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• Two Fe3+ fluorescent probes based D-A type imidazole derivatives have been developed, which possessed a relatively great selectivity and sensitivity. • The probe molecules showed a relatively rare fluorescence color change response to Fe3+, its fluorescence changed from deep-blue to green. • The fluorescence sensing behavior of the probe molecules to Fe3+ was also applied to realize the rewritable paper in a very simple way. D-A type fluorescent probe usually shows a fluorescence quenching response to Fe3+, and relatively few probes can exhibit the fluorescence color change response. Herein, two high-luminescence D-A type imidazole derivatives TPABM and TPAFM were synthesized and used as Fe3+ fluorescent probes with an obvious fluorescence color change and remarkable sensing performance. Upon the addition of Fe3+, the original emission of TPABM and TPAFM was quenched, while a new emission peak emerged in the red-shifted direction, resulting in the fluorescence color changing from deep blue to green. This phenomenon may be caused by the coordination between the molecular imidazole ring and Fe3+ with a 1:1 ratio, which efficiently decreased the LUMO energy level of the probe molecules and formed a new CT emission with a lower energy gap. Furthermore, the probe molecules exhibited the potential for detecting Fe3+ in actual water samples and could be appropriated for the preparation of rewritable paper using a simple method. By using filter paper soaked with probe molecules as writing paper, Fe3+ aqueous solution as ink, and NaF aqueous solution as an eraser, the cycle of fluorescence writing and erasing was realized under UV irradiation. [Display omitted] [ABSTRACT FROM AUTHOR]

We herein demonstrate polypyrrole decorated micro-porous laboratory filter paper (PFP) as photoanode (PA) for efficient and stable water splitting. The straddling band position with water redox and the measured band gap of ~1.98 eV, make these PFP-PAs effective for water splitting reactions. The results manifest excellent photo-anodic PEC activity of these PFP-PAs, yielding a photocurrent density of ~9.5 mA/cm2 (at 1.23 V vs. RHE) in a three-electrode configuration. The incident photon-to-current efficiency (IPCE) and applied bias photon-to-current efficiency (ABPE) was measured to be 43.19% and ~1%, respectively. Moreover, the robustness of these flexible PFP-PAs was visualized by the provided stability for more than ~160 min in alkaline conditions. The current study provides a proof-of-concept for the realization of a cost-effective, flexible, and efficient paper-based artificial catalyst (like a natural leaf) for solar-driven water splitting. Image 1 • In-situ fabricated polypyrrole based flexible filter paper photo electrode (PFP-PEs). • Exhibit a bandgap of ~1.98 eV and reported as PEs for water splitting. • Photocurrent density of ~9.5 mA/cm2 (at 1.23 V vs. RHE) in 3-electrode system. • IPCE and ABPE was measured to be 43.19% and ~1%, respectively. • PFP-PEs stable for 160 min in alkaline conditions for PEC water splitting. [ABSTRACT FROM AUTHOR]

The use of microfluidic fuel cells (μFCs) as power sources in the development of non-implantable biomedical devices, such as patch sensors, could be broadened with the use of physiological fluids as fuels and the use of low-cost materials. In this work, we report the evaluation of a paper-based photo-μFC working with human blood as fuel, and we implement a nanocomposite as anode that presents photoactivity under visible light. The electrocatalyst was synthesized using Zn(NO3)2 and TiCl4 as precursors of the ZnO and the TiO2, respectively, which were coated with Au nanoparticles. It was demonstrated that ZnO and TiO2 nanoparticles consisted of crystals with wurtzite and anatase phases, with average sizes of 26.6 and 19.5 nm, respectively, and the TiO2/ZnO/Au nanocomposite presents 2.62 eV of band gap energy, demonstrating its photoactivity under visible light irradiation. The photocatalyst was tested as photoanode in half-cell for glucose oxidation in aqueous solutions, under illumination and dark conditions, showing characteristics peaks of glucose oxidation in both cases, but higher current was generated under illumination. Finally, we present the implementation of this anode and the construction of a paper-based photo-μFC using human blood as fuel; its performance was evaluated under visible light irradiations and in the dark. The results show a better performance under illumination with voltage, current, and power density values of 0.95 V, 1.2 mA cm−2, and 0.458 mW/cm2, respectively, compared to the corresponding values of 0.8 V, 0.96 mA cm−2, and 0.274 mW/cm2 in dark conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile and scalable self-assembly of perylene diimide polymer with carbon paper. • Effective facilitation of carrier separation by π-π built-in electric field. • Narrowed band gap and low VB due to the VB tail states induced by π-π interactions. • Enhanced photocatalytic water oxidation activity of the PDIP/CP photocatalyst sheet. • Suitability of the PDIP/CP photocatalyst sheet for large-scale applications. Photocatalytic water splitting is a highly promising future energy technology. In contrast to the extensive work on particulate photocatalysts, there is still a lack of sufficient investigation for regularized photocatalysts. Here, from perylene diimide polymer (PDIP) and commercial carbon paper (CP), we develop a self-assembled PDIP/CP photocatalyst sheet that is easily scalable and can be used for photocatalytic water oxidation. Driven by strong interfacial π-π interactions, the PDIP spontaneously adsorbs onto the CP, which leads to a narrowed band gap, down-shifted VB edge, and enhanced separation of the photogenerated charge carriers of the PDIP. Under visible light, the PDIP/CP photocatalyst sheet shows significantly enhanced photocatalytic water oxidation activity (4 h cumulative oxygen evolution is 1.7 times higher than that of the powder-suspended system) and considerable cycling stability. The PDIP/CP photocatalyst sheet has the potential for large-scale device applications. [ABSTRACT FROM AUTHOR]

