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1.
Food Chem ; 457: 139843, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38955120

ABSTRACT

Dried-bonito (Katsuobushi) exhibits a unique uniform "glass-like" texture after traditional smoke-drying. Herein, we developed a novel processing method for dried-bonito and elucidated the mechanism of transformation of loose muscle into a "glass-like" texture in terms of texture, microstructure, and protein properties. Our findings showed that the unfolding and aggregation of proteins after thermal induction was a key factor in shaping the "glass-like" texture in bonito muscle. During processing, myofibrils aggregated, the originally alternating thick and thin filaments contracted laterally and aligned into a straight line, and protein cross-linking increased. Secondary structural analysis revealed a reduction in unstable ß-turn content from 26.28% to 15.06%. Additionally, an increase in the content of SS bonds was observed, and the conformation changed from g-g-t to a stable g-g-g conformation, enhanced protein conformational stability. Taken together, our findings provide a theoretical basis for understanding the mechanism of formation of the uniform "glass-like" texture in dried-bonito.

2.
ACS Nano ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976597

ABSTRACT

Supported nonprecious metal catalysts such as copper (Cu) are promising replacements for Pt-based catalysts for a wide range of energy-related electrochemical reactions. Direct electrochemical deposition is one of the most straightforward and versatile methods to synthesize supported nonprecious metal catalysts. However, further advancement in the design of supported nonprecious metal catalysts requires a detailed mechanistic understanding of the interplay between kinetics and thermodynamics of the deposition phenomena under realistic reaction conditions. Here, we study the electrodeposition of Cu on carbon nanotubes and graphene derivatives under electrochemical conditions using in situ liquid cell transmission electron microscopy (TEM). By combining real-time imaging, electrochemical measurements, X-ray photoelectron spectroscopy (XPS), and finite-element analysis (FEA), we show that low-dimensional support materials, especially carbon nanotubes, are excellent for generating uniform and finely dispersed platinum group metal-(PGM)-free catalysts under mild electrochemical conditions. The electrodeposited Cu on graphene and carbon nanotubes is also observed to show good electrochemical activity toward nitrate reduction reactions (NO3RRs), further supported by density functional theory (DFT) calculations. Nitrogen doping plays an important role in guiding nonprecious metal deposition, but its low electrical conductivity may give rise to lower NO3RR activity compared to its nondoped analogue. The development of supported nonprecious metals through interfacial and surface engineering for the design of supported catalysts will substantially reduce the demand for precious metals and generate robust catalysts with better durability, thereby presenting opportunities for solving the critical problems in energy storage and electrocatalysis.

3.
Environ Res ; : 119568, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38971357

ABSTRACT

The aim of this study was to synthesize effective and economical MoS2/CdNi@rGO photocatalysts and investigate their performance in the degradation of organic pollutants in synthetic effluent. The objective was to assess the characterization results of the synthesized photocatalysts using XRD, SEM/EDS, TEM/HR-TEM, Raman spectrum, and BET isotherm analysis tools. These analyses revealed the good adhesion of MoS2 with rGO and provided insights into the structure and properties of the materials. The results showed that the MoS2/CdNi@rGO photocatalysts exhibited remarkable degradation efficiency for organic pollutants such as Rhodamine-B, erichrome black, and malachite green. The outcomes of the study demonstrated that the MoS2/CdNi@rGO catalyst had the greatest rate constant for Rhodamine-B (RhB) decomposition. which would have been approximately 33 times higher than that of pure RGO (0.0121 min-1). The MoS2/CdNi@rGO photocatalysts also showed excellent recyclability and persistence across five recycle assays, indicating their potential for practical applications in wastewater treatment. The photocatalyst was moderately active, stable up to its fifth usage and stability of the photocatalyst before and after the photocatalytic reaction was also been studied using XRD and SEM. Further research in this area could lead to the development of advanced photocatalytic technologies for environmental remediation.

