crafting advanced TiO2-based photocatalysts tailored for water-splitting applications. [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]

This study evaluated the efficacy of phytogenic silver and zinc nanoparticles in improving heat resilience in various wheat varieties. The silver and zinc nanoparticles were synthesized using plant leaf extract and characterized using various techniques. Four wheat varieties (DBW187, Black Wheat, DBW 50, and PBW 621) were subjected to field trials. The random block design was used, and nanoparticles in different concentrations were applied at various growth stages and morphologically, and yield parameters were recorded. UV–vis spectroscopy spectral analysis showed peaks for Ag nanoparticles at 420 nm wavelength and Zn nanoparticles at 240 and 350 nm wavelength, depicting the preliminary confirmation of nanoparticle synthesis. Electron microscopic analysis (TEM and SEM) provided morphological insights and confirmed synthesis of fine-sized particle mostly in a range between 10 and 60 nm. Energy dispersive x-ray analysis confirmed the elemental composition of the synthesized nanoparticles, with Ag and Zn elements detected in their respective samples. It also confirmed the oxide nature of synthesized ZnNPs. Dynamic light scattering analysis provided size distribution profiles, indicating average sizes of approximately 61.8 nm for Ag nanoparticles and 46.5 nm for Zn nanoparticles. The concentrations of Ag and Zn nanoparticles in the samples were found to be 196.3 ppm and 115.14 ppm, respectively, through atomic absorption spectroscopic analysis. Fourier transform infrared spectroscopy analysis revealed characteristic functional groups present in the nanoparticles. The results of field experiments established that Ag nanoparticles at 75 ppm concentration exhibited the most significant enhancements in plant growth. Conversely, Zn nanoparticles at a 100 ppm concentration demonstrated the most substantial improvements in the growth and yield of heat-stressed wheat varieties. The study concludes that optimized concentrations of silver and zinc nanoparticles can effectively improve heat stress resilience in wheat. These findings are promising to enhance abiotic stress resilience in crops. [ABSTRACT FROM AUTHOR]

Supported‐metal catalysts, pivotal for industrial applications, have their catalytic properties affected by metal‐support interactions (MSIs), which notably influence both their electronic and geometric characteristics. Therefore, understanding internal and external factors that influence MSIs is crucial for the rational design of catalysts. Our minireview focuses on the effects of the gas environment on the MSIs, particularly the morphological changes in metal nanoparticles, the migrating behavior of reducible supports (strong metal‐support interaction), and the compositional rearrangement of the catalysts (reactive metal‐support interaction). Future directions are suggested to elucidate the fundamental aspects of gas environment induced structural reconstruction of catalysts, including the quantitative analysis of dynamic behavior of both the surface and interface, atomic‐level insights into the structures of the metal, support, and interface under pertinent conditions through advanced in situ/operando characterization, and the in situ manipulation of structural reconstruction. [ABSTRACT FROM AUTHOR]

Owing to well‐defined structure as well as easy synthesis and modification, metal‐organic frameworks (MOFs) have emerged as promising catalysts for tandem reactions. In this article, we aim to summarize the development of multifunctional MOFs, including mixed metal MOFs, MOFs that are synergistically catalyzed by metal nodes and organic linkers, MOFs loaded with metal nanoparticles, etc, as heterogenous catalysts for tandem reactions over the past five years. This concept briefly discusses on present challenges, future trends, and prospects of multifunctional MOFs catalysts in tandem reactions. [ABSTRACT FROM AUTHOR]