In the current research work "4-{[1-(2,5-dihydroxyphenyl)ethylidene]amino}-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one" chemosensor (C1) synthesized by condensation reaction using "4-amino-1,2-dihydro-1,5-dimethyl-2-phenylpyrazol-3-one" and "2,5-dihydroxy actophenone" was used as the effective sensor of metal ion. The C1 shows absorption peak at 326 nm due to the C = C bond (π-π* transition), while the absorption peak at 364 nm is caused by the C = O bond (n-π* transition). In the presence of copper, C1 only demonstrated a redshift in absorption peak from 364 to 425 nm. Even in the presence of other competing metal ions, the hypsochromic shift of the absorption band and the quenching of the fluorescence emission intensity were different for detecting Cu2+, in CH3OH-H2O (v/v = 6:4). The capacity of the C1 to bind with Cu2+ was further proved using DFT simulations. The complex C1 + Cu2+ has a HOMO–LUMO energy gap of 2.8002 eV, which is lesser than C1 (2.9991 eV) showing improvement in the stability of the C1 + Cu2+ complex. Using the Benesi-Hildebrand and Scatchard plots, calculated Kb values were to be 47,340 and 48369 M−1 respectively, showing the creation of stable complexation between Cu2+ and C1 with 1:1 stoichiometry. The limit of detection (LOD) for Cu2+ ion was 649 nM. Strip sheets were also built and tested to detect varying amounts of Cu2+ in aqueous solution, and their color change suggested that they might be used for on-site Cu2+ detection in polluted water. [ABSTRACT FROM AUTHOR]

Microfluidic paper-based analytical devices modified with molecularly imprinted polymers (μPADs@MIPs) were developed for fluorescent detection of targeted thiols via in situ UV-induced formation of quantum dots (μPADs@MIPs@QDs). The selectivity enhancement by the MIP layer formed on the filter paper surface was demonstrated for the isolation of L-homocysteine from wine. Followed by the addition of metal precursors solution (Zn/Cd/Cu) and UV irradiation, fluorescent quantum dots were formed thus enabling quantitative detection of the thiol (serving as a QD capping agent). The effect of different semiconductors was investigated to achieve a lower band gap and higher fluorescence intensity. Increasing fluorescence intensity in the presence of thiol groups was obtained for the following precursors mixture composition: ZnCdCu/S > ZnCd/S > ZnCu/S > ZnS. The proposed method has a good relationship between the fluorescence intensity of ZnCdCu/S QDs and L-homocysteine in a linear range from 0.74 to 7.40 μM with a limit of detection (LOD) and quantification (LOQ) of 0.51 and 1.71 μM respectively. This method was applied for the determination of L-homocysteine in white wine with RSD under 6.37%. [Display omitted] • Microfluidic paper-based analytical devices modified with MIPs (μPADs@MIPs). • Selective isolation of L-homocysteine from wine. • UV- induced in situ formation of fluorescent clusters. [ABSTRACT FROM AUTHOR]

This work presents machine learning (ML) assisted Fermi level prediction of solution‐processed ultra‐wide bandgap (UWB) amorphous gallium oxide (a‐Ga2Ox) which can significantly accelerate the fabrication of semiconducting UWB a‐Ga2Ox‐based material for future display application. Different models such as Kernel Ridge Regression (KRR), Support Vector Regression (SVR) and Random Forest Regression (RFR) were trained with empirical features, including experimental thickness, annealing temperature and environment during the solution‐processed UWB a‐Ga2Ox film fabrication. This work is a big step towards rapid and cost‐effective optimization method of fabricating UWB a‐Ga2Ox‐based devices. [ABSTRACT FROM AUTHOR]

In this study, we reported the photoluminescence (PL) behaviour of a new intramolecular charge transfer (ICT) compound, ((E)-2-(((2-hydroxynaphthalen-1-yl)methylene)amino)benzoic acid, (HABA), which shows ICT solvent effect in aprotic solvents as confirmed by absorption and emission spectra. While in protic solvents including water and ethanol, the charge transfer (CT) band significantly reduces. Remarkable fluorescence enhancement in the blue region was also observed for HABA in polar protic solvents. We described such phenomena as “specific solvent effect”. It can be ascribed to the hydrogen bonding formation between HABA and protic solvents, which not only causes significant reduction in the rate of internal conversion but also elevates the energy gap. Density functional theory (DFT) calculations as well as the dynamics analysis were performed to further verify the existence of hydrogen bonding complexes. Stronger emission turn-on effect was observed on HABA solid film when it is treated with water and base solution. The stimuli-responsive fluorescence of HABA enables a new green printing technique that uses water/base as the ink, affording fluorescent handwritings highly distinct from the background. Thermoanalysis of the dye suggests the nice thermostability, which is highly desired for real-world printing in a wide temperature range. [ABSTRACT FROM AUTHOR]

Abstract This comment concerns the doubtful new auxiliary equation method (Khater method) included in the above paper. We prove by simple calculation that this method is wrong. The exact solutions of the proposed nonlinear equation obtained in the above paper are all wrong. Highlights • The new auxiliary equation method is called Khater method. • We prove by simple calculation that Khater method is wrong. • We show that the exact solutions obtained in the above paper are all wrong. [ABSTRACT FROM AUTHOR]

A novel colorimetric-fluorescent dual-mode sensing sensor JT5 was successfully synthesized, and exhibited red fluorescence enhancement effect and red colorimetric sensing, and excellent applicability through solid-state fluorescent strips and biological imaging experiments on zebrafish to highly sensitive monitoring Sn4+ ions. [Display omitted] • A novel and effective rhdamine B-based sensor JT5 successful development. • JT5 can serve as a fluorescent and colorimetric on-off sensor for Sn4+. • The sensor JT5 was successfully studied using fluorescence and colorimetric of the test strips. • Biomaging experiments for the sensor JT5 were conducted on zebrafish using a confocal microscope. A novel colorimetric-fluorescent dual-mode chemosensor (JT5) based on rhodamine B has been produced for monitoring Sn4+ in the DMSO/H 2 O (4:1, v/v) medium. It has high sensitivity, a low detection limit, a short response time (1 s) and high stability, and can still be maintained after two weeks with the red dual fluorescence/ colorimetric response. Enhancement of red fluorescence (591 nm) and red colorimetric (567 nm) response of JT5 by Sn4+ addition. The electrostatic potential of the sensor JT5 molecule was simulated to speculate on the sensing mechanism, and the IR, mass spectrometry and 1H NMR titration were utilized to further demonstrate that JT5 was coordinated to Sn4+ with a 1:1 type, the rhodamine spironolactam ring of JT5 opens up to form a penta-membered ring with Sn4+, meanwhile, its system may have chelation enhanced fluorescence (CHEF) effect. In addition, theoretical calculations were carried out to give the energy gaps of JT5 and [ JT5 + Sn4+] as well as to simulate the electronic properties of the maximal absorption peaks. Notably, the sensor JT5 was successfully applied to monitoring Sn4+ in zebrafish, and the JT5 -loaded filter paper provided a solid-state platform for detecting Sn4+ by both naked eye and fluorescent methods. In summary, this work contributes to monitoring Sn4+ in organisms and solid-state materials and promotes understanding of Sn4+ functions in biological systems, environments, and solid-state materials. [ABSTRACT FROM AUTHOR]