4.
Methods Enzymol ; 700: 329-348, 2024.
Article in English | MEDLINE | ID: mdl-38971605

ABSTRACT

As the primary products of lipid oxidation, lipid hydroperoxides constitute an important class of lipids generated by aerobic metabolism. However, despite several years of effort, the structure of the hydroperoxidized bilayer has not yet been observed under electron microscopy. Here we use a 200 kV Cryo-TEM to image small unilamellar vesicles (SUVs) made (i) of pure POPC or SOPC, (ii) of their pure hydroperoxidized form, and (iii) of their equimolar mixtures. We show that the challenges posed by the determination of the thickness of the hydroperoxidized bilayers under these observation conditions can be addressed by an image analysis method that we developed and describe here.


Subject(s)
Cryoelectron Microscopy , Lipid Bilayers , Phosphatidylcholines , Unilamellar Liposomes , Lipid Bilayers/chemistry , Lipid Bilayers/metabolism , Cryoelectron Microscopy/methods , Unilamellar Liposomes/chemistry , Unilamellar Liposomes/metabolism , Phosphatidylcholines/chemistry , Oxidation-Reduction , Image Processing, Computer-Assisted/methods , Lipid Peroxides/chemistry , Lipid Peroxides/analysis
5.
J Phys Condens Matter ; 36(40)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38955334

ABSTRACT

In the wafer-scale growth of Ir(001) on yttria-stabilized zirconia (YSZ) by magnetron sputtering epitaxy two kinds of {111} oriented domains are observed. One consists of sharp 'fjord'-shaped features in which four 90° alternated rotational variants of {111} are possible and the second one consists of islands with less defined shapes in which eight 45° alternated rotational variants can be found. Their formation occurs directly at the Ir/YSZ interface along incoherent grain boundaries, likely nucleating at local defects of the YSZ surface. In order to avoid these misoriented domains, process separation and proper etching pretreatment of the wafers both before and between the sputtering processes have been found to be the key strategy for achieving reproducibility and overall better material quality.

6.
Plant Physiol Biochem ; 214: 108882, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38972244

ABSTRACT

Silver (Ag) is a non-essential heavy metal with substantial environmental toxicity but an excellent promotor for plant organogenesis. It is used as an elicitor for secondary metabolite production and for in planta synthesis of metal nanoparticles (MNPs). In the present study, the Ag accumulation and reduction capability of in vitro shoots of Withania somnifera and the toxicity and elicitation effect of Ag on in vitro shoots were explored. In vitro shoot cultures of W. somnifera were treated with different concentrations of silver nitrate for a specific treatment period. Growth index, withaferin A, elemental and electron microscopy analyses were done on silver-treated in vitro shoots of W. somnifera. 1 mM silver nitrate treatment for 12 days period was found to give increased growth index (1.425 ± 0.05c) and withaferin A (2.568 ± 0.08e mg g-1) content. The concentration of bioaccumulated Ag in 1 mM silver nitrate treated in vitro shoot was found to be 50.8 ppm. The presence of nano-Ag was also found in the leaves of 1 mM silver nitrate-treated in vitro shoots. In summary, this is the first report portraying the bioaccumulation and in planta reduction capability of the in vitro shoot system of W. somnifera, which makes it a potential medicinal plant of commercial value for silver contaminated soils.

7.
Dokl Biochem Biophys ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38955916

ABSTRACT

We performed a detailed ultrastructural reconstruction of the "passive" miracidium of Derogenes varicus Muller, 1784 , a species from Hemiurata group. The miracidium is highly miniaturized and simplified in comparison with the "active" miracidia. For the first time we elucidate the nature of the spines on the surface of hemiuroid larva: they are derivatives of the epithelial plates. The anterior end of the larva is equipped with three epithelial plates that bear both spines and cilia. The major part of the miracidial surface is formed by tegument. The nervous and excretory systems of the D. varicus miracidium are extremely reduced. Single undifferentiated cell comprises the germinal material of the miracidium. We discuss the trends of evolution of hemiuroid miracidia that are associated with transition to passive strategy of infection.