The upgrading of a benzyl-type alcohols was explored via an orthogonal tandem sequence comprised of a first oxidative step producing the corresponding aldehydes, and a subsequent reductive amination to achieve both secondary and tertiary amines. To the scope, acetonitrile (ACN) was used as a solvent and a source/precursor of reactant amines, and different heterogeneous catalysts based on Rh and Mo, were designed as mono- and bi-metallic systems in the form of metal nanoparticles dispersed on a chitinderived N-doped carbons. A parametric analysis carried out separately for the oxidation and the reductive amination allowed to choose the best performant catalyst for both the reactions of the tandem process. A one-pot two-step protocol was implemented accordingly: as an example, benzyl alcohol was quantitatively and selectively oxidised to benzaldehyde (>99%) which in turn, was converted to N-benzylethanamine (66%) or N-benzyl-N-ethylethanamine (60%) in the presence of [Rh(5%)-N/C--Mo (5%)]-N/C or [Rh(3%)-N/C--Mo(5%)]-N/C as catalysts, respectively. The tandem sequence proved successful also for other bio-based benzyl-type alcohols that afforded the corresponding secondary/tertiary amines in yields up to 53--93%. Overall, the study proved the viability of an innovative method aimed not only at process intensification for multistep synthesis, but also at the valorization of substrates (alcohols) and biopolymers (chitin) derived from biomass. [ABSTRACT FROM AUTHOR]

The theoretically infinite compositional space of high-entropy alloys (HEAs) and their novel properties and applications have attracted significant attention from a broader research community. The successful synthesis of high-quality single-phase HEA nanoparticles represents a crucial step in fully unlocking the potential of this new class of materials to drive innovations. This review analyzes the various methods reported in the literature to identify their commonalities and dissimilarities, which allows categorizing these methods into five general strategies. Physical minimization of HEA metals into HEA nanoparticles through cryo-milling represents the typical top–down strategy. The counter bottom–up strategy requires the simultaneous generation and precipitation of metal atoms of different elements on growing nanoparticles. Depending on the metal atom generation process, there are four synthesis strategies: vaporization of metals, burst reduction of metal precursors, thermal shock-induced reduction of metal precursors, and solvothermal reduction of metal precursors. Comparisons among the methods within each strategy, along with discussions, provide insights and guidance for achieving the robust synthesis of HEA nanoparticles. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) are emerging as idealized model catalysts for imprecise metal nanoparticles to unveil their structure-activity relationship. However, the directional synthesis of robust metal NCs with accessible catalytic active sites remains a great challenge. In this work, we achieved bulky carboranealkynyl-protected copper NCs, the monomer Cu13·3PF6 and nido-carboranealkynyl bridged dimer Cu26·4PF6, with fair stability as well as accessible open metal sites step by step through external ligand shell modification and metal-core evolution. Both Cu13·3PF6 and Cu26·4PF6 demonstrate remarkable catalytic activity and selectivity in electrocatalytic nitrate (NO3 -) reduction to NH3 reaction, with the dimer Cu26·4PF6 displaying superior performance. The mechanism of this catalytic reaction was elucidated through theoretical computations in conjunction with in situ FTIR spectra. This study not only provides strategies for accessing desired copper NC catalysts but also establishes a platform to uncover the structure-activity relationship of copper NCs. [ABSTRACT FROM AUTHOR]

Metal nanoparticles incorporated into carbon nanostructures have tremendous applications in the field of nanosensors and other technologies. Herein, a nanohybrid of reduced graphene oxide modified with silver and/or palladium nanoparticles (Ag/Pd/rGO) was prepared by impregnation of Pd and Ag into the rGO platform and deposited on a glass carbon electrode. Palladium and silver nanoparticles improve the stability and durability of the sensor platform by preventing the agglomeration of graphene oxide sheets and providing chemical stability against environmental factors. This ensures long‐term reliability and repeatability of the sensor performance. The morphologies and microstructures of the as‐prepared nanohybrid were characterized by X‐ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, UV–visible and infrared spectroscopy. The average crystallite size of PdAgNPs was found to be between 12 and 15 nm and demonstrated good dispersion across reduced graphene oxide sheets with high‐loading capacities. Thorough investigation of the electrochemical properties of the nanomaterial surfaces through cyclic voltammetry (CV) experiments, revealed distinct redox peaks for Ag+/Ag0 and Pd2+/Pd0 processes and demonstrated the excellent electrochemical properties of the prepared nanocomposites. The rGO‐PdAgNPs‐GCE had a diffusion coefficient value of 1.14×10−14 cm2 s−1 which is acceptable for electrochemical sensors as it is indicative of a fast response time and enhanced sensitivity to changes in gas concentration. The results obtained through thorough characterizations contributes to the novelty of the research by offering a deeper understanding of the material properties and the potential of the nanohybrid material for a broad application scope. [ABSTRACT FROM AUTHOR]