Recalcitrant compounds resulting from anthropogenic activity are a significant environmental challenge, necessitating the development of advanced oxidation processes (AOPs) for effective remediation. This study explores the synthesis of cuprous oxide nanoparticles on cellulose-based paper (Cu2O@CBP) using Eucalyptus globulus leaf extracts, leveraging green synthesis techniques. The scanning electron microscopy (SEM) analysis found the average particle size 64.90 ± 16.76 nm, X-ray diffraction (XRD) and Raman spectroscopy confirm the Cu2O structure in nanoparticles; Fourier-transform infrared spectroscopy (FTIR) suggests the reducing role of phenolic compounds; and ultraviolet–visible diffuse reflectance spectroscopy (UV-Vis DRS) allowed us to determine the band gap (2.73 eV), the energies of the valence band (2.19 eV), and the conduction band (−0.54 eV) of Cu2O@CBP. The synthesized Cu2O catalysts demonstrated efficient degradation of methylene blue (MB) used as a model as recalcitrant compounds under LED-driven visible light photocatalysis and heterogeneous Fenton-like reactions with hydrogen peroxide (H2O2) using the degradation percentage and the first-order apparent degradation rate constant (kapp). The degradation efficiency of MB was pH-dependent, with neutral pH favoring photocatalysis (kapp = 0.00718 min−1) due to enhanced hydroxyl (·OH) and superoxide radical (O2·−) production, while acidic pH conditions improved Fenton-like reaction efficiency (kapp = 0.00812 min−1) via ·OH. The reusability of the photocatalysts was also evaluated, showing a decline in performance for Fenton-like reactions at acidic pH about 22.76% after five cycles, while for photocatalysis at neutral pH decline about 11.44% after five cycles. This research provides valuable insights into the catalytic mechanisms and supports the potential of eco-friendly Cu2O nanoparticles for sustainable wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Due to the inherent toxicity of cadmium selenide (CdSe)‐based quantum dots (QDs), Cd‐free alternatives are being widely investigated. Indium phosphide (InP) QDs have shown great potential as a replacement for CdSe QDs in display applications. However, the performance of InP‐based quantum dot light emitting diodes (QLEDs) is still far behind that of the CdSe‐based devices. In this study, we wanted to show the effects of different approaches to improve the performance of InP‐based QLED devices. We investigated the effect of magnesium (Mg) doping in ZnO nanoparticles, which is used as an n‐type electron transport layer, in balancing the charge transfer in InP‐based QLED devices. We found that an increasing Mg doping level can broaden the ZnO band gap, shift its energy levels, but most importantly, increase its resistivity; as a result, the electron current density is significantly reduced and the device efficiency is improved. We also investigated the effect of high‐photoluminescence quantum yield emitters and different QLED architectures on the device performance. Through optimizing QD structures and devices, red InP QLEDs with the current efficiencies reaching 11.6 cd/A and green InP QLEDs with the current efficiencies reaching 37.0 cd/A were fabricated. [ABSTRACT FROM AUTHOR]

For example: "peak intensity along the (1 0 0) plane" instead of correct "from the plane", "crystal orientation have changed with (...) concentration" - should be: crystallite orientation. Some remarks on the paper "Influence of zinc concentration on band gap and sub-band gap absorption on ZnO nanocrystalline thin films sol-gel grown" by Munirah, Ziaul Raza Khan, Anver Aziz, Mohd. (http://creativecommo ns.org/licenses/by- nc- nd/4.0/) MaterialsScience-Poland,38(3),2020,pp. 407-408 http://www.materialsscience.pwr.wroc.pl/ DOI:10.2478/msp-2018-0102 Some remarks on the paper "Influence of zinc concentration on band gap and sub-band gap absorption on ZnO nanocrystalline thin films sol-gel grown" by Munirah, Ziaul Raza Khan, Anver Aziz, Mohd. [Extracted from the article]

In the wake of increasing global emphasis on sustainable environmental practices, South African organisations strive to integrate green business principles into their strategies. The paper's objective was to evaluate the importance and implementation of an energy policy within the financial services sector in line with ISO50001. The paper presents findings from a quantitative non-experimental study within the South African financial services sector through a structured questionnaire. The findings showed that although the implementation of an energy policy is important, there is still a gap in the adoption of an energy policy within the financial services sector. The study further found that a notable percentage (29.5%) of respondents indicated that the energy policy did not provide sufficient guidance on energy targets and objectives. Setting an energy policy is the starting point and driving force for implementing energy management. It should be the priority of managers who have not yet done so. Further research on how energy policies are structured through content analysis could add value to organisations that have not yet implemented such policies. [ABSTRACT FROM AUTHOR]

Defects in organic light‐emitting diodes (OLEDs) generate the electronic states whose energy level are usually found in the energy gap of OLED materials. Hence, defects can disturb the movement of, and sometimes eliminate, the charges and excitons in OLEDs. Here, we discuss how the properties of the defects, i.e., their originating positions, energy levels and densities, affect the dynamics of the charges and excitons, thereby determining the electrical and optical performance of the comprising OLEDs. [ABSTRACT FROM AUTHOR]

