Shape Of Nanoparticles Research Articles

Efficientand Robust Automated Segmentation of Nanoparticles and Aggregates from Transmission Electron Microscopy Images with Highly Complex Backgrounds.

Morphologies of nanoparticles and aggregates play an important role in their properties for a range of applications. In particular, significant synthesis efforts have been directed toward controlling nanoparticle morphology and aggregation behavior in biomedical applications, as their size and shape have a significant impact on cellular uptake. Among several techniques for morphological characterization, transmission electron microscopy (TEM) can provide direct and accurate characterization of nanoparticle/aggregate morphology details. Nevertheless, manually analyzing a large number of TEM images is still a laborious process. Hence, there has been a surge of interest in employing machine learning methods to analyze nanoparticle size and shape. In order to achieve accurate nanoparticle analysis using machine learning methods, reliable and automated nanoparticle segmentation from TEM images is critical, especially when the nanoparticle image contrast is weak and the background is complex. These challenges are particularly pertinent in biomedical applications. In this work, we demonstrate an efficient, robust, and automated nanoparticle image segmentation method suitable for subsequent machine learning analysis. Our method is robust for noisy, low-electron-dose cryo-TEM images and for TEM cell images with complex, strong-contrast background features. Moreover, our method does not require any a priori training datasets, making it efficient and general. The ability to automatically, reliably, and efficiently segment nanoparticle/aggregate images is critical for advancing precise particle/aggregate control in biomedical applications.

New Fe3O4-Based Coatings with Enhanced Anti-Biofilm Activity for Medical Devices.

With the increasing use of invasive, interventional, indwelling, and implanted medical devices, healthcare-associated infections caused by pathogenic biofilms have become a major cause of morbidity and mortality. Herein, we present the fabrication, characterization, and in vitro evaluation of biocompatibility and anti-biofilm properties of new coatings based on Fe3O4 nanoparticles (NPs) loaded with usnic acid (UA) and ceftriaxone (CEF). Sodium lauryl sulfate (SLS) was employed as a stabilizer and modulator of the polarity, dispersibility, shape, and anti-biofilm properties of the magnetite nanoparticles. The resulting Fe3O4 functionalized NPs, namely Fe3O4@SLS, Fe3O4@SLS/UA, and Fe3O4@SLS/CEF, respectively, were prepared by co-precipitation method and fully characterized by XRD, TEM, SAED, SEM, FTIR, and TGA. They were further used to produce nanostructured coatings by matrix-assisted pulsed laser evaporation (MAPLE) technique. The biocompatibility of the coatings was assessed by measuring the cell viability, lactate dehydrogenase release, and nitric oxide level in the culture medium and by evaluating the actin cytoskeleton morphology of murine pre-osteoblasts. All prepared nanostructured coatings exhibited good biocompatibility. Biofilm growth inhibition ability was tested at 24 h and 48 h against Staphylococcus aureus and Pseudomonas aeruginosa as representative models for Gram-positive and Gram-negative bacteria. The coatings demonstrated good biocompatibility, promoting osteoblast adhesion, migration, and growth without significant impact on cell viability or morphology, highlighting their potential for developing safe and effective antibacterial surfaces.

Biosynthesis of gold nanoparticles by using gelatin as reducing and stabilizing agent under ultrasound irradiation: Application of its catalytic activity and for ameliorating motor recovery after spinal cord injury in the Wistar rat’s model