Freshwater contamination by metals can come from a variety of sources and be damaging to wildlife, alter landscapes, and impact human health. Metals removal is desirable not only for improving water quality and preventing adverse effects but also for metals collection and recycling. Nanoadsorption of metals is economically feasible and nanoscale materials exhibit a high surface-area-to-volume ratio that is promising for high adsorption and reactivity. However, the extraordinarily small dimensions of these materials allow them to maneuver biological systems, and combined with high reactivity, this translocation can result in toxicity. In this work, nanoparticles (NPs) composed of a magnetite core coated in hydroxyapatite (HA) and functionalized for adsorption with titanium dioxide (TiHAMNPs) were synthesized. The magnetic core enabled NP retrieval, while HA enhanced adsorption and minimized toxicity. Here, synthesis and characterization are presented, revealing a stable NP structure exhibiting a near neutral surface charge. Results of adsorption studies showed that as compared to silica-coated magnetite nanoparticles (SiMNPs), traditionally used for this application, TiHAMNPs exhibited significantly higher adsorption (43.28% more Cu removal) after 24 h. The equilibrium rate constant for the adsorption of Cu by TiHAMNPs was 0.0003 g/(min*mg) and TiHAMNP adsorption data indicated that TiHAMNPs adsorb metals in a monolayer at the particle surface with a maximum capacity of 2.8 mmol/g. Metabolic and toxicity assays showed TiHAMNPs were highly biocompatible as compared to SiMNPs. This work also explores rare earth element (REE) separation applications of TiHAMNPs, finding that TiHAMNPs may provide a promising alternative for REE retrieval and/or separation. [ABSTRACT FROM AUTHOR]

α‐Fe2O3 with suitable band structure, good chemical stability, and easy preparation, is a potential photoanode material. However, the key to enhance the performance of α‐Fe2O3 photoanode is to improve the transport characteristics of bulk carriers. It is expected to form a Schottky barrier to improve the carrier separation efficiency by embedding metal nanoparticles into the matrix, but the process is still challenging. Herein, a strategy of forming the Schottky barrier is shown to improve bulk carrier transport dynamics by embedding laser‐generated Pt nanocrystals in α‐Fe2O3 photoanode, which achieves photocurrent densities of up to 1.16 mA cm−2 at 1.23 VRHE (from original 0.21 mA cm−2). This work provides another way to promote the carrier transfer and separation of α‐Fe2O3, which is of great significance to improve the photoelectrochemical water splitting performance. [ABSTRACT FROM AUTHOR]

We recently found that polyvinylpyrrolidone (PVP)-protected metal nanoparticles dispersed in water/butanol mixture spontaneously float to the air/water interface and form two-dimensional assemblies due to classical surface excess theory and Rayleigh–Bénard–Marangoni convection induced by butanol evaporation. In this study, we found that by leveraging this principle, a unique structure is formed where hetero gold nanospheres (AuNPs)/gold nanostars (AuNSs) complexes are dispersed within AuNP two-dimensional assemblies, obtained from a mixture of polyvinylpyrrolidone-protected AuNPs and AuNSs that interact electrostatically with the AuNPs. These structures were believed to form as a result of AuNPs/AuNSs complexes formed in the water/butanol mixture floating to the air/water interface and being incorporated into the growth of AuNP two-dimensional assemblies. These structures were obtained by optimizing the amount of mixed AuNSs, with excessive addition resulting in the formation of random three-dimensional network structures. The AuNP assemblies dispersed with AuNPs/AuNSs complexes exhibited significantly higher Raman (surface-enhanced resonance Raman scattering: SERRS) activity compared to simple AuNP assemblies, while the three-dimensional network structure did not show significant SERRS activity enhancement. These results demonstrate the excellent SERRS activity of AuNP two-dimensional assemblies dispersed with hetero AuNPs/AuNSs complexes. [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]