ZnO and Zn(0.97-x)Al0.03MnxO (x = 0.00 (AlMnZ0), 0.04 (AlMnZ4), 0.05 (AlMnZ5) and 0.06 (AlMnZ6)) nanopowders that have been synthesized in powder form by using coprecipitation method at powder-based low temperature are zinc chloride (Sigma Aldrich), manganese (II) chloride tetrahydrate (Sigma Aldrich), and aluminum chloride hexahydrate (Sigma Aldrich). The powder of zinc chloride, aluminum chloride hexahydrate and manganese (II) chloride are dissolved in 0.5 M HCl, then a precipitating agent is added in the form of NaOH 5 M base into the solution by slowly dropping NaOH 5 M solution into the precursor until a pH of 10 is reached which causes the clear and transparent solution turns into milky white. In order for the reaction to run perfectly, the stirring process is carried out in a hot plate stirrer for 90 minutes at a temperature of 85 °C. After the solution is formed, it is washed with distilled water repeatedly until there is no impurities and it is filtered with filter paper to separate the precipitate from the solution. X-ray Diffraction (XRD) and Ultra Violet Visible (UV-VIS) Spectroscopy have been used to characterize ZnO nanopowder products through (Al+Mn) doping. The results show that AlMnZ0, AlMnZ4, AlMnz5 and AlMnZ6 nanopowder has the form of a hexagonal wurtzite crystal phase with a crystal size of ~38.03881-47.57561 nm. The optical band gap of ZnO nanopowder can be increased by atomic doping (Al+Mn). The increase in the optical band gap of AlMnZ0, AlMnZ4, AlMnZ5 and AlMnZ6 nanopowder is related to the Burstein-Moss effect, that is when (Al+Mn) atoms are successfully incorporated into ZnO nanopowders, there is a vacancy of the oxygen atom in the host crystal. [ABSTRACT FROM AUTHOR]

The basic concepts and phenomenology of wave mixing and harmonic generation are reviewed in context of the recent advances in the enhanced nonlinear activity in metamaterials and photonic crystals. The effects of dispersion, field confinement and phase synchronism are illustrated by the examples of the on-purpose designed artificial nonlinear structures. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22:469-482, 2012. [ABSTRACT FROM AUTHOR]

TiO2nano-powders were agglomerated by a spray drying process for application to thermal spraying. A conventional oxygen-acetylene flame torch was used to deposit porous partially nanostructured TiO2coatings. Steel substrates were used as a support for tested samples. Scanning electron microscopy, X-ray microanalysis and X-ray diffraction were performed to study the morphology and the crystalline phases of the titania coatings. Optical bandgap and kinetics of the acetone decomposition were also studied. The best results were obtained for the powder which is available as a commercial spray feedstock. This powder seems to be most resistant against the reducing atmosphere in the jet of combustive gasses. [ABSTRACT FROM AUTHOR]

The effect of the crystalline phase of TiO2(anatase, rutile and brookite) on its photocatalytic activity in hydrogen production from methanol–water vapours has been investigated by testing a series of both home-made and commercial TiO2photocatalysts, either bare or surface-modified by deposition of a fixed amount, i.e.1 wt%, of platinum as co-catalyst. For all of the TiO2samples the rate of hydrogen production increased by one order of magnitude upon Pt deposition, because of the ability of Pt to enhance the separation of photoproduced electron–hole pairs. Under irradiation in the 350–450 nm wavelength range, brookite and anatase showed similar photoactivities, both superior to that of rutile. By contrast, rutile, possessing a narrower band gap, was active also under visible light (λ> 400 nm), whereas no hydrogen evolution was observed with anatase and brookite under such conditions. Surface area proved to be a key parameter, strongly influencing photoactivity. However, as the particle size became ultra-small, the semiconductor absorption edge was blue-shifted because of size quantisation effects, with a consequent decrease in hydrogen production rate due to the smaller portion of incident photons absorbed by the photocatalyst. [ABSTRACT FROM AUTHOR]

Abstract: Germanium surface and interfaces are modeled based on the requirement that surface charge neutrality is satisfied. It is found that Ge interfaces have remarkable electronic properties stemming from the fact that the energy gap is low and the CNL is located very low in the gap close to the valence band. Because of this, acceptor defects (probably dangling bonds) are easily filled building a negative charge at the interface which easily inverts the surface of n-type Ge at no gate bias and for low doping ND and moderate to high interface state density Dit . This has important consequence in the electrical characteristics of Ge transistors. In p-channel FETs, an undesired positive threshold voltage VT of +0.2 to +0.5V is predicted depending on ND , Dit and the equivalent oxide thickness. In n-channel FETs, inversion is inhibited and VT could become higher than 1V if the Dit is well in excess of 1013 eV−1 cm−2. [Copyright &y& Elsevier]

This Special Issue of the IEEE Transactions on Electron Devices will feature the most recent developments and the state of the art in the field of ultra wide band gap semiconductors and devices for power control and conversion, including both experimental results and theoretical developments. Papers must be new and present original material that has not been copyrighted, published or accepted for publications in any other archival publications, that is not currently being considered for publications elsewhere, and that will not be submitted elsewhere while under considerations by the Transactions on Electron Devices. Topics of interest include, but are not limited to: IDtra Wide Band Gap Materials: Advances in material synthesis, defect characterization, transport and high-field properties, and material-level integration; evaluation of fundamental materials-limited figures of merit; Power Devices: Vertical and lateral MOSFETs, HEMTs and MIS-HEMTs, IGBTs, Schottky and pn junction rectifiers, and other device concepts; fabrication and device characterization; designs and device structures for controlling field profiles, edge termination; Thermal Management: Approaches to mitigate thermal effects in power devices using ultra wide band gap materials; Integration: Monolithic and heterogenous integration for system-level applications using ultra wide band gap materials. Integration with Si or other semiconductors for system-on-chip and system-in-package implementations, including heterogenous and package-level integration for high-performance power conversion applications. [ABSTRACT FROM AUTHOR]

In the present work, visible light active bismuth oxyiodide (BiOI) was immobilized on a commercial, non-conductive support (an Al2O3 based ceramic paper) using a novel two-step spray coating technique and investigated with different characterization methods (e.g., SEM, Raman, XPS). Our main goal was to eliminate the separation costs after the photocatalytic measurement and investigate the chemical relevance and opportunity to use this technique in the industry. Our as-prepared uniform BiOI layer had similar properties to the well-known reference BiOI powder. The Raman and XPS measurements confirmed that the enriched amount of the surface iodine defined the color and as well the band gap of the BiOI layer. The durable BiOI layers have prominent photocatalytic activity under UV and visible light irradiation as well. The scale-up procedure proved that the designed BiOI coated paper was reusable and potentially applicable in the industry by straightforward scale-up, which is due to the elaborated non-conventional BiOI coverage estimation method. This immobilization technique could open several opportunities for immobilizing many other visible light active photocatalysts with simple materials and low cost. [ABSTRACT FROM AUTHOR]