8.
J Invertebr Pathol ; 206: 108160, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38925365

ABSTRACT

The production demand of edible snails in the Mediterranean area is very high and the attention to snail borne diseases is increasing. Following mass mortality events, we have analyzed 240 samples of Cornu aspersum collected from farms across Italy. Anatomopathological examination showed the presence of alterations of the gastro-intestinal apparatus and of the digestive gland, while histopathological examination revealed the presence of Rickettsia-like organisms (RLOs) in 70% (168/240) of cases and Giemsa positive amoebae in the remaining 30% (72/240) of cases. RLOs were localized mainly at the level of the DG, where regressive changes or nodular inflammation was observed. TEM examination of RLOs samples revealed the presence of many rod-shaped electron dense microorganisms. Amoebal infection occurred in the kidney, intestine, lung, the DG and were associated to regressive events or infiltrative/nodular and encapsulation like inflammation. To date it is still unclear if the pathogens detected could represent a risk for humans and animals, therefore further studies are needed to better elucidate this point.

9.
Animals (Basel) ; 14(12)2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38929396

ABSTRACT

The purpose of this study was to analyze the ultrastructure of the testes of sexually immature calves and reproductive bulls of the Polish Holstein-Friesian Black-and-White breed. Utilizing TEM, this study identified three distinct stages of seminiferous tubule development in calves, characterized by varying shapes, distributions, and arrangements of individual cells. In immature animals, early developing spermatocytes, prespermatogonia, and pre-Sertoli cells were observed within the seminiferous tubules. In sexually mature bulls, all cells of the spermatogenic series were observed, situated on a thin, multilayered basal lamina, which forms characteristic undulations. An abundant smooth endoplasmic reticulum was observed in the cytoplasm of spermatogonia in both groups of animals, forming characteristic membranous swirls. In adult bulls, spermatogonia maintain contact with each other through numerous cytoplasmic bridges and cell connections, forming small spaces with visible microvilli between them. The ultrastructural analysis facilitated the identification of morphological changes occurring during the maturation of pre-Sertoli cells, transitioning from a large euchromatic nucleus to a nucleus in which the formation of characteristic vesicles and tubules could be observed. It should also be emphasized that two types of Sertoli cells, namely dark and light electron-dense cells, can be found in cattle. These cells differ from each other, indicating that they may perform different functions. The widespread recognition of the presence of two types of Sertoli cells in cattle will undoubtedly contribute to a better understanding of the processes occurring within the testes and provide a basis for further research in this area.

10.
Micron ; 185: 103678, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38941681

ABSTRACT

The rich potential of two-dimensional materials endows them with superior properties suitable for a wide range of applications, thereby attracting substantial interest across various fields. The ongoing trend towards device miniaturization aligns with the development of materials at progressively smaller scales, aiming to achieve higher integration density in electronics. In the realm of nano-scaling ferroelectric phenomena, numerous new two-dimensional ferroelectric materials have been predicted theoretically and subsequently validated through experimental confirmation. However, the capabilities of conventional tools, such as electrical measurements, are limited in providing a comprehensive investigation into the intrinsic origins of ferroelectricity and its interactions with structural factors. These factors include stacking, doping, functionalization, and defects. Consequently, the progress of potential applications, such as high-density memory devices, energy conversion systems, sensing technologies, catalysis, and more, is impeded. In this paper, we present a review of recent research that employs advanced transmission electron microscopy (TEM) techniques for the direct visualization and analysis of ferroelectric domains, domain walls, and other crucial features at the atomic level within two-dimensional materials. We discuss the essential interplay between structural characteristics and ferroelectric properties on the nanoscale, which facilitates understanding of the complex relationships governing their behavior. By doing so, we aim to pave the way for future innovative applications in this field.