The current project describes the facile preparation of Au nanoparticles mediated by gelatin as a natural capping and reducing agent in mild condition. The formation of Au nanoparticles stabilized by gelatin (Au NPs/Gelatin) and structural characteristics were studied via UV–Vis, FT-IR, TEM, FE-SEM, EDX and elemental mapping techniques. The evidence shown that gelatin-capped gold nanoparticles resulted in the lowest average particle sizes of 15–25 nm and spherical shapes nanoparticles. Further, newly synthesized Au NPs/Gelatin are used as a nanocatalyst for the reduction of 4-nitrophenol (4-NP) dyes. A UV–Vis spectrophotometer is employed to track the effectiveness of the reduction process. Recyclability in six further degradation cycles is used to assess the sustainability of this catalyst, and the results show a steady and notable degradation activity. In the in vivo experiment, 60 male rats were classified into four groups: control, intact, sham, and Au NPs/Gelatin nanocatalyst (20 µg/kg) groups. The Hematoxylin and eosin staining was conducted to examine the post-injury lesions. Additionally, somatosensory evoked potential experiments were conducted to assess the recovery of neural conduction. The expression of GFAP was evaluated to determine the extent of astrogliosis. Furthermore, the behavioral outcomes of the rats were evaluated using the BBB scores on a weekly basis after the spinal cord injury onset. The results of the research demonstrated that the neuroprotective effects of Au NPs/Gelatin nanocatalyst led to an amelioration in the rat’s model. Electromyography (EMG) data revealed a remarkable amelioration in hindlimb function in the Au NPs/Gelatin nanocatalyst (20 µg/kg) group. The ventral motor neurons number significantly raised, while the cavity areas significantly decreased in the Au NPs/Gelatin group. Moreover, the expression of GFAP was notably reduced in the Au NPs/Gelatin nanocatalyst group. The Au NPs/Gelatin nanocatalyst group exhibited a significant reduction in delayed responses and a significant increase in BBB scores during sensory tests.

Hybrid Nanofluid Flow over a Shrinking Darcy-Forchheimer Porous Medium with Shape Factor and Solar Radiation: A Stability Analysis

This research aimed to develop a numerical solution to analyze the effects of solar radiation and nanoparticle shape factors on the flow of a hybrid nanofluid past a shrinking Darcy-Forchheimer porous medium. The base fluid chosen for this study is water (H2O), and the hybrid nanofluid consists of nanoparticles of silver (Ag) and titanium dioxide (TiO2) in four different shapes: bricks, cylinders, platelets, and blades. To account for solar radiation, the energy model incorporated a radiative heat flux, while the momentum problem considers the influence of a magnetic field. The application of an appropriate similarity transformation method converts the partial differential equations (PDEs) model into a system of nonlinear ordinary differential equations (ODEs). The mathematical model is solved using the shooting technique method and the bvp4c solver. The obtained results, along with the effects of the nanoparticle shape factor, solar radiation parameter, shrinking parameter, Darcy-Forchheimer number, and nanofluid volume fraction, are visually presented through figures and tables. It is worth noting that, in our numerical results, we observed the presence of dual solutions when λ < 0. Our findings indicate that the thermal transmittance increases with an increase in the nanoparticle shape factor and solar radiative parameter. Additionally, we observed an escalation in the velocity distribution in relation to the shrinking parameter and nanofluid volume fraction. Before reaching the two solutions, a flow stability analysis revealed that the first branch appears to be the most stable. Overall, these findings provide valuable insights into the behaviour of hybrid nanofluid flow in the presence of solar radiation and porous media.

Thermophoresis-Induced Polymer-Driven Destabilization of Gold Nanoparticles for Optically Directed Assembly at Interfaces.

The limitations of conventional template-based methods for the deposition of nanoparticle assemblies into defined patterns on solid substrates call for the development of techniques that do not require templates or lithographic masks. The use of optically-induced thermal gradients to drive the migration of colloids toward or away from a laser spot, known as opto-thermophoresis, has shown promise for the low-power trapping and optical manipulation of a variety of colloidal species. However, the printing of colloids using this technique has so far not been established. Herein, a method for the optically directed printing of noble metal nanoparticles, specifically gold nanospheres is reported. The thermophoresis of the polymer polyvinylpyrrolidone and gold nanospheres toward a laser spot led to the deposition of nanoparticle aggregates, capable of serving as surface-enhanced Raman scattering substrates. The influence of heating laser power and the concentrations of polymer, salt, and surfactant on the nanoparticle deposition rate and structure of the printed pattern are studied, showing that a variety of conditions can permit printing, suggesting facile generalization to different nanoparticle compositions, sizes, and shapes. These findings will greatly benefit future efforts for directed nanoparticle assembly, and drive applications in sensing, photothermal heating, and relevant applications in biomedicine and devices.