This study investigated the inhibition effect of nanoscale silver–copper particle (20 nm) against Coriolus versicolor and Gloeophyllumtrabeum. Poplar wood samples (Populus L.) were vacuum-impregnated using aqueous nano-AgCu solutions at concentrations of 0.01 %, 0.02 %, 0.03 %, 0.05 %, 0.075 %, and 0.1 %. Alkaline copper quaternary (ACQ, 0.1 %), boric acid (0.2 %) and untreated control group (CK) were employed for comparisons. Decay resistance and leachability were studied. The anti-fungi effects were compared between nano-AgCu, nano-Ag, Ag+ (silver nitrate), Cu2+ (copper nitrate), and a composite of Ag+–Cu2+. Nano-AgCu particle exhibited effective resistance to fungi after 12 weeks of exposure. The threshold retention of the nano-AgCu against C. versicolor and G. trabeum on poplar wood was 0.19 kg m−3 and 0.62 kg m−3, respectively. The silver–copper nanoparticles demonstrated excellent leach resistance, and the inhibition effect was retained after leaching. The nano-AgCu particle provided better antifungal effects than single ions or metal nanoparticles. This study illustrates the potential of using nano-AgCu particle as an efficient wood preservative compared to commercial water-soluble preservatives. [ABSTRACT FROM AUTHOR]

The phenomenon of strong metal‐support interaction (SMSI) observed in supported metal catalysts, usually accompanied by the formation of the encapsulation layer on metal nanoparticles, has attracted extensive research attention due to its significance in heterogeneous catalysis. Notably, great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy (TEM), along with an enhanced comprehension of the underlying mechanisms governing SMSI formation. This emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions. A brief perspective about the use of in situ TEM for further study of SMSI is also presented, showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts. [ABSTRACT FROM AUTHOR]

Three different types of carbon screen-printed electrodes consisting of mesoporous carbon (MC), carbon nanofibers (CNF), and single-walled carbon nanotubes (SWCNT) were used as carbon supports for deposition of Ag, in the absence of reductant in the plating solution. The SPEs were characterized by Raman spectroscopy and show marked differences in their structure. To drive the metal deposition, the carbon supports were potentiostatically pre-treated in supporting electrolyte. The metal deposition occurred in AgNO3 solution and resulted in the formation of homogeneously distributed metal nanoparticles with type and amount depending on both the potential used in the pre-treatment step and the structure of the carbon electrodes. Larger metal amounts and higher particle densities (in the 109 cm−2 range) together with smaller particle mean sizes (in the 40- to 60-nm range) were obtained by using more negative potential for the pre-treatment. A further way to influence the characteristics of the metal deposit was based on double or triple consecutive pre-treatment/deposition cycles. The obtained results are discussed in view of the possible sources of electron supply, necessary for the formation of the metal particles on the carbon carrying substrates. [ABSTRACT FROM AUTHOR]

High‐temperature plasmonics deals with optically active nanostructures that can withstand high temperatures. A conventional approach relying on standalone noble metal nanoparticles fails to deliver refractory plasmonic nanomaterials, and an alternative route envisions metal nitrides. The main challenge remains the development of advanced synthesis techniques and the insight into thermal stability under real‐life application conditions. Here, hafnium nitride nanoparticles (HfN NPs) can be produced by gas aggregation using reactive magnetron sputtering, a technique with a small environmental footprint are shown. As‐deposited NPs are of 10 nm mean size and consist of stoichiometric, crystalline fcc HfN. They are characterized by optical absorption below 500 nm caused by interband transitions and in the red/near‐infrared (NIR) region due to intraband transitions and localized surface plasmon resonance (LSPR). The optical response can be engineered by tuning the NP composition as predicted by finite‐difference time‐domain (FDTD) calculations. Going beyond the state‐of‐the‐art, the HfN NP thermal stability is focued under ultrahigh vacuum (UHV) and in air. During UHV annealing to 850 °C, the NPs retain their morphology, chemical and optical properties, which makes them attractive in space mission and other applications. During air annealing to 800 °C, HfN NPs remain stable until 250 °C, which sets a limit for air‐mediated use. [ABSTRACT FROM AUTHOR]