11.
Phys Med Biol ; 69(13)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38870999

ABSTRACT

Objective.The availability of magnetic nanoparticles (MNPs) with medical approval for human intervention is fundamental to the clinical translation of magnetic particle imaging (MPI). In this work, we thoroughly evaluate and compare the magnetic properties of an magnetic resonance imaging (MRI) approved tracer to validate its performance for MPI in future human trials.Approach.We analyze whether the recently approved MRI tracer Resotran is suitable for MPI. In addition, we compare Resotran with the previously approved and extensively studied tracer Resovist, with Ferrotran, which is currently in a clinical phase III study, and with the tailored MPI tracer Perimag.Main results.Initial magnetic particle spectroscopy (MPS) measurements indicate that Resotran exhibits performance characteristics akin to Resovist, but below Perimag. We provide data on four different tracers using dynamic light scattering, transmission electron microscopy, vibrating sample magnetometry measurements, MPS to derive hysteresis, point spread functions, and a serial dilution, as well as system matrix based MPI measurements on a preclinical scanner (Bruker 25/20 FF), including reconstructed images.Significance.Numerous approved MNPs used as tracers in MRI lack the necessary magnetic properties essential for robust signal generation in MPI. The process of obtaining medical approval for dedicated MPI tracers optimized for signal performance is an arduous and costly endeavor, often only justifiable for companies with a well-defined clinical business case. Resotran is an approved tracer that has become available in Europe for MRI. In this work, we study the eligibility of Resotran for MPI in an effort to pave the way for human MPI trials.


Subject(s)
Magnetic Resonance Imaging , Magnetic Resonance Imaging/methods , Humans , Magnetite Nanoparticles/chemistry
12.
Ultrastruct Pathol ; : 1-15, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916264

ABSTRACT

Glioblastoma tumors are the most aggressive primary brain tumors that develop resistance to temozolomide (TMZ). Eribulin (ERB) exhibits a unique mechanism of action by inhibiting microtubule dynamics during the G2/M cell cycle phase. We utilized the T98G human glioma cell line to investigate the effects of ERB and TMZ, both individually and in combination. The experimental groups were established as follows: control, E5 (5 nM ERB), T0.75 (0.75 mM TMZ), T1 (1.0 mM TMZ), and combination groups (E5+T0.75 and E5+T1). All groups showed a significant decrease in cell proliferation. Apoptotic markers revealed a time-dependent increase in annexin-V expression, across all treatment groups at the 48-hour time point. Caspase-3, exhibited an increase in the combination treatment groups at the 48-hour mark. Transmission electron microscopy (TEM) revealed normal ultrastructural features in the glioma cells of the control group. However, treatments induced ultrastructural changes within the spheroid glioblastoma model, particularly in the combination groups. These changes included a dose-dependent increase in autophagic vacuoles and apoptotic morphology of the cells. In conclusion, the similarity in the mechanism of action between ERB and TMZ suggests the potential for synergistic effects when combined. Our results highlight that this combination induced severe damage and autophagy in glioma spheroids after 48 hours.

13.
J Appl Microbiol ; 135(6)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38877639

ABSTRACT

AIM: Coaggregation, a highly specific cell-cell interaction mechanism, plays a pivotal role in multispecies biofilm formation. While it has been mostly studied in oral environments, its occurrence in aquatic systems is also acknowledged. Considering biofilm formation's economic and health-related implications in engineered water systems, it is crucial to understand its mechanisms. Here, we hypothesized that traceable differences at the proteome level might determine coaggregation ability. METHODS AND RESULTS: Two strains of Delftia acidovorans, isolated from drinking water were studied. First, in vitro motility assays indicated more swarming and twitching motility for the coaggregating strain (C+) than non-coaggregating strain (C-). By transmission electronic microscopy, we confirmed the presence of flagella for both strains. By proteomics, we detected a significantly higher expression of type IV pilus twitching motility proteins in C+, in line with the motility assays. Moreover, flagellum ring proteins were more abundant in C+, while those involved in the formation of the flagellar hook (FlE and FilG) were only detected in C-. All the results combined suggested structural and conformational differences between stains in their cell appendages. CONCLUSION: This study presents an alternative approach for identifying protein biomarkers to detect coaggregation abilities in uncharacterized strains.


