Maximum Absorption Research Articles

Graphene-based hybrid metasurfaces with quasi-bound states in the continuum for manipulating terahertz absorption

We present a graphene-based hybrid metasurface with quasi-bound states in the continuum (BICs) for manipulating terahertz (THz) wave absorption. By the strategic application of structural perturbations for the THz metasurface, the symmetry-protected BICs transforms into quasi-BICs. The incorporation of graphene adeptly satisfies the critical coupling condition, thereby facilitating the attainment of the theoretical maximum absorption of 0.5 for the quasi-BICs in the THz region. And the Q-factor of the quasi-BIC can be up to 2755. Moreover, the metasurface exhibits a distinctive ability for unique tuning and efficient absorption of terahertz waves by varying the asymmetry parameter and Fermi levels. This work provides promising strategies for manipulating terahertz wave absorption.

Engineering of N doped carbon@FeCo alloy hollow spheres: Remarkable mid-frequency electromagnetic wave absorption performance exhibited by unique porous and wrinkled surface structure

The modulation of the shape and design of microstructures plays a crucial role in enhancing the efficient absorption of electromagnetic waves in absorbers. The electromagnetic parameters and scattering effects of these materials are directly influenced by their morphological characteristics. In this study, polystyrene microspheres were used as templates for a two-step in-situ growth process: Initially, Fe₃O₄ was coated onto the surfaces of these microspheres, followed by the in-situ growth of Fe-Co Prussian blue analogs. The rational design of electrical parameters during the conversion process was calculated and analyzed using Density Functional Theory. The precursor was calcined at various temperatures to generate a unique porous wrinkled surface hollow nanostructure. This nanostructure not only facilitates multiple reflections and scattering of incident electromagnetic waves but also promotes the occurrence of multiple interface polarizations. Doping with nitrogen and oxygen elements introduced abundant dipole polarization, thereby enhancing the electromagnetic wave attenuation capability of the composite material. The Fe3O4@PBA composite material synthesized at 600°C achieved a minimum reflection loss of −57.01 dB and a maximum effective absorption bandwidth of 4.58 GHz (7.52–12.1 GHz) at a thickness of 4 mm, covering nearly the entire X-band. This method provides a means to enhance magnetic loss by temperature adjustment to control the magnetic components in composite materials, providing a systematic approach to designing the microstructure of materials used for absorbing electromagnetic waves.

Highly Stable Binary Cross‐Linkable Organic Nonlinear Optical Materials Using Different Acceptors Based on Huisgen Cycloaddition Reaction

Comprehensive SummaryHow to obtain organic electro‐optic materials with large electro‐optic coefficients, high glass transition temperature, and good optical transparency remains a challenge in this field. To solve this problem, we introduce groups that can undergo Huisgen cycloaddition reactions into the donor and electron bridge of chromophores with large hyperpolarizability using tetrahydroquinoline as the donor. Binary cross‐linkable chromophores TLD1‐2 with CF3‐TCF as the acceptor and chromophores TLD3‐4 with 5Fph‐TCF as the acceptor were synthesized. After poling and crosslinking, the Tg of TLD1/TLD2 and TLD3/TLD4 were raised to 152 and 174 °C, respectively. The electro‐optical coefficients of chromophores TLD1/TLD2 and TLD3/TLD4 were as high as 312 pm/V and 287 pm/V, respectively. The long‐term alignment stability test showed that after being left at 85 °C for 500 h, the cross‐linked film TLD3/TLD4 can still maintain more than 98% of the original electro‐optical coefficient value, which is higher than that of TLD1/TLD2 (93%). The chromophore TLD3‐4 exhibited much blue‐shifted maximum absorption wavelengths (~40 nm) compared to TLD1‐2 which was beneficial for reducing optical loss in the device. The combination of high electro‐optic coefficient, strong stability, and excellent optical transparency makes the TLD series of binary cross‐linked materials very promising for practical high‐performance electro‐optic devices.