A comprehensive study of carbon nanoparticle shape and orientation effects on composite elastic properties using FEA

In this study, three critical parameters that influence the effective composite properties of Carbon nanoparticles were tested and modeled using finite elements through Digimat Finite Element Analysis (FEA) software, employing representative volume elements (RVE). The primary parameters under consideration are the fiber shape, fiber orientation, and fiber volume fraction. Four of the many different shapes of Carbon nanoparticles, namely Tubes, Disk, Sphere, and Cylinder, were investigated, coupled with four distinct orientations for tubes: horizontal, aligned at 45°, random, and vertical each varying in the carbon fiber volume fraction. The material of choice was pure epoxy resin because of the nature of the bonding between its two phases and its wide range of usage. Forces were applied along the X-axis, coupled with shear in the XY plane. This study revealed that the orientation of CNTs primarily influences the Elastic Young’s modulus, whereas the size of the CNTs has the main effect on the shear modulus, followed by orientation. The horizontal CNTs demonstrated superior Young’s modulus, but the random orientation had a more pronounced impact on the shear modulus variation. Regarding the analysis of the nanoparticles shapes, the disk shape with fixed orientation revealed the highest elastic modulus, after which the cylinder shape and the sphere recorded the minimum elastic modulus among the three studied shapes.

Expression of Concern for article entitled “Effect of nanoparticles shape on the cooling process of a lithium ion battery in geometry with capillary channels in the presence of phase change material”

Expression of Concern for article entitled “Effect of nanoparticles shape on the cooling process of a lithium ion battery in geometry with capillary channels in the presence of phase change material”

Sculpturing metal nanoparticles by controlled massive deformation

Controlling the shape and orientation of metal nanoparticles constitutes fundamental strategies employed to tune their distinctive properties. However, singular high-energy surfaces are notably missing from nanoparticles fabricated using existing synthesis techniques. In this work, we fabricated supported (111)-oriented Pt nanoparticles that expose low-energy surfaces and subsequently reshaped them using a metal forming technique. We found that the orientations of deformed particles span a continuum encompassing (111), (110) and (112) and observed a linear dependence of this re-orientation on the plastic strain. We proposed a model describing particle rotation during deformation in terms of synergistic interplay between slip and diffusion.

Multiple Fano Resonances Enabled by the Interference between an Out‐of‐Plane Plasmon Mode and Fabry–Pérot Cavity Modes

AbstractMultiple Fano resonances (mFRs) are arising as a promising optical platform to achieve precise sensing and detection. However, experimentally achieving mFRs by simple structures has remained challenging, which impedes the widespread applications of mFRs. Herein a simple structure composed of a single colloidal metal nanoparticle and a transition metal dichalcogenide flake to simultaneously achieve up to 8 FRs in experiments is demonstrated. Combining theoretical and experimental techniques, that an out‐of‐plane plasmon mode of the metal nanoparticle interferes with the Fabry–Pérot cavity modes from the WS2 flake to form mFRs in the visible region is proved. The simplicity and generality of the method further allow us to systematically study the tunability of the mFRs, in terms of the peak/dip positions and the number of FRs, by changing the structural parameters, which include the thickness of the WS2 flake, size and shape of the plasmonic nanoparticle. In addition, the quality of the mFRs is proved to be adjustable by tuning the reflectivity of the substrate in the system. The highest quality factor and spectral contrast of the achieved resonances are up to ≈180 and ≈0.95, respectively. The simple structure and high‐quality optical modes will prosper applications in precise sensing and light modulation.

