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The sluggish kinetics and thermodynamic stability associated with LiAlH 4 have posed significant obstacles to its practical application. Herein, we have designed a general method for preparing a series of hollow 3D flower-like composite, denoted as M-NC@TiO 2 (M = Ni, Co, Fe, Cu), which serve as highly efficient catalysts for the dehydrogenation of LiAlH 4. These composites feature TiO 2 hollow spheres as substrates to induce the growth of MOF nanosheets, leading to the regular arrangement of carbon nanosheets anchored with metal nanoparticles M on the TiO 2 sphere surface after calcination treatment. Evidently, M-NC@TiO 2 exerts a discernible enhancement on the dehydrogenation kinetics of LiAlH 4. LiAlH 4 -7wt% Ni-NC@TiO 2 system begins to release hydrogen at a notably lowered temperature of 56.3 °C, with a total amount of hydrogen released of 7.19 wt% before reaching 300 °C. Subsequent investigations showed that the enhanced hydrogen storage performance can be attributable to the in-situ formation of the metal compounds, the fine size and high dispersion of metallic nanoparticles, and the synergistic effect between TiO 2 and M nanoparticles. This work not only provides an effective general way to synthesize catalysts for improving the hydrogen storage performance of aluminum-based hydrogen storage materials, but also augments our understanding of hydrogen storage mechanisms. [ABSTRACT FROM AUTHOR]

Ta 2 O 5 /Pd hybrid microspheres were readily synthesized via a one-step thermal solution process employing a template composed of glucose carbon spheres, yielding a structure characterized by a rough and porous surface. This morphology offers an expanded contact area and increased sites for ethanol reactions of Ta 2 O 5 /Pd hybrid microspheres. At room temperature (25 °C), the Ta 2 O 5 /Pd hybrid microspheres exhibited responsiveness to ethanol concentrations ranging from 50 to 700 ppm, displaying a linear response pattern to a narrow concentration gradient of 90–120 ppm. The hybrid exhibited notable sensitivity, manifesting a response value of 5.1–100 ppm ethanol. In addition, they displayed less responsiveness to other VOCs gases, were minimally affected by humidity, and maintained gas-sensitive stability for 30 days, demonstrating excellent selectivity and long-term stability. Based on the fitting curve analysis, the material theoretically demonstrated the ability to detect ethanol at concentrations as low as 101 ppb. Ta 2 O 5 /Pd hybrid microspheres modified by glucose carbon sphere templates and noble metal nanoparticles are promising candidates for ethanol room temperature sensing, providing new insights into the development of room temperature sensing. [ABSTRACT FROM AUTHOR]

In recent years, magnetic metal nanoparticles (NPs)/carbon nanofibers (CNFs) composites have become very promising electromagnetic waves (EMWs) absorbers. However, how to achieve controllable growth of magnetic metals in CNFs is still an urgent problem to be solved. Herein, we reported a pore-confined strategy for constructing the porous Co/CoO/CNFs. By introducing different amounts of acetone (0.20 g, 0.30 g and 0.40 g) into the aqueous phase spinning solution to construct the porous structure, we achieved uniform distribution of Co/CoO NPs and ultimately obtained the porous Co/CoO/CNFs microwave absorbers (MAs) with excellent microwave absorption performance. Thanks to the excellent impedance matching and enhanced polarization loss, the porous Co/CoO/CNFs obtained the minimum reflection loss (RL) of −52.2 dB with a thickness of 3.0 mm, and the effective bandwidth (EBW) was 3.02 GHz when the acetone addition in the spinning solution was 0.30 g. Therefore, the pore-confined strategy proposed herein is conducive to the design of the MAs with excellent performance and low infilling rates based on CNFs. Furthermore, the porous structure of CNFs also improves the lightweight performance of the MAs. [ABSTRACT FROM AUTHOR]

• 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]

Global exploration of nanoparticles as nano-fertilizers/nano-fungicides to optimize crop production has attracted greater attention. Among metal oxide nano-formulations, the increasing application and discharge of copper oxide nanoparticles (CuO-NPs) into the environment requires urgent attention due to their toxic and stimulatory impact on plants, including vegetables. This study aimed at the bio-fabrication of CuO-NPs from Rosa indica petal extracts and to assess their nanotoxicity on germination and biological and biochemical growth of tomato plants. The morphological characterization of phytofabricated CuO-NPs by microscopic (SEM/TEM) and spectroscopic (XRD/FTIR) techniques revealed its nanostructure, spherical shape ranging in size between 23 and 47 nm exhibiting different functional groups. Furthermore, tomato-CuO-NPs interactions resulted in reduced germination percentage and plant biomass. At the biochemical level, the chlorophyll content decreased consistently, while malonaldehyde and proline content in tomato foliage enhanced substantially with increasing concentrations of CuO-NPs. Size, lycopene content (71 % reduction), and fruit quality (metabolites like sugars, amino acids, and organic acids) assessed by 1H NMR declined after CuO-NPs exposure in a dose-dependent manner. Further in situ experiments revealed deformation in a stomatal aperture in leaves and accumulation of CuO-NPs in roots, suggesting toxicity under SEM. In summation, this study highlights the toxicity of biosynthesized CuO-NPs to tomato plants paving the way to develop novel strategies to mitigate its toxicity to vegetable crops, particularly tomato under real field conditions. [Display omitted] • Copper oxide nanoparticles (CuO-NPs) exhibit toxic and stimulatory effects on plants. • Biogenic synthesized CuO-NPs from Rosa indica petal extract shows phytotoxicity to tomato plants. • Exposure to CuO-NPs reduces germination percentage, plant biomass, and fruit quality. • Metal oxide nanoparticles increase malondialdehyde and proline content after CuO-NPs exposure. • Strategies need to be developed to counteract nano-CuO toxicity. [ABSTRACT FROM AUTHOR]

The green synthesis of noble metal nanoparticles has gained a lot of interest in the area of nanotechnology, because of its high therapeutic properties. The present study focussed on the synthesis of the silver nanoparticles (Ag-NPs) using Ceropegia debilis leaf extract and characterized by various physio-chemical techniques and surface morphological studies. The prepared Ag-NPs exhibit a face-centred cubic structure, spherical morphology, and high purity as shown by XRD, SEM, and EDS analyses. The average size of the Ag-NPs was confirmed by TEM study as 18.6 ± 7.5 nm. The synthesized Ag-NPs show remarkable antioxidant activity of 72.1% compared to standard BHT 86.9%. Furthermore, Ag-NPs show remarkable cytotoxic properties against MCF 7 and A 549 cell line of 37.19% and 33.33%, respectively at 250 µg/mL. The antibacterial activity of Ag-NPs was investigated against the human pathogen and intestinal pathogen Staphylococcus aureus and Escherichia coli by agar disc diffusion method. Moreover, the synthesised Ag-NPs exhibit good antifungal properties against the fungal specimen Trichoderma viride assessed by well diffusion technique. In addition, Ag-NPs serve as an excellent nanocatalyst in the removal of toxic methylene blue dye (93.2%) from industrial wastewater under sunlight irradiation. [Display omitted] • Silver nanoparticles were synthesized by Ceropegia debilis extract. • SEM and TEM used for surface morphology and size determination. • Impressive anti-proliferative activity towards MCF 7 and A 549 were observed. • Effective nanocatalyst for the degradation of methylene blue dye. [ABSTRACT FROM AUTHOR]

Lung cancer remains a major global health problem with high mortality rates. Early diagnosis can significantly improve prognosis. Hence alternative diagnostic platforms facilitating rapid, noninvasive, point-of-care screening are needed. Nanomaterial-assisted electrochemical biosensors present a promising technology. Unique properties of nanomaterials like high electrical conductivity, catalytic activity, and large surface area enhance achieved detection limits and kinetics. Recent works have combined nanomaterials like graphene, metal nanoparticles and conducting polymers with recognition elements like antibodies and aptamers. Considerable progress has focused on improving analytical parameters including sensitivity, linear ranges, reproducibility and response times. Initial embodiments also demonstrate multiplexed detection, microfluidic integration and smartphone connectivity towards viable clinical practice. However considerable efforts on large sample size validation, standardization of testing protocols and viable commercialization pathways integrating regulatory guidelines and reimbursement ecosystem partnerships remain before such lab-on-chip platforms can enter mainstream and guide therapeutic interventions through affordable decentralized personalized monitoring. [ABSTRACT FROM AUTHOR]