Circular-ring tied arc loaded excellent metamaterial absorber for EMI shielding of Wi-Fi signal and impurity sensing of cooking oil

This paper demonstrates a unique symmetric structure excellent metamaterial absorber (MMA) loaded with circular-ring tied arcs. The FR4 substrate-based MMA can accomplish 98.88 % and 99.81 % absorption maximums at the Wi-Fi and 5G frequencies of 2.4 GHz and 5.0 GHz respectively. The unit cell dimension of 0.16λ0×0.16λ0×0.0128λ0 is considered where the wavelength, λ0 is calculated at 2.4 GHz. The performance of the absorber is analyzed through the electric field, magnetic field, surface current, and effective parameters. The dimensions are optimized through the parametric analysis of the developed model in CST software. The model exhibits stability up to 60° for Transverse electric and magnetic polarizations. During electromagnetic interference (EMI) shielding demonstration, it can achieve a high shielding effectiveness (SE) of 54.34 dB at 2.4 GHz and 77.96 dB at 5.0 GHz. For sensing operation, it can attain a quality factor (Q-factor) of 25.61, a sensitivity of 3.30 %, and a figure of merit (FoM) of 84.51. The prototype measurements of the MMA for EMI shielding and impurity sensing of oil samples have a strong correlation with the simulation performance. Because of the high SE, Q-factor, sensitivity, and FoM, the developed MMA can be a competitive candidate in EMI shielding and oil impurity sensing applications.

Cu(β-diketonato)2 bathochromic shifts from the ultraviolet towards the visible region

ContextThe DFT-calculated ultraviolet/visible properties of 11 different Cu(β-diketonato)2 complexes are presented. The selected β-diketonato ligands on the Cu complex contain none, one or two aromatic rings. The experimentally measured absorbance maxima range of the ultraviolet/visible is observed at 295–390 nm, and the calculated range is 302–425 nm, for the 11 complexes in this study. More aromatic rings on the ligand lead to bathochromic shifts of the experimentally measured absorbance maxima from the ultraviolet towards the visible region. Absorbance maxima of the Cu(β-diketonato)2 complexes with no aromatic rings on the ligand are found to be predominantly ligand-to-metal charge transfer excitations, whereas introducing one or two aromatic rings shifts the excitations to predominantly ligand-to-ligand charge transfer.MethodsDFT calculations were conducted on the neutral molecules with multiplicity 2, using the PBEh1PBE functional and the aug-cc-pVDZ basis set as implemented in the Gaussian 16 package. The selected solvent was acetonitrile, the solvent in which most of the experimental UV/Vis are reported. The molecules were all optimized in the solvent phase, using the IEFPCM. The initial coordinates for the compounds were generated using Chemcraft.HighlightsTDDFT of 11 different Cu(β-diketonato)2 complexes follow the experimental trend.Aromatic rings on the ligand lead to Bathochromic shifts of UV/Visible spectra.No aromatic rings on the ligand lead to ligand-to-metal charge transfer excitations.Aromatic rings on the ligand lead to ligand-to-ligand charge transfer excitations.Graphical abstractBathochromic shifts in eco-friendly Cu(β-diketonato)2.

Investigating the Effects of Transition Metals and Activated Carbon on Hydrogenation Characteristics of Severely Deformed ZK60 Processed by High-Energy Ball Milling

The synergic effects of activated carbon and transition metals on the hydrogenation characteristics of commercial ZK60 magnesium alloy were investigated. Severe plastic deformation was performed using equal-channel angular pressing with an internal die angle of 120° and preheating at 300 °C. The ZK60 alloy samples were processed for 12 passes using route BA. The deformed ZK60 alloy powder was blended with activated carbon and different concentrations of transition metals (Ag, Pd, Co, Ti, V, Ti) using high-energy ball milling for 20 h at a speed of 1725 rpm. The amount of hydrogen absorbed and its kinetics were calculated using Sievert’s apparatus at the higher number of cycles at a 300 °C ab/desorption temperature. The microstructure of the powder was analyzed using an X-ray diffractometer and scanning electron microscope. The results indicated that 5 wt% activated carbon presented the maximum hydrogen absorption capacity of 6.2 wt%. The optimal hydrogen absorption capacities were 7.1 wt%, 6.8 wt%, 6.7 wt%, 6.64 wt%, 6.65 wt%, and 7.06 wt% for 0.5 Ag, 0.3 Co, 0.1 Al, 0.5 Pd, 2 Ti, and 0.5 V, respectively. The hydrogen absorption capacities were reduced by 35.21%, 26.47%, 41.79%, 21.68%, 26.31%, and 26.34% after 100 cycles for 5C0.5Ag, 5C0.3Co, 5C0.1Al, 5C0.5Pd, 2Ti, and 5C0.5V, respectively. Hydrogen absorption kinetics were significantly improved so that more than 90% of hydrogen was absorbed within five minutes.