Advanced properties of gold nanoparticles obtained by using long-chain secondary amine for phase transfer from water to chloroform

We have conducted a new comparison of gold nanoparticles functionalized by primary- and secondary amine with the same chain length. Our hypothesis suggests that the adaptive steric conformation of the secondary amine molecular branches makes a marked additional contribution to the well-established role of the ligand chain length. We characterize the importance of this factor based on diOctadecylamine (diODA) and Octadecylamine (ODA) passivated gold nanoparticles by using high-resolution transmission electron microscopy (HR-TEM) and selective area electron diffraction (SAED). The results evidenced that the diODA coordination to the inorganic core forms a more efficient and impenetrable protective coating. The SAED patterns show a more homogeneous distribution of the small crystalline domains in the gold core. TEM images show a smooth spherical shape of the diODA nanoparticles and a lack of interparticle coalescence cases. The diODA-passivation provides nanoparticles with nearly twice the effective ligand length than its ODA equivalent. This results in their spontaneous arrangement in domains with expressed crystal-like order despite the relatively large size-dispersity before passivation. The surface free energy of coatings, formed by diODA passivated gold nanoparticles, is twice as small as measured on the ODA-nanoparticle-coated surfaces.

Black seed assisted synthesis, characterization, free radical scavenging, antimicrobial and anti-inflammatory activity of iron oxide nanoparticles

Iron nanoparticles comprise a significant class of inorganic nanoparticles, which discover applications in various zones by prudence of their few exciting properties. This study achieved the green synthesis of iron oxide nanoparticles (IONPs) by black cumin seed (Nigella sativa) extract, which acts as a reducing and capping agent. The iron nanoparticles and black cumin extract were synthesized in three different concentrations: (01:01, 02:04,01:04). UV-visible spectroscopy, XRD, FTIR, and AFM characterized the synthesized iron oxide nanoparticles. UV-visible spectra show the maximum absorbance peak of 01:01 concentration at 380 nm. The other concentrations, such as 02:04, peaked at 400 nm and 01:04 at 680 nm, confirming the formation of iron oxide nanoparticles. AFM analysis reveals the spherical shape of iron oxide nanoparticles. The XRD spectra reveal the (fcc) cubic crystal structure of the iron oxide nanoparticles. The FTIR analysis’s peaks at 457.13, 455.20, and 457.13 cm-1 depict the characteristic iron nanoparticle synthesis. The black cumin extract-mediated iron oxide nanoparticles show substantial antibacterial, antifungal, antioxidant and anti-inflammatory activity in a dose-dependent manner.

Study on Synthesis and Characterization of Metal Nanoparticles for Biomedical Applications

In this research paper, I have thoroughly described about the topic “Study on Synthesis and Characterization of Metal Nanoparticles for Biomedical Applications.” Metal nanoparticles have emerged as promising candidates for a myriad of biomedical applications due to their unique physicochemical properties, offering a wide array of opportunities for innovation in healthcare. This abstract discusses metal nanoparticle creation, characterization, and biomedical applications. Chemical reduction, green synthesis, physical deposition, and biological methods allow fine nanoparticle size, shape, and composition control for biomedical applications. TEM, DLS, XRD, UV-Vis, FTIR, SEM, and TGA reveal metal nanoparticles' structural, chemical, and optical properties. Metal nanoparticles are used in medication delivery, imaging contrast, targeted therapy, and diagnostics. Their small size, large surface area-to-volume ratio, and tunable optical properties make them suitable for drug delivery, where they can encapsulate and release therapeutic substances at precise body regions. Metal nanoparticles also improve illness identification and monitoring in MRI, CT, and fluorescence imaging by acting as contrast agents. They provide innovative cancer and microbial infection treatments due to their photothermal and antibacterial characteristics. Metal nanoparticles also find utility in biosensing applications, facilitating the detection of biomolecules and disease biomarkers with high sensitivity and specificity. Overall, the synthesis and characterization of metal nanoparticles represent a vibrant area of research with significant implications for advancing healthcare technologies, offering versatile platforms for addressing key challenges in diagnostics, therapeutics, and imaging in biomedicine.