Meeting the growing demand for robust, earth-abundant and noble-metal-free photocatalysts for practical hydrogen-evolution reaction systems is crucial. Herein, cation modified perovskite niobates, Na0.5Sr0.5M0.25Nb0.75O3 (M = Cr, Mn, Fe, Co), are synthesized using a simple heterovalent coupled substitution strategy via solid-state reactions. The Cr compound as a single semiconductor system exhibits a photocatalytic hydrogen evolution rate of 188 μmol h−1 g−1, which significantly surpasses the performance of many contemporary catalysts that rely on the use of noble metal cocatalysts. Apparent quantum efficiencies (AQEs) of Cr, Mn, Fe and Co containing compounds are 2.24, 0.55, 0.65 and 0.74%, respectively. The photophysical properties like tuned band gap, suitable energy level positioning, charge carrier density, photostability of the materials and charge transfer resistance that are responsible for efficient spatial charge separation and charge transfer dynamics impacting the hydrogen evolution are investigated. This paper discusses the role of cation modification and its effects on the photophysical properties and hydrogen evolution activity of the perovskite niobates under noble-metal free conditions. These nonprecious noble-metal-free perovskite niobates furnish a new perspective for the future design of photocatalysts for efficient photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Co-doping of phosphorus and boron elements into crystalline silicon quantum dot (c-Si QD) is an effective approach for enhancing the photoluminescence (PL) performance. In this paper, we report on the preparation of hydrogenated silicon nitride (SiNx:H) thin films embedded with phosphorus-boron co-doped c-Si QDs via plasma enhanced chemical vapor deposition route. Mixed dilution including hydrogen (H2) and argon (Ar) is applied in the in-situ deposition process for optimizing the deposition process. The P-B co-doped c-Si QD/SiNx:H thin films exhibit a wide range of PL spectra. The emission is greatly improved especially for the short-wavelength light when compared to the SiOx:H thin film containing P-B co-doped c-Si QDs. The effects of H2/Ar flow ratio on the structural and optical characteristics of thin films are systematically investigated through a series of characterizations. Experimental results show that various properties, such as crystallinity, QD size, optical band gap and doping concentrations, are effectively controlled by tuning H2/Ar flow ratio. Based on the red-shift of QCE-related PL peak, the successful P-B co-doping into Si QDs are verified. Finally, a comprehensive discussion has been made to analyze the influence of H2-Ar mixed dilution on the film growth and impurity doping in detail in this paper. [ABSTRACT FROM AUTHOR]

In this paper, a NiAl-LDH with the characteristic structure of a hydrotalc-like compound was applied as a carrier in a two-step hydrothermal process, and a MnCdS/In2S3/NiAl-LDH composite material was successfully prepared by loading MnCdS and In2S3 on the flower spherical-like surface of NiAl-LDH. The combination of NiAl-LDH with In2S3 and MnCdS made the band gap smaller and the light absorption range larger, thus increasing the utilization rate of light. 50% MnCdS/In2S3/NiAl-LDH composites had the best photoinduced charge separation and highest surface enrichment of photogenerated electrons. In the degradation experiment of crystal violet (CV), 50% MnCdS/In2S3/NiAl-LDH composites showed superior photocatalytic degradation efficiency (>98.5%) under full spectrum light. Furthermore, the applicability and universality of photocatalysts were studied by observing the degradation of CV by MnCdS/In2S3/NiAl-LDH composites under different conditions. In addition, the composites showed excellent hydrogen production capacity in the photolysis of water, in which hydrogen production within 8 hours was about 7661.51 μmol g−1. By combining the results of active species capture experiments, density functional theory (DFT) calculations and photoelectrochemical experiments, the possible mechanism of double S-scheme heterojunction photocatalysis among NiAl-LDH, In2S3 and MnCdS was inferred, which is one of the main reasons for the enhancement of photocatalytic activity. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry." It includes the titles and authors of various articles published in the journal, covering topics such as the synthesis and reactivity of hydride complexes, sustainable copolymers, and the structure and behavior of various metal complexes. The journal is published by The Royal Society of Chemistry, a leading chemistry community. [Extracted from the article]

This paper reviews sintered silver (s-Ag) die-attach materials for wide band gap (WBG) semiconductor packaging. WBG devices that die-attach with s-Ag have attracted a lot of attention owing to their low energy loss and high temperature operation capabilities. For their practical operation, a reliability design should be established based on the failure of physics of the s-Ag die layer. This paper first focuses on the material characteristics of the s-Ag and tensile mechanical properties. Then, the s-Ag die-attach reliability is assessed with high-temperature storage, power cycling, and thermal shock tests. Each fracture mode was discussed by considering both the fracture surface analysis results and its mechanical properties. Finally, the effective reliability design parameters of the s-Ag die layer are introduced. [ABSTRACT FROM AUTHOR]

This paper proposes a full-duplex (FD) antenna design with passive self-interference (SI) suppression for the 28 GHz mmWave band. The reduction in SI is achieved through the design of a novel configuration of stacked Electromagnetic Band Gap structures (EBGs), which create a high impedance path to travelling electromagnetic waves between the transmit and receive antenna elements. The EBG is composed of stacked patches on layers 1 and 2 of a four-layer stack-up configuration. We present the design, optimization, and prototyping of unit antenna elements, stacked EBGs, and integration of stacked EBGs with antenna elements. We also evaluate the design through both HFSS (High Frequency Structure Simulator) and over-the-air measurements in an anechoic chamber. Through extensive evaluations, we show that (i) compared to an architecture that does not use EBGs, the proposed novel stacked EBG design provides an average of 25 dB of additional reduction in SI over 1 GHz of bandwidth, (ii) unit antenna element has over 1 GHz of bandwidth at −10 dB return loss, and (iii) HFSS simulations show close correlation with actual measurement results; however, measured results could still be several dB lower or higher than predicted simulation results. For example, the gap between simulated and measured antenna gains is less than 1 dB for 26–28 GHz and 28.5–30 GHz frequencies, but almost 3 dB for 28–28.5 GHz frequency band. [ABSTRACT FROM AUTHOR]