Gram-negative bacteria Pseudomonas putida , Gram-positive Bacillus subtilis, and Staphylococcus aureus were utilized as test samples to evaluate the antibacterial characteristics of DD3-clay/MgO and DD3+38 wt% ZrO 2 -clay/MgO nanoparticles. The ceramic powders prepared by a thermal autoclave method are characterized before and after Mg addition by SEM, EDX, XRD, IR, UV–visible, and TEM in order to investigate microstructure, phase, and surface morphology. The results showed that after adding Mg, it led to the deformation of the crystal lattices of (mullite, zirconium silicate, and zirconium oxide) together with a decrease in particle size (75–103 nm) and a complete change in its shape from nanotube to nanospherical, as observed by SEM and TEM analyses. It also confirmed by UV–visible spectroscopy that the addition of Mg increases the absorbance accompanying a decrease in the energy gap of 1.91, 1.74, 1.73, and 1.43 eV corresponding to DD3, DD3Z, DD3/30 wt% Mg and DD3Z/30 wt% Mg respectively. The antibacterial mechanism is related to the size of the particles, the solvent used for powder dissolution, the nanoparticle's size when they come into touch with bacteria, and the generation of reactive oxygen species (ROS: ˙O 2 −, ˙OH, and H 2 O 2). It was observed that the anti-bacterial activity is enhanced with 10 wt% and 30 wt% of Mg added to a modified ceramic powder. Also, more O 2 − is formed on the surface of the prepared powder, which penetrates the bacterial cell and destroys it. The nanocomposite particles showed remarkable antibacterial activity when they were dissolved in DMSO compared to methanol and chloroform as organic solvents. The aim is to enrich knowledge on the antibacterial activities of metal nanoparticles (ZrSiO 4 and MgO) on three bacterial strains with different Grams due to their extensive involvement in the phenomena of contamination and infection encountered in the medical field. The synthesized nanoparticles have good antimicrobial activity against all strains tested. A maximum inhibition zone of 35 ± 0.2 mm was obtained with S. aureus , a zone of 23 ± 0.46 mm with P. putida and a zone of 27 ± 0.46 nm with B. subtilis for DD3/30 wt% Mg and an inhibition zone of 38 ± 0.93 mm, 26 ± 0.24 nm and 17 ± 0.33 nm was obtained with same strains for DD3Z/30 wt% Mg, respectively. [ABSTRACT FROM AUTHOR]

Biogenic combustion with Mellifera (Honey) capping produced ZnO, Ag-doped ZnO, and Fe-doped ZnO nanoparticles. The phase and crystal structure of metal oxide nanoparticles (MONPs) have been recorded through XRD spectrum. It confirms that the prepared metal oxides are within the nanoscale range. The average crystallite size of Fe-doped ZnO is 8.8 nm, smaller than ZnO and Ag-doped nanoparticles. The vibrational spectra of ZnO, Ag-doped ZnO, and Fe-doped ZnO nanoparticles confirm functional group stretching vibrational modes. The exterior surface morphology of all metal oxide nanoparticles was captured by FESEM. Metal oxide nanoparticle compositional analysis shows elemental presence, atomic, and weight %. The optical properties of metal oxide nanoparticles have been examined using UV–vis spectroscopy. The band gap energy of ZnO nanoparticles reduced from 2.68 eV to 1.74 eV under Fe doing and increased to 2.9 eV under Ag doing. Metal oxide thermal stability is also being investigated to determine how it affects ZnO nanoparticles. Fe-doped ZnO nanoparticles have greater sensor properties than other metal oxides due to their tiny size, band gap, and stability. Gas sensor behaviour of three metal oxide nanoparticles was examined in various accepts. It proves Fe-doped ZnO is a promising gas sensor material. [ABSTRACT FROM AUTHOR]

Herein we report the catalytic ethanol decomposition over cobalt catalyst synthesized using conventional solution combustion synthesis (SCS). The reaction pathway proposed in-situ DRIFT analysis shows that the decomposition reaction proceeds through the formation of surface ethoxy intermediates that transformed into acetates and aldehydes which further decompose to releases CH 4 , H 2 and CO 2 with some deposition of carbon on the catalyst surface. The catalytic reaction shows 100 % ethanol conversion at 420 °C, with high selectivity of H 2 in the output. The structural transformation of the catalyst and deposited carbon was analyzed using high-resolution transmission electron microscope (HRTEM). Presence of small Co nanoparticles (size <30 nm) surrounded with graphene and larger metal nanoparticles trapped inside MWCNTs was visible during a stability run over 50 h that motivates in proposing the reaction mechanism of the fluctuating metal nanoparticle along with carbon on the catalyst surface. Moreover, this work opens up the possibility of synthesizing highly dispersed Co nanoparticles in an efficient way without any complex experimental procedures and equipment that can further be used as effective catalysts in many industrial reactions. • Catalytic reaction shows 100 % ethanol conversion at 420 °C on cobalt catalyst. • Transformation on particle and carbon structure during stability run is seen. • Co nanoparticles between 10 and 30 nm with graphene layer were observed. • Metal nanoparticles trapped inside MWCNTs after 50 h of ethanol conversion. • Proposed mechanism describes the metal nanoparticle fluctuation with carbon structure. [ABSTRACT FROM AUTHOR]

Recently, two-dimensional systems have attracted considerable interest from scientists, due to their high H 2 storage capacity and excellent reversibility. In this context, by means of DFT computations, we predict a novel system known as boron carbide, which can be formed by replacing 50% carbon atoms with boron atoms in tetragonal-graphene. We investigate the hydrogen adsorption performance of pristine and functionalized t-B 4 C 4 sheets with the metals Li/Sc/Ti. Results indicate that metal-decorated t-B 4 C 4 exhibits significantly lower H 2 adsorption energies compared to pristine t-B 4 C 4. Moreover, the hydrogen storage capacities for Li/Sc/Ti@t-B 4 C 4 are 13.32%, 10.03% and 9.74% respectively. Furthermore, the desorption temperature exceeds the critical temperature of H 2. Based on activation energy, H 2 can migrate quickly on the t-B 4 C 4 sheet during the adsorption/desorption cycles. Our results indicate that t-B 4 C 4 functionalized with Li/Sc/Ti-metals can be an efficient material for hydrogen storage. • Based on DFT and AIMD, we predict a novel material known as t-B 4 C 4 monolayer for hydrogen storage. • Li/Sc/Ti-decoration improves the H 2 -storage performance on t-B 4 C 4 monolayer. • The wt%.H 2 for the Li/Ti/Sc-decorated t-B 4 C 4 are found to be 13.32, 10.03 and 9.74 wt%, respectively. • Desorption temperatures higher than hydrogen's critical point are found. • Hydrogen molecule can move quickly on the t-B 4 C 4 monolayer. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) takes advantage of greenhouse gases (CH 4 and CO 2) and mitigates their eco-environmental consequences. However, the biggest obstacle for DRM reactions has been the design of catalysts with high resistance to sintering and carbon deposition. In this paper, the embedded bimetallic nickel-cobalt@ silicalite-1 (S1) catalysts (NiCo@S1), with high resistance to sintering and lower carbon deposition, were prepared by grinding crystallization method. The physicochemical characterizations demonstrated that the embedded catalyst for NiCo@S1 could effectively control the size and dispersion of the active metal Ni–Co in the catalyst compared to the supported catalysts for 10Ni/SiO 2 and 10Ni/S1, which further enhance the interaction between the active metal phase and the carrier S1, and greatly minimize the amount of carbon accumulation on the catalysts. After being subjected to a reaction at 700 °C for 6 h, the 10Ni2.5Co@S1 exhibited a significant performance improvement. The instantaneous conversion rate of CH 4 increased from 63.17% to 86.39% (an increase of 23.22%), and the instantaneous conversion rate of CO 2 rose from 70.20% to 88.62% (an increase of 18.42%). Additionally, carbon deposition reduced from 14.58% to 0.82% (a decrease of 13.76%). Therefore, the conceptual design provided a new perspective for designing Ni-based dry reforming catalysts. • An industry-friendly grinding crystallization method has been introduced. • The grinding crystallization method can effectively promote the dispersion of active components、enhance metal-support interaction and prevent the migration of metal nanoparticles and their agglomeration, avoiding sintering, and thus reducing carbon deposition. • 10Ni2.5Co@S1 catalyst showed excellent performance in dry reforming of methane reactions. [ABSTRACT FROM AUTHOR]

Metal oxides are recognized as exemplary materials for photocatalytic dye degradation attributed to their unique characteristics such as tunable electronic structure, prolonged stability, and cost-effectiveness. However, the wide band gap inherent to most of these materials often limits their light absorption to the ultraviolet (UV) region. Consequently, the doping of noble metal nanoparticles into the metal oxide nanostructures has been proposed to significantly improve their light-harvesting ability. This enhancement is primarily ascribed to the localized surface plasmon resonance (LSPR) effect associated with noble metal nanoparticles, which facilitates more effective utilization of light. Thus, in this study, we synthesized silver-doped nickel oxide (Ag:NiO) with varying Ag concentrations (0, 1, 2, 4, 6 wt%) to evaluate their photocatalytic performance. The X-ray diffraction (XRD) spectra revealed that NiO possesses a cubic crystalline structure, and a peak shift to a higher angle was noted for Ag doping, indicative of compressive strain. Further analyses of morphological, vibrational, and absorption properties were conducted through the acquisition of scanning electron microscopy (SEM) images, Raman spectra and UV–Vis absorption spectra, respectively. The photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) dyes was assessed, revealing that NiO with 4.wt.% Ag doping exhibited enhanced photocatalytic activity, achieving 99% degradation of MB and 90% degradation of RhB. Notably, Ag doping significantly enhances the light absorption capabilities and modifies the electronic structure of the NiO, thereby improving its performance in photocatalytic dye degradation. • A novel strategy is proposed to improve the photo-catalytic ability of wide bandgap NiO. • Different concentration of Ag was doped into the NiO lattice. • The LSPR properties of Ag dopants will significantly improve light absorption in the visible region. • Most importantly, 99 % of MB degradation and 90 % of RhB degradation were achieved by Ag dopants. • Catalyst's high degradation efficiency towards MB Dye can be highly useful in wastewater treatment. [ABSTRACT FROM AUTHOR]