Subject(s)
Biofilms , Drinking Water , Flagella , Proteomics , Biofilms/growth & development , Drinking Water/microbiology , Flagella/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Adhesion , Fimbriae, Bacterial/metabolism , Water Microbiology , Proteome
14.
Insects ; 15(6)2024 May 31.
Article in English | MEDLINE | ID: mdl-38921118

ABSTRACT

The mandibles are among the most important appendages of insects' mouthparts. Their morpho-functional organization is correlated with the variation in dietary preferences. In this study, we investigated the ultrastructural organization and metal composition of the mandibles of two ladybird species with different dietary habits: Harmonia axyridis (an entomophagous species) and Subcoccinella vigintiquatuorpunctata (a phytophagous species). The ultrastructural organization was studied using Scanning and Transmission Electron Microscopy, whereas the metal composition was investigated using Energy-Dispersive X-ray spectroscopy (EDX). Significant differences were observed in the general organization and metal enrichment pattern between the two species. The mandibles of H. axyridis are large and present a molar part with two teeth, with the apical one showing a bifid apex. In contrast, S. vigintiquatuorpunctata exhibited a molar region with several teeth on its apical part. The study revealed significant differences in metal content between the teeth and the prostheca of H. axyridis. Mn was the most abundant element in teeth, whereas Cl was more abundant in the prostheca. In the case of S. vigintiquatuorpunctata, Si was the most abundant element in the prostheca, while Mn was more present in the teeth. A comparison between the two species revealed that both teeth and prostheca showed significant variation in the elemental composition. These findings underscore the role of dietary preferences in shaping the structural and metal composition variations in the mandibles of these two ladybird species.

15.
Nanomaterials (Basel) ; 14(12)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38921917

ABSTRACT

The hexagonal ferrite h-YbFeO3 grown on YSZ(111) by pulsed laser deposition is foreseen as a promising single multiferroic candidate where ferroelectricity and antiferromagnetism coexist for future applications at low temperatures. We studied in detail the microstructure as well as the temperature dependence of the magnetic properties of the devices by comparing the heterostructures grown directly on YSZ(111) (i.e., YbPt_Th0nm) with h-YbFeO3 films deposited on substrates buffered with platinum Pt/YSZ(111) and in dependence on the Pt underlayer film thickness (i.e., YbPt_Th10nm, YbPt_Th40nm, YbPt_Th55nm, and YbPt_Th70nm). The goal was to deeply understand the importance of the crystal quality and morphology of the Pt underlayer for the h-YbFeO3 layer crystal quality, surface morphology, and the resulting physical properties. We demonstrate the relevance of homogeneity, continuity, and hillock formation of the Pt layer for the h-YbFeO3 microstructure in terms of crystal structure, mosaicity, grain boundaries, and defect distribution. The findings of transmission electron microscopy and X-ray diffraction reciprocal space mapping characterization enable us to conclude that an optimum film thickness for the Pt bottom electrode is ThPt = 70 nm, which improves the crystal quality of h-YbFeO3 films grown on Pt-buffered YSZ(111) in comparison with h-YbFeO3 films grown on YSZ(111) (i.e., YbPt_Th0nm). The latter shows a disturbance in the crystal structure, in the up-and-down atomic arrangement of the ferroelectric domains, as well as in the Yb-Fe exchange interactions. Therefore, an enhancement in the remanent and in the total magnetization was obtained at low temperatures below 50 K for h-YbFeO3 films deposited on Pt-buffered substrates Pt/YSZ(111) when the Pt underlayer reached ThPt = 70 nm.