The flexible photodetector plays an important role in improving human medical health status. However, the narrow spectral detection range, poor stress stability, and non‐degradation of traditional flexible photodetectors greatly hinder the further development of wearable medical devices. In this paper, a novel flexible infrared photodetector is proposed for intelligent healthcare monitoring using high purity lead sulfide (PbS) nanoparticles on paper‐based flexible substrate synthesized by hydrothermal method and physical friction. The excellent performance of the detector is attributed to the 1.01 eV band gap and six‐arm stellate dendritic structure of PdS, a good combination between PbS and paper substrate via physical friction. As a result, our photodetector demonstrates wide‐spectrum detection capabilities from 365 to 1550 nm. The photodetector at 980 nm (50.4 μW cm−2) shows responsivity of 6.45 mA W−1, detectivity of 6.4 × 1010 Jones, response recovery time of 0.36 s/0.41 s, with good mechanical stability. By comparison, our detector has a wider detection range, better weak signal detection performance, and shorter response time than the performance of the former paper‐based detector. Furthermore, the paper‐based PbS photodetector as a dual‐wavelength photoplethysmography sensor is applied to analyze the oxygen saturation and develop an intelligent bandage to monitor wound healing. This paper‐based PbS photodetector has tremendous potential in the field of wearable medical devices and intelligent medical applications are expected. [ABSTRACT FROM AUTHOR]

Functionalized graphene oxide papers are assembled materials with a wide range of potential applications; however, scientific studies about how the physical properties of functionalized graphene oxide papers are affected by the presence of new functional groups have not been addressed. Here, electrical resistance, optical band gap, and mechanical properties of flexible and free-standing functionalized graphene oxide papers with nitroxide moieties (NGOP's) have been studied, and two of them (mechanicals and electricals) were correlated with the interlayer d spacing for the first time; herein, a new insight about the key role that an optimum amount of functionalization agent plays over the physical properties of NGOP's is presented. In all cases, (functionalized or pristine) graphene oxide papers were prepared using anhydrous DMF instead water in order to study and highlight the pure effect of the functionalized groups over their physical properties. The functionalized nanomaterials exhibited significantly improved physical properties, which can be tuned by varying the interlayer d spacing, and this interlayer distance was systematically modified controlling the amount of functionalizing agent used. Thus, controlling the amount of functionalizing agent in the functionalization process is possible to obtain new assembled materials with modulated properties. [ABSTRACT FROM AUTHOR]

The widespread use of antibiotics leads to the pollution of the water environment. Photocatalytic technology is considered as an effective way of removing antibiotics from the water environment. In this paper, a semi-embedded CdS/tubular g-C3N4 (CdS/TCN) heterojunction photocatalyst was designed and prepared by hydrothermal, in situ oil bath and thermal polymerization methods. Then Ni nanoparticles were loaded onto the surface of CdS/TCN by an in situ photoreduction method to form high performance photocatalyst Ni–CdS/TCN. The degradation rate of tetracycline hydrochloride (TCH) by Ni–CdS/TCN-6 was about 1.9 times higher than that of bulk carbon nitride (BCN) under visible light irradiation for 30 min. The high specific surface area, the effective heterojunction and loaded Ni broaden the light absorption range, narrow the band gap and improve the photogenerated carrier separation efficiency and migration rate. Beyond that, loaded Ni also inhibits photocorrosion and improves the stability of the photocatalyst. The present work provides a new way for designing a semi-embedded heterojunction photocatalyst. [ABSTRACT FROM AUTHOR]

The research addresses the pressing need to understand wind conditions for optimal wind energy utilization, a crucial aspect of achieving global energy sustainability. While previous studies have focused on assessing wind energy potential and terrain roughness, gaps persist in understanding how wind and spatial conditions affect blade geometry. Therefore, this study aims to investigate the impact of local wind conditions on wind turbine blade geometry, integrating nonuniform wind inflow due to wind shear into the theoretical model. Through the paper, it explores blade design for varying inflow conditions and analyses the relationship between terrain type and blade designs. A novel approach to wind turbine blade design, utilizing a theoretical model that combines the local momentum theorem with insights from propeller vortex theory was adopted. Through the analysis, the authors demonstrate that variations in terrain significantly influence blade geometry, underscoring the necessity for tailored turbine designs based on local conditions. The findings reveal discrepancies in blade geometry across different turbine capacities and terrain types, offering novel insights into wind turbine performance optimization. By tailoring blade geometry to specific locations enhances resource utilization, offering insights for energy policymakers. The research provides validated methods for optimizing turbine geometric parameters, opening avenues for increased local investment in wind energy and promoting distributed energy development. Illustrated with wind plants examples, the paper concludes by outlining future research directions in this field. [ABSTRACT FROM AUTHOR]

In the present paper, we have conducted both theoretical and experimental investigations on thin films of lead sulfide (PbS). The structural and morphological properties of these films, which were prepared using the spray pyrolysis method, were analyzed utilizing X-ray diffraction (XRD) and scanning electron microscopy (SEM). Theoretical calculations were performed employing the first principles full potential linearized augmented plane wave (FP-LAPW) approach. The findings of this study reveal that the PbS film that was deposited is polycrystalline and possesses a rock-salt structure. The SEM image depicts a planar structure with dimensions ranging from 480 to 930 nm. The results obtained through energy dispersive spectroscopy (EDS) indicate high crystalline quality, and the film surface exhibits a rough texture and a dense morphology. In terms of its behavior, PbS acts as a semiconductor with a direct optical band gap situated at the L point of the Brillouin zone (BZ). The density of states on both sides of the band gap is primarily of s-p character. The ionic nature of PbS can be attributed to charge transfer. A substantial level of agreement has been observed between the experimental and theoretical results. Our ongoing research endeavors aim to explore biosensors and their various applications. The novelty of this work lies in the combined study of the structural and morphological properties of PbS films grown using the spray pyrolysis technique, employing both experimental and theoretical approaches. This paper describes a comprehensive approach to understanding bulk and thin-film PbS materials through theory and experimentation. [ABSTRACT FROM AUTHOR]