• The present study exerted heavy metal (Lead) accumulation and translocation capability of Withania somnifera shoots under lethal and non-lethal doses of Lead • In planta synthesis of Lead nanoparticles indicates that the presence specialized detoxification, sequestration and reduction mechanism in in vitro shoot cultures of Withania somnifera • Adsorption and translocation of Lead to aerial parts (stems and leaves) of the cultures was facilitated by liquid culture medium, and the addition of plant growth regulator (BAP), chelating agent (EDTA) and other mineral ions (Mg2+, K2+, Ca2+ and others) in the growth medium • Shoots exposed to non-lethal doses of Pb (800 µM) over prolonged period (12 days), significantly increased biomass and secondary metabolite (withanolides) production. Green synthesis of nanoparticles using biological extracts/live organisms has been the best substitute for chemical/physical synthesizing methods. Live plants can convert simple metal ions into metal nanoparticles using their intrinsic metabolic processes. In addition, medicinal plants with a hyperaccumulation potential also have high reduction potential which can be utilized for in planta synthesis of metal nanoparticles. Lead (Pb), a non-essential heavy metal, is known to stimulate various biological processes in plants at higher concentrations. Therefore, a medicinal plant with a hyperaccumulation potential was selected to investigate its potential for in planta reduction of Pb. In the present study, in vitro grown 45 days old Withania somnifera (L.) Dunal shoots were exposed to lead acetate (PbAC 2) at varying concentrations (acute: 300–4800 µM; chronic: 50–800 µM) for 12–48 h and 4–12 days, respectively. It revealed that cultures grown in 800 µM PbAC 2 for 12 days of exposure (C5) recorded significantly higher biomass (17.28 g) and increase in the divalent metal ions such as calcium from 1412 (control) to 1787 mg kg-1 (C5), potassium 21,109 (control) to 24,779 mg kg-1 (C5), and iron from 11 (control) to 82 mg kg-1 (C5), with lead (Pb) accumulation reaching up to 405 mg kg-1 (C5). Compared to the control shoots (0.783, 0.805 & 1.3 mg g-1), C5 shoots positively correlated with secondary metabolites namely withaferin A (3.14 mg g-1) and withanolide A (0.960 mg g-1) production and negatively with withanone (1.027 mg g-1). Also, C5 shoots had spherical shaped nanoparticles with a mean particle size of 25±10 nm which was then identified as lead nanoparticles (PbNPs). To our knowledge, the present study is the first of its kind where the in planta synthesis of PbNPs/PbONPs by in vitro shoot cultures of W. somnifera is reported along with accumulation of higher biomass and selective withanolides under Pb stress. [ABSTRACT FROM AUTHOR]

Symmetric solid oxide cells (SSOCs) have attracted much attention due to their high energy conversion efficiency and simple manufacturing. The present study involves the synthesis of a class of double perovskite oxides, which serve as electrodes for SSOCs. These oxides exhibit exceptional stability in an oxidizing atmosphere, maintaining their single-phase double perovskite structure. Moreover, they facilitate the co-exsolution of metal nanoparticles from both A and B-sites under reducing conditions. By optimizing the doping amount of Bi in Sr 2- x Bi x FeTiO 6− δ (SB x FT), co-exsolved Bi and Fe nanoparticles decorated double perovskite oxides were obtained in reducing atmosphere and employed as high-performance electrodes for SSOCs. With Sr 1.2 Bi 0.8 FeTiO 6-δ as the electrode, the maximum power density achieves 537 mW cm−2 at 850 °C. In electrolysis mode, the current density for pure CO 2 electrolysis reaches 1.43 A cm−2 at an applied voltage of 1.5 V and 850 °C. All of these results indicate that co-exsolution of components on perovskite is an effective design technique for creating materials with desirable features. [Display omitted] • The novel co-exsolved metal nanoparticles decorated double perovskite oxides were obtained by Bi doping. • The Sr 2- x Bi x FeTiO 6 - δ were as the electrodes for symmetric solid oxide cells. • In SOFC mode, SB 0.8 FT exhibits excellent electrochemical performance. • In SOEC mode, SB 0.8 FT shows excellent CO 2 reduction properties and stability. [ABSTRACT FROM AUTHOR]

The catalytic reduction of methylene blue (MB) by metal nanoparticles and subsequent reoxidation is widely recognized and often referred to as a "redox reaction." The reduction mechanism of MB has been extensively studied and is well understood but its reoxidation has received little attention. Here we report an experimental study on the reoxidation dynamics of MB reduced by silver nanoparticles (Ag NPs). Ag NPs synthesized using the Pulsed Laser Ablation (PLAL) technique are used to reduce MB in the presence of the reducing agent NaBH 4. The reduction/reoxidation dynamics are monitored using UV−Vis spectroscopy through the decrease/increase of characteristic MB absorbance peak and color switching between methylene blue and leucomethylene (LMB). The influence of the various volumetric concentrations of Ag NPs and NaBH 4 on reoxidization dynamics of reduced MB is investigated. The reoxidation of reduced MB exhibited almost linear growth over time for different concentrations of both Ag NPs and NABH4 used in the reduction process. Higher NaBH 4 concentrations appeared to decelerate the reoxidation process, while the concentration of Ag NPs had no discernible impact on the reoxidation rate. The reduction of reoxidized MB after adding additional amounts of Ag NPs and NaBH 4 revealed that Ag NPs remained stable in the reaction medium but NaBH 4 deteriorated. Therefore, the deterioration of the NaBH 4 is identified as the major cause of the reoxidation of the reduced MB. A series of reduction-reoxidation experiments using chemically synthesized Ag NPs indicated that MB reoxidation is not limited to laser-synthesized Ag NPs. [ABSTRACT FROM AUTHOR]

Here in, a novel ternary manganese monoxide@nitrogen-doped carbon nanotube@cobalt composite was obtained via a scalable multistep reaction pathway. Mnganese monoxide (MnO) is adopted as the microwave transparent substrate to couple dielectric and magnetic components. The abundant internal voids of MnO and numerous interfaces between MnO and carbon can increase the dielectric loss to improve the microwave absorption (MA) performance, metal cobalt is employed as the magnetic component to enhance the magnetic loss. Benefiting from the synergistic effect of heterostructures, the ternary absorber exhibits the minimum reflection loss (RLmin) of −48.65 dB@8.1 GHz@2.8 mm and the effective absorption band (EAB) of 5.8 GHz with the thickness of 1.7 mm. Furthermore, the crystal structure, material components, surface element distribution and magnetic properties of the absorbers are characterized, the structure-performance correlation between "Physical properties" and "Electromagnetic performance" is established. Finally, the reliable MA mechanism based on "hierarchical component modulation" is summarized to guide the design of MnO-based absorbers. [ABSTRACT FROM AUTHOR]

In this study, we employed density functional theory (DFT) to investigate the adsorption sites and quantities of Li atoms on the C 48 B 12 surface. Additionally, we examined the hydrogen adsorption properties of the formed Li 12 C 48 B 12 through ab initio molecular dynamics (AIMD) simulations. Our AIMD simulations confirmed the stability of adsorbed Li atoms on the C 48 B 12 surface, computed adsorbed H 2 quantities, and predicted gravimetric densities of H 2 adsorption on Li 12 C 48 B 12 at 77 K and 298 K. Grand Canonical Monte Carlo simulations explored the H 2 gravimetric densities of pure MOF-5, C 48 B 12 -impregnated MOF-5, and Li 12 C 48 B 12 -impregnated MOF-5 at 77 K and 298 K within 100 bar. Li doping on the C 48 B 12 surface did not significantly enhance the gravimetric densities of H 2 in MOF-5 but enhanced the stability of H 2 adsorption in MOF-5. • 12 Li atoms stably interacted with C 48 B 12 and adsorbed 7.6 wt% H 2. • H 2 gravimetric densities for Li 12 C 48 B 12 were 4.3 wt% at 77 K and 3.0 wt% at 298 K. • Li doping on the C 48 B 12 enhances the stability of H 2 adsorption in Li 12 C 48 B 12 -MOF-5. [ABSTRACT FROM AUTHOR]

[Display omitted] Metal nanoparticles (MNPs) with complex structure and uniform distribution demonstrate interesting physicochemical properties and thus are widely applied. The traditional wet chemistry methods are commonly applied to construct MNPs structure, yet they still exhibit limitations in the liquid-phase environment, particularly, for synthesis of supported MNPs in one-step process. Diverse synthesis strategies have been investigated to design complex MNPs in a more efficient manner, among which the thermal treatment atmosphere induced solid-phase ion diffusion (TASID) synthesis strategy serves as an attractive strategy. This review summaries recent progresses of complex MNPs construction via TASID synthesis strategy, which realize the structure design through thermally treating the precursors under various gas atmosphere, such as oxidative, reductive, carbonaceous, and inert gas. This TASID strategy can both achieve the MNPs structure design and uniform dispersion simultaneously, demonstrating its unique properties. MNPs with diverse composition and structure, such as hollow, core@shell, yolk@shell, Janus, and multi-chamber structure, are successfully synthesized. The TASID synthesis mechanisms of galvanic replacement, Kirkendall effect, Ostwald ripening, carburization, and exsolution are elaborated in detail. The synthesis-mechanism-structure correlation of TASID is identified and the applications of these constructed MNPs are presented. This strategy could be developed into a class of synthetic methods by applying various thermal gas. [ABSTRACT FROM AUTHOR]