Synergistic charge-transfer dynamics of novel D-D-A-π-A framework containing indoline-benzo[d][1,2,3]thiadiazole based push-pull sensitizers: from structural engineering to performance metrics in photovoltaic solar cells.

Dye-sensitized solar cells (DSSCs) present a convincing substitute for conventional silicon-based solar cells because of their possible lower manufacturing costs and versatile uses. Electron injection and dye regeneration processes are important in meeting the need for photosensitizers with improved efficiency and stability. Aimed at enhancing the performance and efficiency of DSSCs, this study focuses on the structural engineering to performance metrics of novel indoline-benzo[d][1,2,3]thiadiazole based push-pull sensitizers (LHZ1 to LHZ9) with D-D-A-π-A framework. The current study provides insights into the photovoltaic and optoelectronic properties of the investigated dyes, which are significantly influenced by the modification of auxiliary donors (D), internal acceptors with thiophene as a spacer, and cyanoacrylic acid (A) as the terminal acceptor. These modifications enhance rapid charge transfer among the dyes, highlighting the critical role of dye-semiconductor interactions. The suitability of developed sensitizers for DSSCs applications is confirmed by executing quantum methods like NBO, TDM, FMO, DOS, Eb, ΔGreg, ΔGinject, VRP, and ICT parameters qCT (e-), DCT ( ), H index ( ), ∆( ), t index ( ), and μCT (D). All of the investigated dyes have HOMO levels lower than the electrode I-/I3-'s redox potential (-4.8 eV) and LUMO values that are appropriately higher than the conduction band of TiO2 (-4.0 eV). The novel dyes showed a closing of the energy gap (2.38-1.84 eV). The LHZ7 and LHZ8 molecules with the lowest Eg (1.97 eV and 1.84 eV) demonstrated the highest absorption (up to 746 nm > 402 nm for LHZ), which was caused by the insertion effect of varied donors and internal acceptors. Almost all photosensitizers appeared with remarkable properties, i.e., red-shifted absorption maxima (746 nm), lowest Ex (1.66 eV), Eb (0.02 eV), and highest values of LHE (0.958). The TDM analysis revealed high charge density on HOMO of donor and LUMO of acceptors in designed dyes. DOS analysis revealed that the donor parts of the molecules delocalized the highest occupied molecular orbitals of dye particles. The electronic properties predicted by the NBO analysis showed that donor groups donate high and faster transfer of charge, and internal acceptor groups rapidly accept them. The electron injection (ΔGinject) and dye regeneration (ΔGreg) analysis of photosensitizers attached with TiO2 proved efficient charge transfer properties from the donor of newly designed dyes onto the conduction band of TiO2. This study, also supported by the thermodynamic stability of dyes with negative values of Gibbs free energy, revealed that the performance of the designed dyes is augmented by modifying the donor and internal acceptors of the reference photosensitizer for effective application in the experimental community. All of the dyes are suitable for DSSCs based on the calculated parameters. Still, the LHZ9 dye proved proficient in applying dye-sensitized solar cells due to its remarkable properties, i.e., lowest gap and red-shifted absorption maxima.