16.
Nanotechnology ; 35(38)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38838651

ABSTRACT

Vertically aligned ZnO nanorods (NRs) were grown hydrothermally on the wide bandgap (∼3.86 - 4.04 eV) seed layers (SLs) of grain size ∼162 ± 35 nm, prepared using ball-milled derived ZnO powder. The synthesized ZnO NRs were further decorated with ZnS nanocrystals to achieve a ZnO NR-ZnS core-shell (CS)-like nano-scaffolds by a subsequent hydrothermal synthesis at 70 °C for 1 h. UV-Vis-NIR spectroscopy, x-ray diffractometry (XRD), Raman spectroscopy and Field emission scanning electron microscopy (FESEM) coupled with Energy dispersive x-ray spectroscopy (EDX) analyses confirmed the formation of ZnS atop the vertically aligned ZnO NR arrays of ∼1.79 ± 0.17µm length and ∼165 ± 27 nm diameter. Transmission electron microscopy (TEM)/EDX analyses revealed that vertically aligned ZnO NRs (core dia. ∼181 ± 12 nm) arrays are conformally coated by an ultrathin ZnS (∼25 ± 7 nm) shell layer with a preferential ZnS{111}/ZnO{10-10}-like partial epitaxy. The ZnO NRs exhibited a sharp band edge near ∼384 nm having optical bandgap energy (Eg) of ∼3.23 eV. However, the ZnO NR-ZnS CS exhibited double absorption bands atEg∼ 3.20 eV (ZnO-core) andEg∼ 3.78 eV (ZnS-shell). The ZnS{111}/ZnO{10-10}-nano-scaffolds could be utilized to facilitate the enhanced absorption of UV photons as well as the radial junction formation between the Pb-free perovskite absorber and ZnS/ZnO NRs layers.

17.
J Pharm Bioallied Sci ; 16(Suppl 2): S1522-S1525, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38882886

ABSTRACT

Introduction: The synaptic contacts play an important role in central nervous system (CNS) functioning. Ultrastructural features of synapses in CNS are not studied in naphthalene neurotoxicity model. Materials and Methodology: In the present work, transmission electron microscopy was used for studying the ultrastructural features of synapses in the hippocampus of Sprague Dawley rat brain, on subsequent exposure to naphthalene balls. The ultrastructural changes were observed for naphthalene low dose (200 mg), high dose (400 mg) after the treatment for 28 days, and post-delayed toxicity phase after 14 days in Sprague Dawley rats. Results: In comparison with different groups of naphthalene exposure including control and satellite, axon degeneration, axonal demyelination and abnormal synapses was observed in high dose naphthalene administration group. In the post-delayed naphthalene toxicity group, degeneration of synaptic contacts was observed. Conclusions: This exploration of ultrastructural variations in the synapses of Hippocampus gives information that will be valued in naphthalene neurotoxicological research.

18.
Nano Lett ; 2024 Jun 02.
Article in English | MEDLINE | ID: mdl-38825790

ABSTRACT

The core task of neuromorphic devices is to effectively simulate the behavior of neurons and synapses. Based on the functionality of ferroelectric domains with the advantages of low power consumption and high-speed response, great progress has been made in realizing neuromimetic behaviors such as ferroelectric synaptic devices. However, the correlation between the ferroelectric domain dynamics and neuromimetic behavior remains unclear. Here, we reveal the correlation between domain/domain wall dynamics and neuromimetic behaviors from a microscopic perspective in real-time by using high temporal and spatial resolution in situ transmission electron microscopy. Furthermore, we propose utilizing ferroelectric microstructures for the simultaneous simulation of neuronal and synaptic plasticity, which is expected to improve the integration and performance of ferroelectric neuromorphic devices. We believe that this work to study neuromimetic behavior from the perspective of domain dynamics is instructive for the development of ferroelectric neuromorphic devices.