Silicate-based bioactive glass nano/microspheres hold significant promise for bone substitution by facilitating osteointegration through the release of biologically active ions and the formation of a biomimetic apatite layer. Cu-doping enhances properties such as pro-angiogenic and antibacterial behavior. While sol-gel methods usually yield homogeneous spherical particles for pure silica or binary glasses, synthesizing poorly aggregated Cu-doped ternary glass nano/microparticles without a secondary CuO crystalline phase remains challenging. This article introduces an alternative method for fabricating Cu-doped ternary microparticles using sol-gel chemistry combined with spray-drying. The resulting microspheres exhibit well-defined, poorly aggregated particles with spherical shapes and diameters of a few microns. Copper primarily integrates into the microspheres as Cu0 nanoparticles and as Cu2+ within the amorphous network. This doping affects silica network connectivity, as calcium and phosphorus are preferentially distributed in the glass network (respectively as network modifiers and formers) or involved in amorphous calcium phosphate nano-domains depending on the doping rate. These differences affect the interaction with simulated body fluid. Network depolymerization, ion release (SiO 4 4−, Ca2+, PO 4 3−, Cu2+), and apatite nanocrystal layer formation are impacted, as well as copper release. The latter is mainly provided by the copper involved in the silica network and not from metal nanoparticles, most of which remain in the microspheres after interaction. This understanding holds promising implications for potential therapeutic applications, offering possibilities for both short-term and long-term delivery of a tunable copper dose. A novel methodology, scalable to industrial levels, enables the synthesis of copper-doped ternary bioactive glass microparticles by combining spray-drying and sol-gel chemistry. It provides precise control over the copper percentage in microspheres. This study explores the influence of synthesis conditions on the copper environment, notably Cu0 and Cu2+ ratios, characterized by EPR spectroscopy, an aspect poorly described for copper-doped bioactive glass. Additionally, copper indirectly affects silica network connectivity and calcium/phosphorus distribution, as revealed by SSNMR. Multiscale characterization illustrates how these features impact acellular degradation in simulated body fluid, highlighting the therapeutic potential for customizable copper dosing to address short- and long-term needs. [Display omitted] [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]

Design and preparation of bifunctional electrocatalysts with optimized structures and abundant electrocatalytic active sites are significant for hydrogen generation in electrocatalytic water splitting. Herein, we have elaborately prepared Fe-doped CoP nanoparticles encapsulated in porous electrospun carbon nanofibers for bifunctional electrocatalysis on both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The morphologies, components, and properties of the prepared electrocatalysts are influenced by the introduction of a facile air calcination treatment. Porous nanostructure as well as the full conversion of metal active sites are simultaneously achieved. Owing to the protective electrospun carbon nanofibers as well as the abundant exposed active sites, the optimized electrocatalyst exhibits excellent pH-universal HER activities with small overpotentials (99 mV, 159 mV, and 185 mV) at 10 mA cm−2 in acidic, alkaline, and neutral electrolytes, and also presents remarkable OER performance. Moreover, a water electrolyzer cell, using the optimized electrocatalyst as the electrodes, manifests both a high efficiency (1.63 V@10 mA cm−2) and robust stability. This work provides a convenient route for the controllable fabrication of transition metal-based electrocatalysts toward energy conversion. [Display omitted] • Fe-doped CoP nanoparticles anchored in electrospun carbon nanofibers were prepared. • An effective, facile, and controllable air calcination strategy was introduced. • Porous structure and full conversion of metal sites were simultaneously achieved. • The optimized catalyst shows excellent activity and durability for water splitting. [ABSTRACT FROM AUTHOR]

Green synthesis of metal oxide nanoparticles is a cost-effective and sustainable approach that allows tailoring of the size and shape of the nanostructures for versatile applications. In this study, aloe vera extract-assisted sol-gel synthesis of nickel oxide nanoparticles (NiO x NPs) was explored for supercapacitor application. The NiO x NPs were synthesized at different aloe vera concentrations (2.5 and 5 wt%) and calcination temperatures (300, 400 and 500 °C). The phytochemical-assisted synthesis yielded NiO x nanopyramids with pores on their surface which widens as calcination temperature increases. As confirmed by XRD analysis, NiO x crystallite size also increased at higher calcination temperatures. Upon electrochemical characterization, NiO x -400B which was synthesized with 5 wt% aloe vera extract at 400 °C recorded the highest specific capacitance of 721 F g−1 at 1 A g-1 current density with the energy and power density of 10.38 Whkg−1 and 241.08 W kg-1 respectively. The charge storage mechanisms in the samples were gauged using Dunn's method which revealed that NiO x synthesized at higher calcination temperatures exhibited a greater contribution of the diffusion-controlled process. The optimized composition, NiO x -400B, also demonstrated excellent cycle stability by retaining up to 90.4 % of its original capacitance over 1500 cycles. This work is an attempt to investigate the viability of green synthesized nanoparticles in energy storage applications and the novel NiO x nanopyramid substantiates its prospect as a good electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

As a promising catalyst for electrochemical hydrogen evolution reaction (HER), WS 2 is currently focused due to its low cost and highly intrinsic activity. In this work, a 2H WS 2 film with metal W nanoparticles (W-WS 2) on the carbon cloth is constructed by the high-vacuum pulsed laser deposition under the in-situ heating condition. The uniform distribution of WS 2 provides abundant active sites, and a higher crystallinity with the incorporation of metal W nanoparticles on the W-WS 2 film effectively provides abundant electron on the S-edge. By combining the experiment and density functional theory calculations, it is found that the formation of a primary redox pair between metal W and S-edge on WS 2 makes the oxidation happen on the W nanoparticles, thus protecting the active S-edge sites. Finally, this typical W-WS 2 film shows an overpotential of 210 mV at the current density of 10 A cm−2 in 0.5 M H 2 SO 4 , which is superior to the commercial WS 2 powder (526 mV) or pure WS 2 film (341 mV). The W-WS 2 film from laser deposition exhibits the protective effect of W nanoparticles on WS 2 sites, which shows a lower HER overpotential of 210 mV at −10 mA cm−2 in acidic media. [Display omitted] • The micrometer-sized WS 2 pieces is restructured into nanofilm by laser deposition, exposing the S-edge sites. • The higher crystallinity of WS 2 and the incorporated metal W nanoparticles reduce the oxidation of WS 2. • The oxidation prefers to happen on metal W nanoparticles, which protects the active S-edge of WS 2. [ABSTRACT FROM AUTHOR]

• Eco-friendly synthesis of gold and silver nanoparticles using Solanum nigrum root extract, characterized using various techniques (XRD, UV–Vis, FTIR, TEM, SAED and EDAX). • Dose-dependent lung cancer activity is evaluated. • Environmental remediation against methylene blue and methylene orange dyes. • Antibacterial assessment targeting Salmonella typhi and Staphylococcus aureus. In this study, we utilized the natural reducing and stabilizing properties of Solanum nigrum root (SNR) to create nanoscale gold and silver particles, and explored their potential for anticancer, antibacterial, and photocatalytic applications. Natural source-based nanoparticle preparation was achieved by combining root extract with aqueous solutions of chloroauric acid and silver nitrate. The produced nanoparticles were recognized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible spectroscopy (UV–VIS), Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), and Energy-Dispersive X-ray spectroscopy (EDAX). Resulting nanoscale particles had diameters of 22.35 nm and 11.85 nm for gold and silver nanoparticles synthesized using a 5 ml SNR extract. While 16.06 nm and 8.72 nm sized gold and silver nanoparticles were synthesized using a 10 ml SNR extract. Their antibacterial properties were tested against Salmonella typhi and Staphylococcus aureus. Staphylococcus aureus showed the highest inhibitory activity. To evaluate the effectiveness of NPs in treating lung cancer, in vitro experiments were performed utilising the A549 cell line. The remarkable performance of gold and silver nanoparticles in the photocatalytic degradation of methylene blue and methylene orange was demonstrated. This research contributes to Solanum nigrum -derived metal nanoparticles and their multifunctional capabilities, paving the way for new prospects in cancer therapeutics, antibacterial agents, and environmental remediation strategies. [ABSTRACT FROM AUTHOR]