Comparative investigation of structural, electronic, mechanical and optical responses of CsPbI3-PbSe and CsPbI3 with Mg-doped for optoelectronic applications: A first-principles study

A and B-site doping has been viewed as a very effective approach to stabilise the desired perovskite cube phase of pure and doped hetero-structure CsPbI3-Pb1-xMgxSe and the simple system CsPb1-xMgxI3. In this analysis, the effect of (Mg2+) on the crystal structure, electronic, mechanical, and optical responses of hetero-structure CsPbI3-Pb1-xMgxSe and CsPb1-xMgxI3 were thoroughly investigated, by employing first-principles computations. A theoretical study of target responses of the metal-halide CsPbI3 is presented with a plane wave ultra-soft pseudopotential approach as personified in the CASTP code. The computed results show that the band gap of CsPbI3-Pb1-xMgxSe can be changed from '1.809eV' to '1.75eV' when the concentration range (x = 0 to 0.25) is changed. A valuable band gap of '0.48eV' and '1.28eV' of doped CsPbI3-Pb1-xMgxSe can be achieved under concentrations changed from (x = 0.25 to '0.75eV') and as shown in direct (Γ - Γ) nature and become optically active. The density of states shows that Cs-6p, I-4p, and Pb-6p states contribute to the valence band maximum, whereas the main involvement conduction band minimum by Mg-5p and Cs-6p states in the CsPbI3-Pb1-xMgxSe system. Elastic properties designate the flexibility and softness of target materials. The computed elastic parameters further indicate that this hetero-structure material is stable under the doping concentration condition. Replacing the Pb2+ site with Mg2+ has red-shifted the maximum absorption edges and changed the optical characteristics to be anisotropic. Their ability of these two materials with their Mg2+ based mixed halide perovskite nature for optoelectronic applications.

28 Integrating homeostasis in practical mineral supplementation recommendations

Abstract A long-established objective in ruminant nutrition is an accurate supply of the 4 main trace metal nutrients Zn, Cu, Mn, and Fe, respecting bioavailability, nutritional interactions, and nutrient tolerance. Although, current dietary supplementation practices, justified by the multiple uncertainties of trace metal supply, results in dietary levels that widely exceed nutritional guidelines. Additionally, reference feeding recommendations are defined assuming fixed and highly conservative uptake coefficients, an approach that disregards the opportunity, and limitations, of absorptive regulation, the main homeostatic mechanism of these nutrients. Mitigating deficiency risks by generous supplementation can result in a generally overlooked risk, exceeding tolerable trace metal availability. Complete nutrient balance studies have recently described the overwhelming homeostatic downregulation of trace metals at dietary levels that are not uncommon in practice. This finding calls for a novel approach to define supplementation that resolves this conundrum of trace metal adequacy. This approach integrated 3 elements: a stochastic analysis of native dietary supply; a stochastic analysis of net nutrient requirements; and the identification of the upper and lower boundaries of homeostatic regulation for these 4 nutrients in the bovine species. This last, aims to resolve the main limitation of current dietary guidelines, using the potential maximum uptake rates in homeostatic upregulation, and the minimum uptake rates achievable by downregulation, instead of assuming fixed uptake rates. As result, this approach delivers dietary supply ranges of adequate supply, instead of a minimum dietary level to meet dietary adequacy. The probability distribution of nutrient supply was determined by dry-matter intake variability, diversity in dietary composition, and variability of nutrient occurrence in feedstuffs. The probability distribution of net nutrient requirements was defined by the variability of the components of a classic factorial requirement approach applied to different animal conditions. A maximum apparent absorption efficiency was determined to define lower supply boundaries using published datasets. Upper boundaries were defined as the dietary supply level beyond which apparent absorption empirically has shown to exceed net requirements. As expected, this risk-based approach resulted in much lower supplementation recommendations than current reference models. However, it supports the value of preventive supplementation of Zn and Cu to growing and lactating animals, and Cu to non-lactating non-growing cows. This assessment also indicates merit in Mn supplementation to growing bovines. Furthermore, it confirms that under all circumstances native dietary Fe meets nutritional needs, but it also illustrates a tolerance risk to native Fe supply under multiple productive scenarios. Most interestingly, this analysis illustrates the risk of exceeding trace metal tolerance boundaries with common levels of supplementation under common conditions. This approach offers a novel perspective to trace metal supplementation, pointing at an opportunity to improve nutritional adequacy by reconsidering supplementation practices.