The necessity for the creation of safe, dependable, biocompatible, and efficient methods to make nanoparticles drives an increasing number of researchers to consider using biological systems as potential eco-friendly nanofactories. Fungi have an innate ability to reduce and oxidize metal ions into metal oxide nanoparticles, thus behaving as nanofactories. In the present study, Trichoderma harzianum was used to prepare ZnO nanoparticles (ZnO NPS). ZnO NPS showed a peak at 370 nm upon testing using UV spectrophotometer and percentages of zinc(72.0±0.2 %) and oxygen(28.0 ±0.3) upon analysis using Edx with an irregular shape, 16.5 nm size and characterized XRD pattern. Soymilk as well as the prepared ZnONPs were investigated either separately or in their mixture (1:1) for their antibacterial and anti-tumor effects. The mixture showed a promising antibacterial impact on Enterococcus faecalis (ATCC29212) and Escherichia coli (ATCC25922) which was confirmed using a transmission electron microscope. ZnONPs mixed with soymilk showed a promising anti-tumor action towards human colorectal adenocarcinoma cell line Caco-2 through boosting apoptotic rate, which was detected by flow cytometry. The current report highlights the possibility of mixing eco-friendly biosynthesized nanoparticles with natural products to enhance their biomedical impact with minimal toxicity as possible innovative pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Their health industry is facing challenges due to a rise in mortality rates brought on by various multi‐drug‐resistant bacterial strains. As a result, new and improvedantibacterial drugs are urgently needed. Similarly, when some unwanted foreign pathogensenter the cellular premises to disturb its homeostasis, inflammation develops as an immune reaction. However, these immune responses also become a double‐edged sword when the inflammatory reaction lasts for a long time, and pain is also linked to inflammatory responses. Inflammation and pain are both signs of tissue injury. Pain is,by definition, an unpleasant experience that ultimately interferes with their normalwell‐being. Hence, bacterial infection, inflammation, and pain need medical assistance to maintain homeostasis. Conventional medicines possess so many repercussive effects, which then demand a replacement with a less toxic and more efficient modern drug. In their review article, for the first time, they present recent advancements in biomedical applications such as the antimicrobial, anti‐inflammatory, and analgesic properties of noble metal nanoparticles. Noble metals have limited availability in the earth's crust. Hence, their physicochemical characterizations and applications are greatly limited. Still, there are some interesting research findings that offer a significant ray of hope for the health sector all over the world. [ABSTRACT FROM AUTHOR]

Bio-based polymers are attracting increasing interest as alternatives to harmful and environmentally concerning non-biodegradable fossil-based products. In particular, bio-based polymers may be employed as ligands for the preparation of metal nanoparticles (M(0)NPs). In this study, chitosan (CS) was used for the stabilization of Ru(0) and Rh(0) metal nanoparticles (MNPs), prepared by simply mixing RhCl3 × 3H2O or RuCl3 with an aqueous solution of CS, followed by NaBH4 reduction. The formation of M(0)NPs-CS was confirmed by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Analysis (EDX), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). Their size was estimated to be below 40 nm for Rh(0)-CS and 10nm for Ru(0)-CS by SEM analysis. M(0)NPs-CS were employed for the hydrogenation of (E)-cinnamic aldehyde and levulinic acid. Easy recovery by liquid-liquid extraction made it possible to separate the catalyst from the reaction products. Recycling experiments demonstrated that M(0)NPs-CS were highly efficient up to four times in the best hydrogenation conditions. The data found in this study show that CS is an excellent ligand for the stabilization of Rh(0) and Ru(0) nanoparticles, allowing the production of some of the most efficient, selective and recyclable hydrogenation catalysts known in the literature. [ABSTRACT FROM AUTHOR]