The low calorific value and poor atomization of biodiesel seriously hinder its application. The development of nanotechnology has led people to focus on using nanoparticles to improve the performance of biodiesel/diesel. Metal nanoparticles have a high surface volume ratio and good heat transfer properties, which can compensate for the poor performance of biodiesel. However, some conflicting results have been found in the literature. Therefore, this review aims to elucidate the effect of metal nanoparticle addition to biodiesel/diesel on engine performance and emission characteristics. The stability of the nanofluid is particularly important when applying metal nanoparticles. This paper provides a comprehensive overview of nanofluid preparation and stability enhancement strategies. Finally, the effects of nanoparticles on human health are also discussed. The results show that adding metal nanoparticles positively affects diesel engines' performance and emission characteristics. For stability studies, it was found that very few evaluations of the stabilization time of nanofluids have been conducted. In addition, further reduction of their effects on human health is needed before large-scale commercial use. All content has been carefully summarized with the aim of providing reference for future research directions. [Display omitted] • The preparation methods of metal nanoparticles and nanofluids are introduced. • Methods to improve the stability of nanofluids are summarized. • Observed that the use of metal nanoparticles can significantly improve engine performance and emissions. • The hazards of metal nanoparticles to human health are discussed. [ABSTRACT FROM AUTHOR]

Cancer, a complex and heterogeneous disease, arises from genomic instability. Currently, DNA damage-based cancer treatments, including radiotherapy and chemotherapy, are employed in clinical practice. However, the efficacy and safety of these therapies are constrained by various factors, limiting their ability to meet current clinical demands. Metal nanoparticles present promising avenues for enhancing each critical aspect of DNA damage-based cancer therapy. Their customizable physicochemical properties enable the development of targeted and personalized treatment platforms. In this review, we delve into the design principles and optimization strategies of metal nanoparticles. We shed light on the limitations of DNA damage-based therapy while highlighting the diverse strategies made possible by metal nanoparticles. These encompass targeted drug delivery, inhibition of DNA repair mechanisms, induction of cell death, and the cascading immune response. Moreover, we explore the pivotal role of physicochemical factors such as nanoparticle size, stimuli-responsiveness, and surface modification in shaping metal nanoparticle platforms. Finally, we present insights into the challenges and future directions of metal nanoparticles in advancing DNA damage-based cancer therapy, paving the way for novel treatment paradigms. Metal nanoparticles offer a versatile programmable platform for precise DNA damage induction and synergistic various tumor treatment strategies to effectively treat tumors. [Display omitted] [ABSTRACT FROM AUTHOR]

Pt-based alloy catalysts are popular for fuel cell oxygen reduction reactions (ORRs) because of their high activity and low cost. However, during the preparation and reaction processes, metal nanoparticles tend to aggregate, which affects the activity and stability of the catalyst. To address this issue, this work uses Zeolite-type imidazolic acid framework material (ZIF) crystal shells to coat PtCu alloy catalysts, and N-doped nanoporous carbon layers derived from ZIFs are used to protect individual metal nanoparticles. The appropriate thickness of the ZIF-derived carbon protective layer is reported to effectively inhibit the aggregation of metal nanoparticles during high-temperature calcination, improve the utilization rate of Pt atoms and enhance the activity and stability of Pt-based catalyst. N-doping stabilizes the metal nanoparticles by enhancing their interaction with carriers. Electrochemical test results demonstrated that the mass activity of the prepared 3-Co-PtCu/NC is 6.9 times and 4.3 times that of commercial Pt/C and PtCu/C, respectively. Furthermore, the excellent half-wave potential is maintained even after 10,000 cycles. In single-cell test, the performance of 3-Co-PtCu/NC is better than Pt/C. This study provides a strategy for controlling the aggregation and detachment of metal nanoparticles in metal-based catalysts, which is conducive to improving the performance of catalysts. [Display omitted] • PtCu alloy particles are coated in ZIF-derived nanoporous N-doped C layers. • N-doped C layer derived from ZIF can effectively inhibit the aggregation and dissociation of metal particles. • 3-Co-PtCu/NC show improved activity for ORR by integrating multiple advantages. • 3-Co-PtCu/NC exhibited excellent performance in fuel cell. [ABSTRACT FROM AUTHOR]

This study demonstrates the significant effect of incorporating inexpensive transition metal nanoparticles into metal-organic frameworks (MOFs) to improve their room-temperature hydrogen storage properties. Low-cost nanoparticles (Cu, Ni, and CuNi) were incorporated into UiO-66(Zr) via the double-solvent approach (DSA) plus chemical reduction processes. All composites exhibited higher hydrogen storage capacity compared to pure UiO-66 at both room temperature and 60 bar. Notably, the hydrogen spillover efficiency of CuNi nanoparticles loaded in UiO-66 was comparable to that of MOF adsorbents embedded with noble metals such as Pd and Pt. The hydrogen storage capacity of CuNi@UiO-66 was significantly increased from 0.20 wt% to 0.74 wt%. DFT calculations showed that the CuNi alloys facilitated the adsorption and dissociation of hydrogen molecules in comparison to the single metal nanoparticles, thus favoring the hydrogen spillover effect and improving the hydrogen storage performance. This work demonstrates the potential of designing MOF loaded with inexpensive metal nanoparticles for optimized room-temperature hydrogen storage. [Display omitted] • The inexpensive Cu, Ni, and CuNi NPs were doped into UiO-66 using the dual-solvent approach plus chemical reduction method. • The room-temperature hydrogen storage capacity of UiO-66 was improved by incorporating Cu, Ni, and CuNi NPs into UiO-66. • CuNi@UiO-66 showed comparable improvement in room temperature hydrogen storage compared to other MOFs doped with noble metals. • The CuNi alloy enhances H 2 adsorption and dissociation, improving hydrogen storage through spillover effect. [ABSTRACT FROM AUTHOR]

A hybrid aerogel structure for hydrogen sensing was produced and tested, which consists of Pd nanoparticles decorated on a TiO 2 aerogel skeleton structure with large specific surface areas and high porosity. The effects of decorated with different contents of Pd nanoparticles on the microstructure of anatase TiO 2 aerogel and the hydrogen response characteristics were investigated. The contribution of the doping of Pd nanoparticles to the specific selectivity of the anatase phase TiO 2 aerogel for hydrogen sensing was investigated. Benefiting from highly interconnected porous networks of aerogel, ultra-large specific surface area, and homogeneous Pd nanoparticles dispersion, the resulting Pd nanoparticle-decorated TiO 2 3D hybrid aerogel hydrogen sensors express high hydrogen sensing performance. The response was 4.8 toward 100 ppm hydrogen at the optimal working temperature of 325 °C, with a short response time (<2 s), short recovery time (<22 s), and high selectivity and long-term stability. A hydrogen-sensitive mechanism is proposed in which metal atom doping causes more oxygen defects in metal oxide semiconductor lattice. The approach of constructing aerogel network structures by decorating metal nanoparticles on metal oxide semiconductors provides a new way to develop gas sensors. • Pd nanoparticles-decorated TiO 2 aerogel structure was prepared by sol-gel method and supercritical drying method for hydrogen sensing. • Very large specific surface areas and highly interconnected porous networks. • Short response time(<2s) and recovery time(<22s) of anatase Pd-modified TiO 2 aerogel structure for hydrogen sensing. • High selectivity of Pd nanoparticles-decorated anatase phase TiO 2 aerogel structure for hydrogen sensing. [ABSTRACT FROM AUTHOR]

Nanotechnology has been developing tremendously since the 1970s. Various types of nanoparticles such as carbon, metal, bio-originated, etc. have been synthesized by a variety of physical, chemical and biological methods. Biological methods which employ bacteria, fungi and plants for the synthesis of metal nanoparticles are found to be a sustainable and eco-friendly approach. Among biological methods, plants being a cleaner and greener source are widely accepted. The present work includes screening the synthesis of silver nanoparticles using the roots and leaves extract of 15 different Indian Crinum species, optimization, characterization and kinetic studies of silver nanoparticles. Among all the species, the highest synthesis was observed by Crinum moorei which was detected by apeak at 390 nm in UV–visible spectrophotometry. The optimization of silver nanoparticle synthesis from C. moorei roots was performed based on extract concentration (1 %), salt concentration (1.5 mM), pH (9) and temperature (30°C). The kinetics study of silver nanoparticles showed a rate constant of 0.0609 h−1. Furthermore, the characterization of synthesized silver nanoparticles was conducted using TEM, SEM, FTIR, XRD, NTA and DLS. These synthesized AgNPs exhibited catalytic activity for Congo red dye decolorization, which could serve as an initiative for the further studies to control the environmental pollution caused by dyes and colorants. [Display omitted] • First report of synthesis of AgNPs using root extracts of Crinum moorei. • Characterization of synthesized AgNPs using UV-visible spectroscopy, FESEM, TEM, NTA, XRD and FTIR. • Kinetics of synthesis of AgNPs. • Catalytic activity of AgNPs in degradation of Congo red. [ABSTRACT FROM AUTHOR]