Explored the potential of Rb2SeX6 (X=Cl, Br) double perovskites for energy harvesting devices: A DFT study

In this study, we employed Density Functional Theory (DFT) to comprehensively analyze the structural, mechanical, electronic, optical, and transport characteristics of Rb2SeX6 (X=Cl, Br) double perovskite halides. Our investigation aimed to assess the stability and suitability of these materials for energy harvesting devices. To evaluate material stability, we performed optimization and mechanical calculations. The computed bulk modulus indicated that the Rb2SeX6 (X=Cl, Br) compounds possess mechanical stability. Nevertheless, both compounds satisfied stability requirements for cubic structures, ensuring their potential utility. Using the modified Beck-Johnson approximation, we determined the indirect electronic band gaps to be within the range of 2.15 eV to 2.61 eV. These values indicate that the indirect band gaps of Rb2SeX6 (X=Cl, Br) compounds fall within the visible region due to the strong orbital coupling of the cations. Notably, the conduction band minimum mainly consists of Se-4p elements, while the valence band maximum predominantly comprises X-3p elements. Furthermore, the replacement of halogen atoms significantly influences the optical characteristics of the double perovskites. We observed that the complex dielectric function advocates the maximum electron transition and absorption efficiency when photon energy (eV) subjected on the Rb2SeX6 (X=Cl, Br) compounds. Further, considered the transport properties against temperature, chemical potential, and carriers’ concentrations. These findings emphasize the potential of Rb2SeX6 (X=Cl, Br) compounds double perovskites for energy harvesting applications. In conclusion, our study highlights the favorable properties and stability of Rb2SeX6 (X=Cl, Br) double perovskites, as revealed through DFT analysis. These materials exhibit desirable electronic and optical characteristics, making them promising candidates for energy harvesting devices.

Preparation, characterisation, physical, and compression testing of sucrose based closed-cell aluminium foam

ABSTRACT Aluminium foam can be used as a porous and lightweight material having comparatively high impact energy absorption. To reduce the death rate caused by collisions of vehicles, there is a need of analysing the crash-worthiness properties of materials. In this present work, the Aluminium foam was prepared using the powder metallurgy method for the crash-worthiness analysis. The Al6061 powder as a matrix material having particle sizes ranging from 5 to 30 µm and Sucrose particles as a space-holding material were mixed. The compaction process was done up to a pressure of 450 MPa to make the green compact and was further subjected to sintering up to a temperature of 500 °C for 1 hour resulting into the Aluminium foam. The compressive strength significantly decreased by 26.56%, 51.39%, 72.49%, and 64.34% approximately while volume fractions of sucrose particles varied as 20%, 30%, 40%, and 50%. On the other hand, the measured maximum porosity was found as 51.8% approximately in the Aluminium foam corresponding to the addition of 50% sucrose particles by volume. Out of all the examined samples, the foam developed by containing 20% (vol.) sucrose has exhibited the maximum strain energy absorption, specific energy absorption (SEA), and crushing force efficiency (CFE).

Fabrication of Famotidine Loaded Sepiolite/Pectin Bionanocomposite Hydrogels for Controlled Drug Delivery

AbstractDevelopment of drug delivery systems is an extensively researched area in the biomedical field. In recent years, there has been an increasing interest in fabrication of biocompatible nanofibrous drug delivery systems. The present study describes the fabrication of calcium chloride‐crosslinked bionanocomposite hydrogels based on pectin for the use of gastro‐retentive delivery system. Sepiolite/famotidine/pectin nanocomposite hydrogel was fabricated by using Ionotropic gelation process. The thermal, structural and morphological properties were evaluated via different experimental techniques such as TGA‐DSC, FTIR, and SEM. The prepared hydrogels showed a pH sensitive swelling profile with maximum water absorption at pH 1.2. Analysis of in‐vitro drug release data revealed that the sepiolite/famotidine/pectin nanocomposite hydrogels exhibited a slight initial burst release, followed by a sustained release over a 24 h period. This was observed both in simulated gastric fluid and in phosphate‐buffered saline, suggesting that these hydrogels are well‐suited for prolonged drug delivery. To investigate the drug release kinetics, various models were applied. The release of famotidine was predominantly governed by diffusion, as described by the Korsmeyer‐Peppas model.