4-nitrophenol (4-NP) is a frequently encountered toxic phenolic organic pollutant in water. It is important to develop a simple method to treat 4-NP. Small and monodispersed gold nanoparticles often have good catalytic performance of 4-NP. Hemoglobin (Hb) is a kind of common and important protein in organisms. Herein, highly biocompatible bovine hemoglobin-stabilized gold nanoparticles (Aun-Hb NPs) were synthesized using hemoglobin as a biological template. Then, the size, zeta potential, and composition of Aun-Hb NPs were investigated by transmission electron microscopy, dynamic light scattering, and X-ray photoelectron spectroscopy. The Aun-Hb NPs with small gold nanoparticles of about 1.4–2.4 nm had good catalytic capabilities in reducing 4-NP to form 4-aminophenol. Au20-Hb NPs demonstrated superior catalytic efficiency in the reduction of 4-NP when compared to other nanoparticles. Moreover, as-synthesized Au20-Hb NPs exhibited excellent biocompatibility through the MTT experiment. The method of preparation of gold nanoparticles offers one way to prepare metal nanoparticles for good potential catalytic applications of gold nanoparticles. [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]

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 IrRh@C ZIF-8 catalysts capable of oxidizing H 2 , CO, or a combination of the two is fabricated through the secondary high temperature annealing. Benefiting from the closely located single atom sites to the nanoparticles, CO on the metal nanoparticles could be efficiently removed, thus conferring the catalysts with excellent H 2 oxidation performance in CO presence that has not been possible before. This work opens up a new avenue to conquer the formidable poisoning issue of PEMFCs. [Display omitted] Nanosized Pt catalysts are the catalyst-of-choice for proton exchange membrane fuel cell (PEMFC) anode, but are limited by their extreme sensitivity to CO in parts per million (ppm) level, thereby making the use of ultrapure H 2 a prerequisite to ensure acceptable performance. Herein, we confront the CO poisoning issue by bringing the Ir/Rh single atom sites to synergistically working with their metallic counterparts. In presence of 1000 ppm CO, the catalyst represents not only undisturbed H 2 oxidation reaction (HOR) catalytic behavior in electrochemical cell, but also unparalleled peak power density at 643 mW cm−2 in single cell, 27-fold in mass activity of the best PtRu/C catalysts available. Pre-poisoning experiments and surface-enhanced Raman scattering spectroscopy (SERS) and calculation results in combine suggest the presence of adjacent Ir/Rh single atom sites (SASs) to the nanoparticles (NPs) as the origin for this prominent catalytic behavior. The single sites not only exhibit superb CO oxidation performance by themselves, but can also scavenge the CO adsorbed on approximated NPs via supplying reactive OH* species. We open up a new route here to conquer the formidable CO poisoning issue through single atom and nanoparticle synergistic catalysis, and pave the way towards a more robust PEMFC future. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation technology has great potential in solving the global challenge of freshwater shortage. However, the selection of excellent photothermal conversion materials is a challenging task. To achieve efficient solar interface evaporation materials, we developed a new material loaded with Fe/Fe3C nanoparticles on mesoporous carbon hollow spheres (MCHSs). As an interfacial evaporation material, Fe/Fe3C@MCHS-x has an evaporation rate of 1.633 kg m−2 h−1 and an energy conversion efficiency of 94.17% (Fe/Fe3C@MCHS-2). The innovative introduction of magnetic particles into the evaporation unit allows the metal nanoparticles to absorb light at their resonance wavelength. This absorption leads to the excitation of electrons from the occupied state to the unoccupied state, and the diffusion of thermoelectrons leads to an increase of carriers, which makes the interface temperature rise rapidly. The composite material has a certain degree of organic pollution treatment capability along with high-efficiency water evaporation, which provides new ideas for interfacial evaporation material technology. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Localized surface plasmon resonance has been demonstrated to provide effective photophysical enhancement mechanisms in plasmonic photocatalysis. However, it remains highly challenging for distinct mechanisms to function in synergy for a collective gain in catalysis due to the lack of spatiotemporal control of their effect. Herein, the anisotropic plasmon resonance nature of Au nanorods was exploited to achieve distinct functionality towards synergistic photocatalysis. Photothermal and photochemical effects were enabled by the longitudinal and transverse plasmon resonance modes, respectively, and were enhanced by partial coating of silica nanoshells and epitaxial growth of a reactor component. Resonant excitation leads to a synergistic gain in photothermal‐mediated hot carrier‐driven hydrogen evolution catalysis. Our approach provides important design principles for plasmonic photocatalysts in achieving spatiotemporal modulation of distinct photophysical enhancement mechanisms. It also effectively broadens the sunlight response range and increases the efficacy of distinct plasmonic enhancement pathways towards solar energy harvesting and conversion. [ABSTRACT FROM AUTHOR]