Periodic structures are a type of metamaterial in which the physical properties depend not only on the details of the unit cell but also on how unit cells are arranged and interact with each other. In conventional engineering structures, each unit cell interacts with adjacent cells. Methods developed for vibrational and wave propagation analysis in periodic engineering structures consider only nearest-neighbor interactions. The dispersion curves of such systems, in which only adjacent cells interact, have been extensively studied. Metamaterial properties depend on the interactions of a unit cell with other cells. Further interactions, and specifically, interactions beyond the closest neighbors, imply a more complex band structure and wave behavior. In this paper, an example class of such structures, in which electrostatic forces are the driving force, has been investigated. In this paper, properties affecting these periodic structures, such as elastic forces, have been investigated. An attractive property of such structures is that the band structures of such metamaterials can be tuned by changing electric voltages. [ABSTRACT FROM AUTHOR]

This paper reports on the photodegradation of the Rh 6G dye using a g-C3N4 (g-CN) nanosheet photocatalyst under UV light irradiation. The g-C3N4 nanosheets were synthesized using a simple pyrolysis method at 450 °C for 3 h at a heating rate of 2 °C min−1. Their structural phase, functional groups, surface area, optical properties, elemental composition, and morphology were investigated via XRD, BET, UV-vis, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and SEM microscopy. The tri-s-triazine structure of g-C3N4 was confirmed and the crystal size was calculated to be 5 nm. g-C3N4 displayed a nanosheet morphology with a BET surface area of 8 m2 g−1. C–N stretching and s-triazine units were observed in the FTIR spectrum. The photoluminescence (PL) emission maximum at 432 nm provided band edge emission related to a band gap of 2.9 eV, and the PL lifetime was 7.6 ns, which is reasonably high for photocatalytic application. Through the C1s XPS spectrum, sp2-hybridized carbon linkages of N–C＝N in the aromatic skeleton rings, such as triazine or heptazine rings, of g-C3N4 were found. The photocatalytic characteristics of g-C3N4 were studied with the Rh-6G dye using UV light illumination. Initially, the Rh-6G dye concentration and catalyst (g-C3N4) loading were optimized for the best dye degradation at 0.01 mmol and 50 mg, respectively. The maximum efficiency of g-C3N4 was 99.6% degradation of the Rh-6G dye in 300 minutes. Lower charge-transfer resistance was found to be the reason for the enhanced photodegradation activity. The most dominant reactive species that participated in the light-activated reaction were superoxide radicals. The influence of pH on photodegradation was studied and the photocatalyst was found to perform better in an acidic pH range. In addition, g-C3N4 was structurally stable, highly recyclable, and, therefore, could be reused in many cycles of photocatalysis. [ABSTRACT FROM AUTHOR]

In this paper, the structural, electrical and optical effects of WS2 doped with silicon atoms after torsional deformation are investigated using first-principles calculations. First-principles calculations for metal disulfide-WS2. The doping of Si atoms gives WS2 a tunable band gap, and the surface state is successfully transformed from a 2.0 eV band gap to a quasi-metal with a 0.254 eV band gap, and the change of the doped Si atoms causes a redshift in the absorption peak and a blueshift in the reflection peak. The band gap of WS2 can be effectively adjusted by torsional deformation on the basis of Si-doped atoms in the range 0.254–0.052 eV. Calculations of optical properties show that Si-doped WS2 with a torsion angle of 1 0 ∘ has the lowest light absorption peak and Si-doped WS2 with a torsion angle of 8 ∘ has the lowest light reflection peak. This paper opens up new possibilities for designing materials on demand. [ABSTRACT FROM AUTHOR]

Vibration and noise pollution is one of the main pollution in modern society. In order to obtain good vibration damping effect, more effective phononic crystals should be designed. Based on the theory of elastic wave propagation in solids, three types of phononic crystals are designed in this paper using tungsten blocks embedded in a rubber matrix, which are cup-shaped phononic crystal, solid cylindrical phononic crystal, and hollow cylindrical phononic crystal. Firstly, the band gap characteristics and vibration losses of the three phononic crystals are analyzed by using the finite element method. Secondly, the physical mechanism of band gap formation is explored by vibration modes. Finally, the cup-shaped phononic crystal was introduced into the core layer of the sandwich plate to form the cup-shaped phononic crystal sandwich plate, and its vibration damping performance was analyzed. The results show that the three phononic crystals can form three band gaps in the range of 0–800 Hz, and the first low-frequency band gap starts at about 140 Hz and is all wider than 200 Hz. It is noteworthy that the average loss of vibration transmission of the three types of phononic crystals is more than 69 dB, which possesses stronger damping capability and wider low- and middle-frequency band gaps than the flat plate type phononic crystals. The vibration direction of the phononic crystal is at an angle of 90° to the wave vector, which prevents the propagation of elastic waves. The phononic crystal embedded in the sandwich panel plate is more in line with the actual demand of vibration damping and obtains good vibration damping effect. The research in this paper can provide more feasibility for phononic crystal damping. [ABSTRACT FROM AUTHOR]

The geometrical and electronic parameters of 2-arylamino-4-(3-coumarinyl)thiazoles have been computed theoretically using the Gaussian 09W package of program using B3LYP/6-31G level of theory. The calculated geometrical parameters of 2-arylamino-4-(3-coumarinyl)thiazoles are comparable with the values reported for compounds of similar structure. Optimization reveals that the geometrical parameters are based on the size of the atom, bonding nature and charge transfer. The calculated MOs are supportive to establish the collective electronic properties of the optimized compounds. However, energy gap is an indicator of chemical reactivity, kinetic stability and polarizability. [ABSTRACT FROM AUTHOR]