A first principles based exploration of Rb2XHgCl6 (X= Al, Y) halide double perovskites for their applications in futuristic efficient technologies

Herein, the first principles calculations are performed to explore the physical features of Rb2XHgCl6 (X = Al, Y) to unravel their potential candidacy for optoelectronic and thermoelectric applications. The geometry optimization reveals that Rb2XHgCl6 (X = Al, Y) are stable in cubic structure with ferromagnetic nature. Analysis of tolerance factor and formation energies uncovered the thermodynamically stability. Moreover, the semiconductor nature of considered compounds is confirmed by spin dependent electronic characteristics. Rb2XHgCl6 (X = Al, Y) revealed maximum absorption of ultraviolet light which prove that corresponding materials are appropriate for optoelectronic devices. Using BoltzTraP package, the thermoelectric (TE) characteristics are computed within range of 100–800 K. Results suggest that the resultant material are appropriate candidates for spintronic, optoelectronic and TE applications and more stimulate experimentalist to discover these materials for their usage in practical extent.

Unfavorably altered fibrin clot phenotype in women following postpartum hemorrhage of unknown cause: effect of lower coagulation factors.

Background Increased clot permeability and susceptibility to lysis have been reported in women with heavy menstrual bleeding. We hypothesized that similarly altered fibrin clot properties in women with postpartum hemorrhage (PPH) of unknown cause. Objective To determine fibrin clot properties and their determinants in women after PPH of unknown cause. Methods We studied 52 consecutive women, aged 35 years (27-40), after at least 3 months since PPH of unknown cause and 52 matched controls for age, weight, and fibrinogen. Coagulation factors (F), antithrombin, thrombin generation, along with a comprehensive plasma fibrin clot analysis including fibrin polymerization, clot permeability (Ks), and fibrinolysis efficiency were determined. Results Women with PPH showed reduced activity of FII (-10.3%), FV (-6.6%), FIX (-6.5%), FX (-7.2%), and FXI (-5.7%) compared to the controls, though all values were within ranges (all p<0.05). There were no intergroup differences in fibrinogen, FVIII, FXIII, and thrombin generation. The PPH group formed with a delay looser plasma fibrin network (Ks; +16.3%, p=0.008) with lower maximum absorbance and shorter clot lysis time (CLT; -13.5%, p=0.001) compared to the controls. On multivariable logistic regression, PPH was independently associated with higher C-reactive protein (per 1 mg/L, OR=1.70, 95% CI 1.09-2.68), lower FII (per 1%, OR=0.93, 95% CI 0.89-0.98), lower FV (per 1%, OR=0.93, 95% CI 0.89-0.97), and shorter CLT (per 1 min, OR=0.94, 95% CI 0.90-0.98). Conclusion Prohemorrhagic fibrin clot properties, with lower, though normal coagulation factors characterize women with PPH of unknown cause, which suggests novel mechanisms contributing to this type of bleeding.

Saponin-mediated and microwave-assisted biosynthesis of silver nanoparticles: preparations and anticancer assessment

Silver nanoparticles have been extensively studied and used for biological and biomedical applications due to its antimicrobial properties. In this study, we have developed silver nanoparticles with saponin (S-AgNPs) using microwave-mediated methodology and physiochemically characterised and evaluated its anticancer potential. According to UV–visible spectroscopy, S-AgNPs exhibited a maximum absorption peak at a wavelength of 420 nm. DLS analysis revealed that S-AgNPs have an average diameter of around 133.8 ± 10 nm. HR-TEM analysis confirms the spherical morphology of S-AgNPs. Further, the anticancer effect of S-AgNPs was validated using A459 lung cancer cells by in vitro cell interaction tests such as the MTT assay, staining assay, and flow cytometry assay. The IC50 value of S-AgNPs against A549 cells was 30 μg ml−1, and Calcein-EtBr and Annexin V/PI staining results confirm the presence of apoptotic cells after treatment S-AgNPs. Hence, biosynthesized S-AgNPs can play a vital role in developing anticancer drugs for cancer treatment.