Biomimetic Fe-bearing nanoparticles in hot spring: morphology, origin and potential bioavailable Fe

Iron is a critical redox-active element in geothermal water, and the presence of nanoparticulate Fe is essential in comprehending the intricate cycling of iron and related elements within the natural geothermal ecosystems. In this study, we investigated the mineral properties of Fe-bearing nanoparticles in a hot spring located in Shanxi Province. High-resolution transmission electron microscopy (HRTEM) is utilized for the examination of the morphology, chemical composition, and crystalline structure of Fe-bearing nanoparticles. The findings show that Fe-bearing nanoparticles can exist as single particles measuring 50–200 nm in size, as well as aggregate to form nanoparticle aggregations. The morphology of Fe-bearing nanoparticles mainly includes triangle, axiolitic, and irregular shapes. The selected area electron diffraction patterns reveal the crystal form, amorphous form, and the transition from amorphous to crystalline forms of these nanoparticles. Energy-dispersive X-ray spectroscopy (EDS) analysis indicates that these nanoparticles primarily consist of O and Fe in composition, along with various trace elements including N, Al, Si, Ca, Zn, Cr, Ni, and Mo. These results reveal that goethite and hematite can occur in hot spring. Various in size and modality, tend to cluster into each other, and multiple crystalline states indicate that these iron-bearing nanoparticles are formed through natural processes. In addition, the iron-bearing nanoparticles with biomimetic morphologies (cell-like or microorganism-like shapes) may be produced through microbial activity. The biomimetic properties also imply that these nanoparticles may be readily available for biological processes. Significantly, our findings further validate that the shape of iron oxide nanoparticles can serve as an indicator of pH and temperature of the hot spring.

Electrical and Dielectric Properties of Polymer-Metal Hybrid Nanocomposites - A Short Review

Polymer-metal hybrid nanocomposites have garnered significant attention in recent years due to their exceptional electrical and dielectric properties, which find applications in a wide range of industries, including electronics, energy storage, and advanced materials. This review article provides a comprehensive overview of the current state-of-the-art in the field of polymer-metal hybrid nanocomposites, with a particular focus on their electrical and dielectric properties. The first section of the review delves into the synthesis and fabrication techniques employed to create these nanocomposites, highlighting the importance of controlling the dispersion and distribution of metal nanoparticles within the polymer matrix. Various approaches, such as in-situ polymerization, melt mixing, and electrospinning, are discussed in detail, along with their respective advantages and limitations.The subsequent sections explore the influence of metal nanoparticles on the electrical conductivity and dielectric constant of the nanocomposites. The role of factors such as nanoparticle size, shape, and concentration in determining these properties is thoroughly examined. Moreover, the impact of metal surface modifications and the choice of polymer matrix on enhancing electrical and dielectric performance are also addressed. In addition to discussing fundamental aspects, this review highlights practical applications of polymer-metal hybrid nanocomposites in the development of high-performance capacitors, sensors, electromagnetic shielding materials, and flexible electronics. The potential for these materials to revolutionize various technological sectors is discussed, emphasizing their role in advancing miniaturization, energy efficiency, and durability. Furthermore, the review outlines current challenges and future prospects in the field, including the need for a deeper understanding of the underlying mechanisms governing electrical and dielectric behavior in these nanocomposites. Emerging trends such as the incorporation of 2D materials and the development of multifunctional hybrid systems are also explored, hinting at exciting avenues for further research and innovation. In conclusion, polymer-metal hybrid nanocomposites offer a promising platform for tailoring electrical and dielectric properties to meet the demands of modern technology. This review serves as a valuable resource for researchers, engineers, and scientists seeking to explore the potential of these materials and drive advancements in the field of electrical and dielectric engineering.