19.
Microsc Res Tech ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38856214

ABSTRACT

Field emission finds a vital space in numerous scientific and technological applications, including high-resolution imaging at micro- and nano-scales, conducting high-energy physics experiments, molecule ionization in spectroscopy, and electronic uses. A continuous effort exists to develop new materials for enhanced field emission applications. In the present work, two-dimensional (2D) well-aligned CdSSe flake flowers (CdSSe-FFs) were successfully grown on gold-coated silicon substrate utilizing a simple and affordable chemical bath deposition approach at ambient temperature. The time-dependent growth mechanism from nanoparticles to FFs was observed at optimized parameters such as concentration of precursors, pH (~11), deposition time, and solution temperature. The crystalline nature of CdSSe-FFs is confirmed by high-resolution transmission electron microscopy (HRTEM) results, and selected area electron diffraction (SAED) observations reveal a hexagonal crystal structure. Additionally, the CdSSe-FFs thickness was confirmed by TEM analysis and found to be ~20-30 nm. The optical, photoelectric, and field emission (FE) characteristics are thoroughly explored which shows significant enhancement due to the formation of heterojunction between the gold-coated silicon substrate and CdSSe-FFs. The UV-visible absorption spectra of CdSSe-FFs show enhanced absorption at 700 nm, corresponding to the energy band gap (Eg) of 1.77 eV. The CdSSe-FFs exhibited field emission and photosensitive field emission (PSFE) characteristics. In FE study CdSSe-FFs shows an increase in current density of 387.2 µ A cm-2 in an applied field of 4.1 V m-1 which is 4.08 fold as compared to without light illumination (95.1 µ A cm-2). Furthermore, it shows excellent emission current stability at the preset value of 1.5 µA over 3 h with a deviation of the current density of less than 5% respectively. RESEARCH HIGHLIGHTS: Novel CdSSe flake flowers were grown on Au-coated Si substrate by a cost-effective chemical bath deposition route. The growth mechanism of CdSSe flake flowers is studied in detail. Field emission and Photoluminescence study of CdSSe flake flowers is characterized. CdSSe flake flowers with nanoflakes sharp edges exhibited enhanced field emission properties.

20.
Nanomaterials (Basel) ; 14(11)2024 May 25.
Article in English | MEDLINE | ID: mdl-38869555

ABSTRACT

The objective of this study is to create a planar solar light absorber that exhibits exceptional absorption characteristics spanning from visible light to infrared across an ultra-wide spectral range. The eight layered structures of the absorber, from top to bottom, consisted of Al2O3, Ti, Al2O3, Ti, Al2O3, Ni, Al2O3, and Al. The COMSOL Multiphysics® simulation software (version 6.0) was utilized to construct the absorber model and perform simulation analyses. The first significant finding of this study is that as compared to absorbers featuring seven-layered structures (excluding the top Al2O3 layer) or using TiO2 or SiO2 layers as substituted for Al2O3 layer, the presence of the top Al2O3 layer demonstrated superior anti-reflection properties. Another noteworthy finding was that the top Al2O3 layer provided better impedance matching compared to scenarios where it was absent or replaced with TiO2 or SiO2 layers, enhancing the absorber's overall efficiency. Consequently, across the ultra-wideband spectrum spanning 350 to 1970 nm, the average absorptivity reached an impressive 96.76%. One significant novelty of this study was the utilization of various top-layer materials to assess the absorption and reflection spectra, along with the optical-impedance-matching properties of the designed absorber. Another notable contribution was the successful implementation of evaporation techniques for depositing and manufacturing this optimized absorber. A further innovation involved the use of transmission electron microscopy to observe the thickness of each deposition layer. Subsequently, the simulated and calculated absorption spectra of solar energy across the AM1.5 spectrum for both the designed and fabricated absorbers were compared, demonstrating a match between the measured and simulated results.

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