Synthesis and characterisation of visible light-responsive Fe-doped BiOCl NPs and their application for the remediation of textile dye by LED irradiation

ABSTRACT In the present research work, Fe-doped bismuth oxychloride (Fe-doped BiOCl) photocatalyst is synthesised through the precipitation technique, and the mineralisation of textile dye is investigated in the presence of light-emitting diode (LEDs) irradiation (400–700 nm). The prepared photocatalysts were characterised through various spectroscopic techniques for the detailed morphological, elemental and surface properties. The UV–vis absorbance maxima of Fe-doped BiOCl by UV-Vis was near 358 nm, while the band gap was 4.8 eV which is comparatively higher than the average value. Fourier transform infrared spectra showed typical bands of Fe doped BiOCl at 506 cm−1, 1601, 2337 and at 3565.0 cm−1. From the X-ray diffraction (XRD) pattern, the crystalline nature of the Fe-doped nanocomposite was confirmed whose calculated crystallite size was 41.12 nm. The major and sharp two theta peaks of XRD were at 11.95°, 24.07°, 25.81°, 32.46°, 33.39°, 36.47°. The microscopic technique showed that the size of the nanocomposite was 200–400 nm which was in the form of small nanosheets. The energy dispersive X-ray spectroscopy (EDS) showed peaks for Bi, O, Cl and Fe 36.91%, 26.48%, 36.37% and 0.24%, respectively, indicating the formation of the nanocomposite. The BET surface area of the Fe-doped BiOCl photocatalyst was 10.224 m2/g, while the pore volume was 0.065 cc/g. Further, the potential of the developed photocatalytic nanocomposite was evaluated for the photocatalytic degradation of the ethyl violet dye from the aqueous solutions. Various optimisation parameters have been discussed, and it has been found that 89% of the dye was degraded in 125 min with a 5.11 × 10−4 s−1 rate constant. The photocatalyst had shown excellent reusability and stability during the degradation of ethyl violet. The photocatalytic activity of Fe-doped BiOCl was compared with other photocatalysts and current literature and exhibited enhanced efficiency.

Intramolecular hydrogen bonding steered optical recognition of fluoride ion and consequent opto-chemical logic responses: Spectroscopic and computational studies

This work demonstrates the synthesis and characterization of a thiosemicarbazide core containing Schiff base molecule (MNHC) and its use as a chemosensor for the selective, ratiometric, and colorimetric detection of fluoride ions. The study reveals that in the presence of F− ions, MNHC displays a ratiometric change of absorption maxima at two different wavelengths (432 and 330 nm). MNHC involves an intramolecular hydrogen bonding initiating the possibility of keto-enol tautomerism which is thoroughly investigated by DFT study. Interestingly, the intramolecular hydrogen bonding enhances the acidity of the –NH proton and consequently the –NH center becomes more labile for F− ions binding over the other –NH proton. This fact is confirmed by 1H NMR study. Remarkably, F− ion forms intermolecular hydrogen bonding with the –NH moiety disrupting the intramolecular hydrogen bonding. The changes in absorption spectra in the presence of F− ions occur due to the intermolecular hydrogen bonding-assisted abstraction of the –NH proton. On the other hand, when H2O is added to the MNHC-F− composite, the spectroscopic signature of free MNHC is completely regenerated due to the transfer of proton from H2O to the nitrogen center of MNHC. In addition, 1:1 binding stoichiometry and 53.7 μM detection limit for fluoride ion are also confirmed. Moreover, utilizing these spectroscopic responses, different kinds of important opto-chemical logic gates like YES, NOT, PASS 0, PASS 1, INHIBIT, TRANSFER, and IMPLICATION are developed. Moreover, the F− ion-assisted competitive nature between the intramolecular vs intermolecular hydrogen bonding is thoroughly explored by substantial DFT study.

Optimal extraction, phytochemical and electrochemical potential assessment of pigments from Persicaria Lapathifolia for dye-sensitized solar cell application