On the thermal performance of radiative stagnation-point hybrid nanofluid flow across a wedge with heat source/sink effects and sensitivity analysis

The present article aims to examine the thermal performance and the sensitivity analysis of a GO−TiO2/water hybrid nanofluid in the presence of different nanoparticle shapes along with heat absorption and thermal radiation effects over a wedge geometry. Analyzing the effects of heat generation and radiation effects is one of the key studies conducted by researchers in various nanofluid flows over some required geometries. However, a combined study of these effects has yet to be studied over a moving wedge, and that combination defines the novelty of the work. Similarity transformations are implemented to the governing equations to obtain the final set of nondimensional equations, which are solved using the bvp4c code in MATLAB. The results obtained were in close agreement with the published results. The Nusselt number decreased with an increase in the heat source parameter Q, and it increased with an increasing Hartree pressure gradient β and thermal radiation parameter Rd. The sensitivity is statistically analyzed for the variations in radiation effect, heat source, and pressure gradient parameters on the Nusselt number. The high values for R2=99.99% and Adj R2=99.96% validate the ANOVA results obtained using a Box–Behnken design (BBD) model in the response surface methodology (RSM) with 14 degrees of freedom. The input parameters Rd and β show positive sensitivity, while Q shows negative sensitivity toward the skin friction. The Nusselt number proves to be most sensitive toward the pressure gradient parameter. TiO2, graphene (Gr), and the derivative forms of graphene, are gaining much importance due to their wide applications in the oil and petroleum industries. Thus, this study contributes to lubrication purposes, emulsion stabilizers, oxalic acid removal, anti-corrosive properties, etc.

MHD radiating flow in a hybrid solution of C2H6O2–H2O to disperse Ag–Al2O3 hybrid nanoparticles taking into account the effects of nanoparticle shapes

MHD radiating flow in a hybrid solution of C2H6O2–H2O to disperse Ag–Al2O3 hybrid nanoparticles taking into account the effects of nanoparticle shapes

Isolation and Characterization of Spherical Cellulose Nanocrystals Extracted from the Higher Cellulose Yield of the Jenfokie Plant: Morphological, Structural, and Thermal Properties.

Scholars are looking for solutions to substitute hazardous substances in manufacturing nanocellulose from bio-sources to preserve the world's growing environmental consciousness. During the past decade, there has been a notable increase in the use of cellulose nanocrystals (CNCs) in modern science and nanotechnology advancements because of their abundance, biocompatibility, biodegradability, renewability, and superior mechanical properties. Spherical cellulose nanocrystals (J-CNCs) were successfully synthesized from Jenfokie micro-cellulose (J-MC) via sulfuric acid hydrolysis in this study. The yield (up to 58.6%) and specific surface area (up to 99.64 m2/g) of J-CNCs were measured. A field emission gun-scanning electron microscope (FEG-SEM) was used to assess the morphology of the J-MC and J-CNC samples. The spherical shape nanoparticles with a mean nano-size of 34 nm for J-CNCs were characterized using a transmission electron microscope (TEM). X-ray diffraction (XRD) was used to determine the crystallinity index and crystallinity size of J-CNCs, up to 98.4% and 6.13 nm, respectively. The chemical composition was determined using a Fourier transform infrared (FT-IR) spectroscope. Thermal characterization of thermogravimetry analysis (TGA), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) was conducted to identify the thermal stability and cellulose pyrolysis behavior of both J-MC and J-CNC samples. The thermal analysis of J-CNC indicated lower thermal stability than J-MC. It was noted that J-CNC showed higher levels of crystallinity and larger crystallite sizes than J-MC, indicating a successful digestion and an improvement of the main crystalline structure of cellulose. The X-ray diffraction spectra and TEM images were utilized to establish that the nanocrystals' size was suitable. The novelty of this work is the synthesis of spherical nanocellulose with better properties, chosen with a rich source of cellulose from an affordable new plant (studied for the first time) by stepwise water-retted extraction, continuing from our previous study.