The biogenic approach for the synthesis of metal nanoparticles provides an efficient eco-friendly alternative to chemical synthesis. This study presents a novel route for the biosynthesis of silver nanoparticles using aqueous sandalwood (SW) leaf extract as a source of reducing and capping agents under mild, room temperature synthesis conditions. The bioreduction of Ag+ to Ago nanoparticles (SW-AgNPs) was accompanied by the appearance of brown color, with surface plasmon resonance peak at 340-360 nm. SEM, TEM and AFM imaging confirm SW-AgNP's spherical shape with size range of 10-32 nm. DLS indicates a hydrodynamic size of 49.53 nm with predominant negative Zeta potential, which can contribute to the stability of the nanoparticles. FTIR analysis indicates involvement of sandalwood leaf derived polyphenols, proteins and lipids in the reduction and capping of SW-AgNPs. XRD determines the face-centered-cubic crystalline structure of SW-AgNPs, which is a key factor affecting biological functions of nanoparticles. This study is novel in using cell culture methodologies to evaluate effects of SW-AgNPs on proliferating cells originating from plants and human cancer. Exposure of groundnut calli cells to SW-AgNPs, resulted in enhanced proliferation leading to over 70% higher calli biomass over control, enhanced defense enzyme activities, and secretion of metabolites implicated in biotic stress resistance (Crotonyl isothiocyanate, Butyrolactone, 2-Hydroxy-gamma-butyrolactone, Maltol) and plant cell proliferation (dl-Threitol). MTT and NRU were performed to determine the cytotoxicity of nanoparticles on human cervical cancer cells. SW-AgNPs specifically inhibited cervical cell lines SiHa (IC50–2.65 ppm) and CaSki (IC50–9.49 ppm), indicating potential use in cancer treatment. The opposing effect of SW-AgNPs on cell proliferation of plant calli (enhanced cell proliferation) and human cancer cell lines (inhibition) are both beneficial and point to potential safe application of SW-AgNPs in plant cell culture, agriculture and in cancer treatment. [ABSTRACT FROM AUTHOR]

The current analysis deals with the physiological flow of hybrid nanofluid within an expanding and contracting vertical annulus embedding with a permeable medium. Additionally, in the free convective viscous flow, the impact of thermal radiation on the heat transport phenomenon is vital. The significance of this research lies in the utilization of Hamilton–Crosser thermal conductivity to investigate the behavior of nanoparticles with different shapes. In this study, both oxide nanoparticles like Al2O3 and metal nanoparticles like Ag are incorporated into the blood, which serves as the base fluid. This incorporation aims to enhance the performance of hybrid nanofluids in influencing flow phenomena. The proposed mathematical model designed for the above-mentioned constraints is solved analytically following the transformation into their corresponding non-dimensional form. The statistical behavior of the diversified parameters is presented graphically and the numerical results for the rate coefficients are deployed via table. Further, the important characteristics of the results are depicted as follows: the combined effect of the particle concentration used in hybrid nanofluid favors in reducing the fluid velocity greatly than that of nanofluid and pure fluid. [ABSTRACT FROM AUTHOR]