As tribo-catalysis gains increasing attention to harness mechanical energy for environmental remediation, it is time to explore its application to those organic pollutants that have been challenging to degrade. In this study, four commercial metal oxide nanoparticles, BaTiO 3 , ZnO, P25 TiO 2 , and DXN-RT30 TiO 2 nanoparticles, were stimulated through magnetic stirring to degrade 20 mg/L methyl orange (MO) and 30 mg/L methylene blue (MB) solutions. While all the other nanoparticles showed rather poor performance, DXN-RT30 TiO 2 nanoparticles performed exceptionally well: With Teflon magnetic disks rotating at 400 rpm, 98.2% of MO and 100% of MB were degraded within 330 and 420 min, respectively. DXN-RT30 TiO 2 nanoparticles demonstrated a unique absorption for MB molecules, yielding significantly different outcomes in active species trapping experiments between degradation of MO and MB solutions by DXN-RT30 TiO 2. Complemented by electron paramagnetic resonance analysis, our findings suggest that for DXN-RT30 TiO 2 nanoparticles under magnetic stirring, MO molecules are degraded by h+, ·OH, and e− in solution, while MB molecules are absorbed and degraded via h+ and e− on the surface of DXN-RT30 TiO 2 nanoparticles. This study identifies DXN-RT30 TiO 2 nanoparticles as a cost-effective, high-performance, and environmentally friendly tribo-catalyst for environmental remediation, stimulating further exploration for more excellent tribo-catalysts. [ABSTRACT FROM AUTHOR]

Aqueous phase selective hydrogenation of cinnamaldehyde (CALD), as a representative α,β-unsaturated aldehyde, into cinnamyl alcohol (CALA) has been investigated over monometallic Ru and bimetallic RuCo catalysts on pristine h-BN support. Using water as the solvent, the optimal 0.5%Ru-1.1%Co/h-BN catalyst exhibits 510 h−1 specific reaction rate and 78.9 % CALA selectivity as well as good recycling stability at 100 °C. Based on the structure characterizations of catalysts, metal nanoparticles consisting of metallic Ru0 and partially oxidized Ruδ+ sites are uniformly dispersed on h-BN thin sheets. In comparison to monometallic catalysts, additive Co metals in bimetallic RuCo/h-BN catalysts play significant geometric and electronic modification roles on Ru active sites depending on the Ru/Co ratio, and therefore remarkably enhances the preferential activation of CALD C O bond and selectivity of CALA product as well as accelerates the catalytic reaction. Furthermore, the hydrogen dissociative activation ability of various Ru and RuCo catalysts was evaluated, while the superior catalytic performance in water than other commonly used solvents was also clarified and discussed. [Display omitted] • h-BN-supported bimetallic RuCo catalyst exhibits high activity and selectivity in cinnamaldehyde C O hydrogenation. • Co additive metal plays geometric and electronic modification roles on Ru active site. • Partially oxidized Ruδ+ and decorated CoO x serve as Lewis acid sites for enhancing C O activation. • Hydrogen dissociative activation ability can be promoted by bimetallic RuCo catalyst. • Water as the solvent plays multiple positive roles of polarizing C O bond and hydrogen transfer. [ABSTRACT FROM AUTHOR]

Electrolytic paste (EP) from used batteries was innovatively utilized as a support for Ni–Co nanoparticles (Ni–Co NPs) to catalyze hydrogen evolution from NaBH 4. The materials exhibited a porous and heterogeneous morphology, characterized by a ZnMn 2 O 4 interplanar distance of 0.34 nm, as confirmed by SAED analysis. Elemental analysis identified carbon, nitrogen, hydrogen, and sulfur, while ICP-MS quantified zinc, manganese, and iron. XRD unveiled an amorphous broad peak at 2θ = 13.3–39.8°, with additional phases identified as ZnO, graphite, simonkolleite, manganese oxides, and hetaerolite. Raman spectroscopy showcased characteristic bands typical of carbonaceous materials. FTIR detected functional groups alongside Ni–O, Co–O, and Zn–O bonds. Various Ni/Co ratios were assessed, and the 25:75 and 20:80 (w/w) ratios showed optimal performance, yielding hydrogen at rates of 238.1 and 278.0 mL H 2 g catalyst −1 min−1, respectively. The determined activation energy was 32.76 kJ mol−1. The turnover frequency reached 1823.93 mL H 2 g catalyst −1 min−1 (328.15 K), and the catalyst exhibited satisfactory performance over 16 reuse cycles. [Display omitted] • Recovery of electrolytic paste (EP) from spent Zn–C batteries. • EP decorated with bimetallic Ni–Co (8:2) nanoparticles (NPs). • Hydrogen evolution from NaBH 4 catalyzed by Ni–Co NPs (8:2)/EP. • Ni–Co NPs (8:2)/EP can be reused up to 16 cycles. • The maximum turnover frequency was 1617.34H 2 g catal −1 min−1 (55 °C). [ABSTRACT FROM AUTHOR]

Synthesis of a composite with high technical performance and low cost instead of Platinum-based electrocatalysts has become an investigation hotspot to develop fuel cells and storage technologies. So, in the current investigation, three new bifunctional electrocatalysts incorporating lanthanides into Zeolitic Imidazolate Framework (ZIF)-8 are fabricated and assessed. First, by using a facile protocol, three trimetallic composites consisting of Europium (Eu), Samarium (Sm), Copper (Cu), and ZIF-8 are prepared, and the fabricated samples are labeled as EuCu-ZIF, SmCu-ZIF, and SmEuCu-ZIF. Next, in order to eliminate the irreversible fusion and quick aggregation of metal nanoparticles through the high-temperature carbonization process, the mesoporous-silica-protected calcination technique is investigated. After the Hydrofluoric (HF) etching process, the Cu@Ln (Eu, Sm)-N-C electrocatalysts are formed. Based on the fabricated samples, the Cu@Eu-N-C electrocatalyst exhibited the best Oxygen Reduction Reaction (ORR) performance with an onset potential of −0.06 V vs Ag/AgCl. Additionally, the electron transfer number for this composite is found to be 3.68. The GCD experiments show that the Cu@Eu-N-C electrode has the greatest specific capacitance, measuring 431 F g−1 when tested at 1 A g−1. It is deduced that the introduction of Eu3+ and Sm3+ as metal ions in the ZIF-8 catalyst led to an improvement in defects in the carbon matrix and mass transfer, illustrating the fabricated catalysts have an acceptable efficiency for ORR and storage applications. Indeed, due to the use of metallic ions (Ln and Cu), highly effective active sites were formed, resulting in an outstanding improvement in ORR efficiency. Also, it was found that with the use of mesoporous-silica protection for the fabricated samples, there is a remarkable improvement in the onset potential and specific capacitance parameters. [Display omitted] • Incorporation of the lanthanides (Sm, Eu) and ZIF-8 has acceptable performance for ORR and supercapacitor. • In this investigation, three novel trimetallic electrocatalysts are synthesized and analyzed. • The impact of using the mSiO 2 coating technique on electrochemical aspects is investigated. • Based on the LSV curves, the onset potential of Cu@Eu-N-C was obtained as −0.06 V vs. Ag/AgCl. • The GCD measurements indicated that the specific capacitance of Cu@Eu-N-C at 1 A g−1 was 431 F g−1. [ABSTRACT FROM AUTHOR]

To degrade the tryptophan molecule through photocatalysis, the exploitation of solar energy in the present study necessitated the use of visible light active photocatalysts. Iron-transition metal nanoparticles were deposited on the surface of TiO 2 powders through an impregnation method to obtain X%Fe-TiO 2 for the purpose of improving the optical absorption of TiO 2 in the visible light region. The effects of iron percentage (X%: 2,4 and 5), iron oxidation state and pH on the photocatalytic performance of TiO 2 modified under solar irradiation were thoroughly studied. The characterization results by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS) and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM-EDS) indicate that iron nanoparticles were successfully fixed on the TiO 2 surface. The absorption wavelengths of all X%Fe-TiO 2 photocatalysts shifted towards the visible, confirming successful modification of the TiO 2 surface with iron. Based on the empirical results, X%Fe-TiO 2 nanomaterials demonstrate a higher activity compared with the unmodified TiO 2 under solar irradiation. The 4%Fe(III)-TiO 2 photocatalyst, in particular, displayed the highest photocatalytic activity at natural pH. The degradation was complete in 60 min. Therefore, it is interesting to note that iron had more functions and benefits than noble metals. The mechanism of the Fe-TiO 2 system has been proposed in detail. [Display omitted] • The TiO 2 surface has been successfully modified through a simple impregnation process. • 4% Fe(III)-TiO 2 is the most efficient photocatalyst under solar irradiation. • Iron has more functionalities and advantages than noble metals. • Fe3+ ions reduce the recombination of (e−/h+) pairs, thus enhancing the photocatalytic activity. • Photocatalytic efficiency of Fe-TiO 2 depends on the percentage, degree of iron oxidation and pH. [ABSTRACT FROM AUTHOR]

The specific behaviour of kaolinites heated between 600 and 800 °C (metakaolinite) makes this material very appropriate to be used as: i) ecological pozzolanic additive to ordinary Portland cement (OPC), ii) precursor of geopolymers, iii) carrier/supplier of metal nanoparticles with bactericidal/virucidal activity, and iv) catalytic reactions. The strong reactivity of the metakaolinite (mixed 2SiO 2.Al 2 O 3 oxide) is mainly associated with the presence of a large fraction (>50 %) of five-coordinated aluminum in its disordered structure. The thermal treatment of the metakaolinite favours the formation of the stable mullite below 1250 °C. The alkaline activation of metakaolinite produces geopolymers with remarkable mechanical properties, which reduce the CO 2 emission associated to the OPC cement manufacture. This metakaolinite-derived geopolymers also permit the homogeneous and safe stockage of contaminants radioactive Cs and Sr cations. Finally, the retention of Ag and Cu nanoparticles at the metakaolin surface has been successfully used as support as well as dispenser of antimicrobial/virucidal agents. This fact opens the possibility to use metakaolinite as support for another kind of metal nanoparticle (i.e. Pt, Rd, Au, Pd, etc) in catalytic applications as well as in health. This critical review provides an overview of the importance of the metakaolin structure in its main applications. [ABSTRACT FROM AUTHOR]