A sustainable green synthesis for photocatalytic and antibacterial activity of zinc oxide nanoparticles using Cucumis maderaspatanus leaf extract

This study investigated the synthesis and photocatalytic activity of zinc oxide (ZnO) nanoparticles (NPs) at room temperature (ZnO-RT), 60° C (ZnO-60), and ultra sonication (ZnO-US). The NPs were made from Cucumis maderaspatanus (Cm) extract. ZnO NP sizes and shapes were observed to be influenced by synthesis conditions, as demonstrated by characterization techniques includes scanning electron microscopic analysis (SEM) and Fourier Transform Infra Red analysis (FTIR). The heated (60 °C) and ultra sonication (US) conditions produced NPs with diameters in the range of 15–25 nm with spherical shapes, while the non-heated (RT) condition produced NPs with diameters in the range of 20–30 nm with a mixture of spherical and flower shapes confirmed by SEM. Additionally, the presence of the reducing agents in the herbal extract was verified by analysing the FTIR spectra of the extract obtained after the synthesis. By using Coomassie Brilliant Blue R-250 (CBB-R-250) (50 ppm) as a probe molecule and subjecting it to UVA irradiation (λ = 356 nm), photocatalytic activity was measured. The results showed that ZnO-US reached 100 % degradation after 120 min and 90 % of the pollutant was mineralized, while ZnO-60 and ZnO-RT showed results of 80 % and 48 %, respectively. According to this study, the biological synthesis of NPs using plant extracts can be considered as a cost-effective and efficient method of biological synthesis of NPs and it could be an appropriate replacement to typical chemical methods for the synthesis of NPs.

Melting heat transfer and entropy analysis of ternary Casson nanofluids flow with second slip conditions: Application on rocket engine cooling

Heat transfer analysis of Casson nanofluid flow with single and multi-walled carbon nanotubes and Al2O3 or GO nanoparticles, which are suspended in kerosene oil, is elucidated. The impact of second slip conditions on the flow system’s velocity, temperature, and solutal is considered, along with the effect of melting heat transfer and nanoparticle shape factor. The appraisal’s novelty is the incorporation of second slip conditions on kerosene oil flow containing with new three distinct nanoparticles. Similar variables are used to convert the governing equations into ordinary equations which are then solved using homotopy perturbation method (HPM). The profiles of velocity, temperature, concentration, and Bejan number are estimated for various values of relevant parameters. Results demonstrate that the Bejan number declines due to enhance the first thermal parameter and second velocity parameter, while the contrary tendency is examined by raising the Casson fluid parameter and first velocity parameter. Al2O3-SWCNT-MWCNT TNF responds more strongly than GO-SWCNT-MWCNT TNF when the temperature is coupled with (nanoparticles volume fraction, first thermal parameter), axial velocity with (nanoparticles volume fraction, first velocity parameter, first thermal parameter), and Bejan number with melting parameter. This study is to help rocket engine designers identify the optimal nanofluids for cooling and fuel.

Photovoltaic parameters improvement via size control of monodisperse Mie-resonant nanoparticles in perovskite solar cells

Optically resonant Mie-resonant nanoparticles are powerful tools for light control at the nanoscale, which have been employed for such applications as coloration, and metaoptics, where the size and shape of nanoparticle play a critical role in the device performance. Moreover, such nanoparticles are successfully used for the improvement of perovskite solar cells. However, there is a lack of experimental knowledge on how the size of Mie-resonant nanoparticles affects the improvement of parameters in the photovoltaic devices. Here we apply monodisperse silicon nanoparticles to investigate optical effects responsible for the improvement of perovskite solar cells. The experimental analysis shows that the most optimal sizes of silicon nanoparticles for the perovskite with bandgap 1.53 eV are in the range 140–160 nm. The main reason for such improvement is the optimization of absorption in the perovskite layer around wavelength 500–800 nm, where the Mie resonances in nanoparticles are not completely damped but contribute to additional light trapping and scattering. Our results can be useful not only for further optimization of perovskite solar cells, but also pave the way for improvement of a broader range of photovoltaic devices with integrated Mie-resonant nanoparticles.