In this study, we concentrated on optimal extraction, phytochemical, and electrochemical assessment of natural pigments from the roots and flowers of Persicaria lapathifolia as new sensitizers in dye-sensitized solar cells. The extraction technique required optimizing the use of acidified ethanol with acetic acid and hydrochloric acid as flower and root extractants, respectively. Photo-electrochemical tests revealed that these pigments could improve the efficiency of DSSCS. The optical characterization revealed maximal absorbance peaks at 462 and 654 nm for root dye and 535, 606 and 666 nm for blossom dye. Phytochemical examination revealed the presence of anthocyanins flavonoids glycoside linkage and betacyanin in both extracts. The Cyclic voltammetry tests revealed oxidation potential peaks in root and floral dyes the HOMO and LUMO potentials were calculated for both dyes, revealing values that could help improve DSSC performance. The DSSCS sensitized with flower extract had an open circuit voltage of 0.649 V a brief current pulse of 3.8 mA and an efficiency of 1.6335%. On the other hand root, pigment-based DSSCS performed slightly inferior with a Voc of 0.55 V an Isc of 3.7 mA, and an efficiency of 1.33%. These findings point to the potential of Persicaria lapathifolia pigments to boost DSSC efficiency emphasizing the relevance of sustainable energy sources. More research and optimization are required to realize the potential of these natural pigments for DSSC applications. This study adds to the investigation of green energy options, notably rooftop photovoltaic systems, in response to an increasing desire for ecologically sound energy solutions.

Exploring Broadband Electromagnetic Absorption Characteristics and Composition Optimization in Novel Synthesized Ni2Fe1+xGe1−x Alloy Powders

This study reports for the first time the successful synthesis of a novel series of Ni2Fe1+xGe1−x (x = 0.25, 0.50, 0.75, 0.90) polycrystalline alloy materials with L21 austenite structure using the mechanical alloying method. Notably, the Ni2Fe1+xGe1−x alloys demonstrate excellent electromagnetic wave absorption performance across the entire 2–18 GHz frequency range, and by adjusting the composition ratio of iron and germanium, it is possible to effectively regulate their complex permittivity () and permeability (), thereby adjusting the reflection loss. All Ni2Fe1+xGe1−x samples show an effective electromagnetic wave absorption effect of more than −10 dB, indicating that 90% of the electromagnetic waves are efficiently absorbed. Among them, the Ni2Fe1.5Ge0.5 sample achieves an outstanding −43.5 dB reflection loss at 3.2 GHz, and the maximum effective absorption bandwidth reaches 5.8 GHz (11.8–17.6 GHz) with just a 1.6 mm thickness, fully covering the Ku band. This excellent absorption ability comes from the strong ability of the material to reduce signal strength and its perfect impedance matching. This study first shows the high potential of Ni2Fe1+xGe1−x ferromagnetic alloys as effective, wide‐range electromagnetic wave absorbers. It suggests the ferromagnetic Ni2Fe1+xGe1−x alloys hold promise as appealing candidates for broadband and high‐efficiency electromagnetic wave absorption.

Impact of halogens modifications on physical characteristics of lead-free hybrid double perovskites compounds Cs2YCuX6 (X=Cl, Br, and I) for energy storage applications: First principles investigations

The purpose of this study is to examine the structural, electronic, optical, and thermoelectric features of novel double perovskite Cs2YCuX6 (X=Cl, Br, and I) for the first time in order to look for potential applications in solar power systems. Using first-principles calculations based on the widely recognized Density Functional Theory (DFT) and the PBE-Generalized Gradient Approximation (GGA) functional included in the WEIN2k package, the characteristics of the perovskites were determined. From the results of band structure and Total Density of States (TDOS) the energy band gap of Cs2YCuCl6, Cs2YCuBr6, and Cs2YCuI6 are observed 2.34 eV, 2.03 eV and 1.68 eV respectively. The PDOS outcomes shows that the formation of the valance and conduction bands is due to the hybridization of Cu-3d and halogen ions such that (X=Cl, Br, and I). The calculated values of goldsmith’s tolerance factor and formation energy reveal that the examined halide perovskites are structurally and thermodynamically stable. The electron localization function ELF and bader charge analysis show that the ionic nature between Cs and halogen ions X. Regarding the optical behavior, Cs2YCuI6has shown maximum absorption of electromagnetic radiation and conductivity in the ultraviolet and visible region i.e. (128–471 nm) which makes it a suitable candidate for optoelectronic and solar cell applications. The thermoelectric properties of the studied compounds have been calculated by means of the Boltztrap code. The presented findings unveil that amongst all studied compoundsCs2YCuI6 is best candidate for solar cell and thermoelectric applications due to higher conductivity, larger absorption range, significant Seebeck coefficient and higher Power factor.