Recently, ruthenium telluride (RuTe 2) has received widespread attention as an effective HER catalyst. In this work, ultrafine and well-dispersed RuTe 2 nanoparticles anchored on nitrogen and boron co-doped graphene (RuTe 2 /BNG) was developed by freeze-drying and facile pyrolysis method, demonstrating a brilliant HER performance. The overpotential of RuTe 2 /BNG at the current density of 10 mA cm−2 is only 34 and 16 mV in 0.5 M H 2 SO 4 and 1.0 M KOH solution, respectively. More importantly, the RuTe 2 /BNG can also maintain significantly robust HER stability during long-term chronopotentiometry measurements. The outstanding HER activity of RuTe 2 /BNG should be ascribed to its properties with abundant defects, large specific surface area, high electronic conductivity and short mass transfer path. Our work offers a new path to fabricate efficient HER catalysts by homogeneously anchoring RuTe 2 on B, N co-doped graphene. [Display omitted] • Ultrafine RuTe 2 nanoparticles anchored on B, N co-doped graphene (RuTe 2 /BNG) was developed by facile pyrolysis method. • The TEM result manifests that the average diameter of RuTe 2 nanoparticles in RuTe 2 /BNG is about 2.6 nm. • The RuTe 2 /BNG catalyst exhibits an outstanding HER activity and stability in both acid and alkaline media. • The influences of the B or N doping on the structure, chemical state and HER activity of catalysts were investigated. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations were conducted to investigate the coalescence mechanism of carbon nanoparticles. The analytical objects were two clusters composed of benzene, anthracene, phenanthrene or coronene molecules, and those clusters were placed next to each other. These numerical analyses used isoPAHAP potential to describe the intermolecular interaction and OPLS–AA potential to account for intramolecular interaction. Since the behavior below and above the melting point is entirely different, the melting point of the cluster was first determined. The coalescence behavior was investigated at temperatures 30 K below the melting point, 5 K below the melting point, and 50 K above the melting point. The coalescence of benzene clusters progressed through three stages: fast shrinking at 0–0.4 ns; gradual and constant shrinking at 0.4–4 ns; and little shrinking after 4 ns. This indicates that the coalescence of benzene clusters is analogous to that of inorganic nanoparticles. However, the number of coalescence stages of coronene clusters was more than four. The coronene cluster looked composed of 4–6 molecules of crystallites. Due to the strong interaction among molecules within crystallites, the diffusion of molecules in crystallites would hardly occur. Thus, the coalescence of coronene clusters would proceed with the breaking of crystallites. [Display omitted] • Carbon nanoparticles were assumed as PAH clusters. • Coalescence of carbon nanoparticle was investigated by MD simulation. • Coalescence was multi-staged, different mechanism from metal nanoparticles. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is an essential element for maintaining normal metabolism in vertebrates. Mn dioxide nanoparticles (MnO 2 NPs), a novel Mn source, have shown great potentials in biological and biomedical applications due to their distinct physical and chemical properties. However, little is known about potential adverse effects on animal or cellular metabolism. Here, we investigated whether and how dietary MnO 2 NPs affect hepatic lipid metabolism in vertebrates. We found that, excessive MnO 2 NPs intake increased hepatic and mitochondrial Mn content, promoted hepatic lipotoxic disease and lipogenesis, and inhibited hepatic lipolysis and fatty acid β-oxidation. Moreover, excessive MnO 2 NPs intake induced hepatic mitochondrial oxidative stress, damaged mitochondrial function, disrupted mitochondrial dynamics and activated mitophagy. Importantly, we uncovered that mtROS-activated phosphorylation of heat shock factor 1 (Hsf1) at Ser326 residue mediated MnO 2 NPs-induced hepatic lipotoxic disease and mitophagy. Mechanistically, MnO 2 NPs-induced lipotoxicity and mitophagy were via mtROS-induced phosphorylation and nucleus translocation of Hsf1 and its DNA binding capacity to plin2 / dgat1 and bnip3 promoters, respectively. Overall, our findings uncover novel mechanisms by which mtROS-mediated mitochondrial dysfunction and phosphorylation of Hsf1S326 contribute to MnO 2 NPs-induced hepatic lipotoxicity and mitophagy, which provide new insights into the effects of metal oxides nanoparticles on hepatotoxicity in vertebrates. [Display omitted] • MnO 2 NPs increased Mn and lipid contents, promoted lipogenesis, and inhibited lipolysis and fatty acid β-oxidation. • MnO 2 NPs induced mitochondrial oxidative stress, damaged mitochondrial structure and function, and activated mitophagy. • mtROS-activated phosphorylation of Hsf1Ser326 residue mediated MnO 2 NPs-induced hepatic lipotoxicity and mitophagy. • MnO 2 NPs-induced lipotoxicity and mitophagy were via mtROS-induced Hsf1 phosphorylation and bnip3 activation. • Hsf1 mediated MnO 2 NPs-induced lipotoxicity through transcriptional activation of plin2 and dgat1. [ABSTRACT FROM AUTHOR]

Hydrothermal gasification is a promising technology for converting biomass into syngas (H 2 /CO). A substantial challenge of hydrothermal gasification for producing hydrogen is the unwanted deposition of graphitic coke and metal particle agglomeration on the catalyst active sites. In this contribution, we hypothesize and examine controlling the active site nickel nanoparticle size (2, 9, 23 and 32 nm) through synthesis on supported mesoporous alumina (Al 2 O 3). Nanoparticles were synthesized from nickel acetylacetonate (Ni(acac) 2) by varying the molar ratio of oleylamine (OA) to trioctylphosphine (TOP) which gave controlled sizes of nanoparticles. Based on catalyst analysis, the 11 wt% Ni–Al 2 O 3 containing 2 nm Ni was further evaluated for hydrothermal gasification of glucose for the production of syngas (H 2 /CO) at 500 °C temperature and 30 min reaction time. This nanocatalyst was found to significantly increase H 2 yield compared to a previously prepared impregnated catalyst having larger Ni active sites. Graphitic coke deposition was minimized while the total organic carbon destruction (TOC) and carbon gasification efficiency (CGE) were both enhanced with the nanocatalyst. Almost double the yield of H 2 (1.94 times higher) was achieved compared to the impregnated catalyst. This is attributed to the larger surface area, higher percentage of metal dispersion and uniform size distribution of active metal nanoparticles on the support. [Display omitted] • Catalytic activity is enhanced by reducing the active metal particle size. • Colloidal synthesis of Ni nanoparticles significantly prevents agglomeration and enhances higher metal dispersion. • Ni nanoparticles decorated mesoporous Al 2 O 3 is an efficient catalyst for H 2 production from glucose. [ABSTRACT FROM AUTHOR]

Transition metal nanoparticles supported on porous carbon materials as hydrothermal stable and highly effective catalysts are increasingly attracting worldwide attention. Herein, a controllable electrospinning technique was employed to prepare the promising catalysts to produce hydrogen. Different proportions of polymethyl methacrylate and nickel nitrate were introduced into polyacrylonitrile spinning solution to prepare nanoscale Ni encapsulated in porous carbon nanofiber (Ni@PCNF) through an in-situ pore-making strategy. The results show that the prepared 10 wt% Ni@PCNF catalyst possesses an enhanced specific surface area, hierarchical porous structure, and uniformly-dispersed Ni nanoparticles (∼17 nm). This porous and fibrous catalyst presents relatively high performance of producing high-purity H 2 by aqueous phase reforming of glycerol compared with several reference catalysts on different supports (e.g., activated carbon fibers and γ-Al 2 O 3) under similar reaction conditions. The selectivity and purity of H 2 produced by 10 wt% Ni@PCNF catalyst at 260 °C for 1 h are nearly 100% and 93%, respectively. This is related to the moderate catalytic activity of active Ni nanoparticles encapsulated in PCNFs. By contrast, those Ni nanoparticles supported on the reference supports show a high catalytic activity and thus produce low-purity H 2 due to the considerable byproducts of CH 4 , CO and CO 2. Moreover, Ni@PCNF catalyst exhibits a good structure stability and reuse effect in comparison with reference catalysts. This work provides a roadmap for preparing effective and stable Ni-based catalysts to produce high-purity H 2 from cheap glycerol through a low-temperature thermocatalysis. [Display omitted] • Porous and fibrous Ni@PCNF catalyst was facilely fabricated by electrospinning technique. • 10 wt% Ni@PCNF catalyst produced high-purity H 2 (93%) from glycerol solution. • The catalytic activity of Ni-based catalysts dominated the yield and purity of H 2 produced. • Ni@PCNF catalyst exhibited a robust stability in structure and reuse effect after the hydrothermal reaction. [ABSTRACT FROM AUTHOR]

Combustible dust may result in a catastrophic dust explosion with much larger accident consequences than gas explosions. In this study, porous materials are explored as a promising solution for mitigating explosions. This study focussed on the investigation of aluminium powder explosion in the influence of ceramic foam, with and without coating with non-precious nickel nanopowders. The microscopic properties and structural characteristics of the ceramic foam were analyzed using X-ray spectroscopy, X-ray diffractometry, and scanning electron microscopy. The findings revealed that the nickel-coated ceramic foams are non-uniform and almost spherical in shape, with obvious agglomerations of metallic-silica present on the strut structure. Compared to non-coated ceramic, it can be said that nickel-coated ceramic foams demonstrate a significant reduction in maximum overpressure by approximately 10%. This suggests that the interconnected micro-network structure of the nickel-ceramic walls aids in quenching the flame of the aluminium dust explosion and hence, suppressing the overpressure. [ABSTRACT FROM AUTHOR]

The design and development of silver and gold nanoparticles incorporated into silk fibroin and gelatin composite nanofibers were prepared using the electrospun method. The functional group, chemical composition, and thermal stability of composite nanofibrous scaffolds were investigated using different characterization techniques. The confirmation of SF/GL/Ag-Au composite nanofibers was achieved through FE-SEM and AFM images, which proved to be highly beneficial for assessing surface morphology, thickness, and roughness area (Ra) with dimensions of 777 nm and 292.71 nm, respectively. Furthermore, HR-TEM images were used to elucidate the morphological structure and size of metal nanoparticles in SF/GL/Ag-Au composite nanofibers, revealing an average diameter length of 220.85 ± 82.65 nm for Ag and Au nanoparticles sizes noted at 6.25 nm and 11.56 nm. In addition, flow cytometry analysis of SF/GL/Ag-Au composite nanofibers was conducted to assess the viability of L929 cells and detect the apoptosis levels. Furthermore, invivo wound healing studies were performed on Sprague-Dawley rat animals. The results demonstrated that SF/GL/Ag-Au composite nanofiber scaffolds significantly accelerated wound closure, achieving a remarkable 99.58 % wound healing rate in the 21 days compared to control groups. In conclusion, our findings highlight that SF/GL/Ag-Au composite nanofiber scaffolds are highly suitable for wound dressing applications. [Display omitted] • The SF/GL/Ag-Au composite nanofiber was prepared through the electrospinning method. • Silk fibroin and gelatin act as reducing and stabilizing agents for metal nanoparticles. • The average diameter length of SF/GL/Ag-Au composite nanofibers is 220.85 ± 82.65 nm. • Flow cytometry analysis is more beneficial for detecting apoptosis and cell viability. • SF/GL/Ag-Au composite nanofiber is the most effective material for wound dressing applications. [ABSTRACT FROM AUTHOR]

The metal nanoparticles (MNPs) are tremendously being used as growth-promoting agents in agricultural crops. One such MNP is iron nanoparticle (FeNP) as iron is an essential growth element for plants. In the current study, a unique method is employed to recycle kitchen waste (KW) and employ it in the synthesis of FeNPs. Further, the growth-promoting activity of these particles was assessed on Vigna radiata (Mung bean). The FeNPs were prepared using KW extract containing crucial phytocompounds as identified using GC-MS analysis. The synthesized KW-FeNPs were ellipsoidal/spherical in shape (150–185 nm) and had -6.14 mV Z-potential. Nano-priming of the seeds at varying concentrations of FeNPs (50–150 ppm) was done before germination of the seeds along with spraying of FeNPs throughout the growth period of the plantlets. In vitro and in vivo growth parameters were evaluated after the 10th and 21st day respectively. The seedlings sprayed with 150 ppm KW-FeNPs showed a highly significant increase in SL (21.63 ± 2.66 cm), RL (7.21 ± 2.11), and seedling length (28.85 ± 2.41) when compared to the control. The lower values of the S/R ratio (3.40–4.49) and increased number of lateral roots were seen in seedlings treated with Kw-FeNPs. A significant (13.02 ± 0.12 mg/g of leaves) and highly significant (17.01 ± 0.82 mg/g of leaves) increase in chlorophyll content was observed in 100 and 150 ppm KW-FeNPs treated plantlets respectively. The synthesized NPs were able to stimulate seedling and plantlet growth even at lower concentrations. A dose-dependent increase in all the plant growth parameters was observed till 150 ppm KW-FeNPs treatment without any visible sign of oxidative stress. The present research work has successfully utilized kitchen waste in the synthesis of a metal-based nanofertilizer for sustainable agricultural practice. [Display omitted] • The study highlights recycling of kitchen waste in production of iron nanoparticles. • Enhanced growth of Vigna radiata was observed in the presence of KW-FeNPs. • KW-FeNPs treatment showed a significant increase in G%, SL, RL, seedling length and lateral roots of Vigna radiata. • Increased chlorophyll content indicated improved photosynthetic rates after KW-FeNPs treatment. • No doses of KW-FeNPs show oxidative stress in plantlets. [ABSTRACT FROM AUTHOR]

Significant optical nonlinearities in amorphous nanocomposites are essential for developing advanced communications and photonic devices. In this regard, the borate glasses are considered substantial and readily available commercial hosts. The present work demonstrates the white light emission and decay properties in lithium bismuth boro-phosphate glasses reinforced with gold nanoparticles (AuNPs) prepared via melting and quenching technique. Also, their non-linear optical properties are evaluated in the present study. Numerous characterization methods were used to extensively examine the produced glasses, including XRD, HR-TEM, FTIR, XPS, MAS-NMR, DSC, UV–Visible, Photoluminescence, and Z-scan techniques. Following the addition of AuNPs into the glass matrix, an increase in the refractive index and density of the glasses was observed. The amorphous features of the glass sample are disclosed by XRD examination, and DSC research demonstrates the thermal stability of the glasses after the addition of AuNPs, as shown by the rise in T g values from 459 °C to 486 °C. HR-TEM results reveal the presence of Au metal nanoparticles having a cubic crystal structure with an average size of 14 nm, while XPS analysis shows that the valence of Au is 0, i.e. Au0 or, in other words, the metallic nature of gold in glasses. FTIR, MAS-NMR, and UV–Visible spectral studies demonstrate the substantial modifications in the physical, structural, and optical properties brought about by incorporating AuNPs into the glass matrix. The PL spectra of glasses containing AuNPs show three distinct, sharp emissions at 494, 611, and 738 nm, out of which the blue emission (494 nm) is found to be predominant and has an overall emission in the region of yellow on the CIE diagram with an average lifetime of 12.23 μs. Glasses containing AuNPs have a white light correlated colour temperature (CCT) of 5129 K and CIE chromaticity (x, y) coordinates of (0.346, 0.413). Additionally, we utilized a Z-scan technique to measure the nonlinear absorption coefficient and nonlinear refractive index. Our experimental data show that the values obtained are consistent with the theoretical closed and open aperture values. Based on our findings, it appears that the glasses we prepared have the potential to be utilized in optical switching applications. [ABSTRACT FROM AUTHOR]

Surface-Enhanced Raman Spectroscopy (SERS) is a powerful analytical technique for detecting trace analytes using noble metal nanoparticles. In this paper, we present a novel approach to construct a high-performance SERS sensing platform using self-assembled gold nanoparticles on aminated glass capillaries. The surface self-assembly technology ensures uniformity and repeatability of the SERS substrate, addressing the challenges of poor reproducibility observed in conventional methods. The 30 nm gold nanoparticles exhibit excellent plasmonic properties and biocompatibility, making them ideal candidates for SERS applications. We conducted SERS detection using Rhodamine 6G (R6G) as probe molecules, achieving a minimum detectable concentration of 0.1 nM for the AuNPs/GS substrate and 0.1 pM for the S-AuNPs/GC substrate. The S-AuNPs/GC substrate demonstrated commendable uniformity and repeatability, with a relative standard deviation of 12.1 %. Machine learning techniques, including baseline correction, normalization, and smoothing, were employed for data processing, enhancing the accuracy and reliability of the SERS analysis. By employing the K-means clustering algorithm, we identified three distinct groups of spectral characteristics. Additionally, Principal Component Analysis (PCA) allowed visualization and understanding of the clustering results in a two-dimensional space, capturing approximately 86.74 % of the data's variance. The successful construction of a high-performance SERS sensing platform with enhanced sensitivity, accuracy, and reliability, assisted by machine learning, holds great potential for various applications in chemical sensing, environmental monitoring, and biomedical diagnostics. [ABSTRACT FROM AUTHOR]

The coalescence behavior of soot and carbon black has not been so much discussed. The coalescence rate was obtained from the previous experimental results which measured the decrease in mobility diameter by re-heating with tandem differential mobility analyzer. Employing the rate expression used for sintering metallic and inorganic nanoparticles, it was found that the ease of coalescence varied with particle size. It was also suggested that the mechanism of coalescence may differ depending on the temperature. A model of coalescence kinetics based on crystallinity could not represent experimental coalescence kinetics. [Display omitted] • Estimation of coalescence rate constants for carbon nanoparticles. • Conventional formula greatly overestimates coalescing rate. • Coalescence was multi-staged, different mechanism from metal nanoparticles. [ABSTRACT FROM AUTHOR]