[Display omitted] • GABA-derived CDs: Synthesis & purification by column chromatography. • CDs with green emission in solution & yellow solid-state emission under UV light. • Theoretical studies to support structural, vibrational, & electronic features of CDs. • Flexo-prints with good lightfastness, stability & rub resistance using water-based ink. • Forger sees yellow fluorescence & user authentication by Cu2+ ion induced quenching. Forgery of valuable products causes a negative impact on the society as well as the economy of the country. There is a growing demand to not only differentiate or authenticate genuine documents/products but also to protect their integrity. Carbon dots (CDs) are a class of fluorescent nanomaterials that are well-known for their facile synthesis, good photostability and less toxicity profile. The current research work focuses on the preparation of CDs via hydrothermal method using γ-aminobutyric acid (GABA) that contains amino and carboxylic groups. Column chromatography technique is adopted to purify the GABA-derived CDs from the reactants and by-products. The fourth fraction obtained after column purification containing CDs with fluorescence emission in the visible region is chosen for further studies. The presence of spherical CDs confirmed through TEM imaging are chemically characterised using SAED, EDS, DLS, FTIR, XPS, Raman and XRD spectroscopy. The blue (λ em = 490 nm) and green (λ em = 538 nm) emitting CDs present in the fourth fraction displayed a fluorescence lifetime of 1.90 ns and 2.02 ns. Theoretical studies are performed using B3LYP/6-31G(d,p) theory level on different plausible structures. The HOMO-LUMO band gap of 2.3 eV deduced using DFT calculation is in close agreement with the optical band gap of 2.6 eV derived from Tauc plot. A complex forming mechanism is proposed for the fluorescence quenching of CDs upon examining the EDS data of the precipitate obtained upon addition of cupric ions. Further, the CDs are used as pigments to formulate a water-based ink for flexographic printing on UV-dull paper substrate. The printed samples exhibited good colorimetric values, lightfastness, and rub resistance. The security features of the ink film include an UV-induced yellow fluorescence, which will be known to the forger and a secondary quenching of fluorescence when exposed to cupric ions, which can be used by the user to validate document/product authenticity. This stimulus responsive optical property is also explored in the design of ionochromic security paper based on cupric ion induced fluorescence quenching of CDs for data storage and decryption. Moreover, the lesser surface roughness and electrical parameter values obtained for the print proofs could be further explored for the potential application of CD-derived ink in electronic anticounterfeiting. [ABSTRACT FROM AUTHOR]

As a new generation of photoelectric materials, organic-inorganic halide perovskites have been widely used in photodetectors, solar cells and other fields, but most of the current mainstream applications are thin film materials. Compared with polycrystalline thin films, perovskite single crystals have fewer grain boundaries and relatively stable electron and hole transport, and are ideal materials for optoelectronic devices. To realize the controllable growth of CH3NH3PbBr3 (MAPbBr3) crystals, understand their growth mechanism, and reflect the inherent physical and chemical properties of the material, a new type of internal growth temperature control and external circulation cooling growth system was developed in this paper, which can accurately control the temperature change during crystal growth. The size of the grown MAPbBr3 single crystal reaches 62 × 58 × 23 mm³, which is the largest single crystal reported to date. The measured single crystal absorption cut-off edge, optical band gap, and carrier lifetime are superior to the traditional simple inverse temperature crystallization (ITC) method, which will help its deep applications in photovoltaics, optoelectronics, and X-ray imaging. [ABSTRACT FROM AUTHOR]

The study of optical topological insulators (PTIs) has revealed intriguing optical properties that diversify the ways in which light can be manipulated, offering significant potential for a wide range of applications. This paper presents a machine learning (ML)-based approach for the reverse design of optical PTIs. Using finite element methods, the paper addresses the challenge of computing the band structure of a dual-band model, enabling the construction of a dataset suitable for ML training. With the goal of maximizing dual-band bandgaps, the study employs the random forest algorithm to predict target parameters and further designs topological edge states. Leveraging these boundary state patterns, two different optical PTI beam splitters are devised, and their transmission coefficients and losses are computed. The results demonstrate that optical devices designed using topological boundary states exhibit enhanced stability and robustness. This approach offers a reliable solution for applications in fields such as optical communication and optical sensing. [ABSTRACT FROM AUTHOR]

Phosphates, whose obvious disadvantage is the relatively small birefringence, can be overcome by the introduction of post-transition metal cations containing stereochemically active lone-pair electrons. In this paper, two new compounds were successfully explored in the A–Sb–P–O system, i.e. Cs2Sb3O(PO4)3 (CsSbPO) and (NH4)2Sb4O2(H2O)(PO4)2[PO3(OH)]2 (NH4SbPOH). Transmission spectra show that CsSbPO has a surprising transmission range with a UV cutoff edge of 213 nm. First-principles calculations show that both compounds have a wide band gap (5.02 eV for CsSbPO and 5.30 eV for NH4SbPOH) and enlarged birefringence (Δn = 0.034@1064 nm for CsSbPO and Δn = 0.045@1064 nm for NH4SbPOH). The results of real-space atom-cutting investigations show that the distorted [SbOx] polyhedra originating from the asymmetric lone pair electrons give the main contribution to the total birefringence and overcome the disadvantage of small birefringence of phosphates but maintain wide transition windows. [ABSTRACT FROM AUTHOR]

The primary objective of this paper is to conduct a comparative analysis of diverse Electromagnetic Band Gap (EBG) antennas in terms of their suitability for Wi-Fi applications operating at 5 GHz. Wi-Fi primarily operates within the 2.4 GHz and 5 GHz frequency bands, with the 5 GHz band offering higher data rates and reduced interference compared to the 2.4 GHz band. Furthermore, its larger number of available channels makes it an optimal choice for environments with high user density. The antennas in this study are designed with dimensions of 28.11x32.40x1.6 mm³ (length x width x height) using RT/Duroid 5880 substrate, which has a thickness of 1.6 mm and a relative permittivity (εr) of 2.2. The integration of Electromagnetic Band Gap structures in antenna designs has gained substantial attention due to their unique properties that enhance antenna performance characteristics. The paper presents sixteen distinct EBG antennas, all designed using CST software. These antennas incorporate various EBG shapes, such as Fork, L-shape, C-shape, Hash, and Z-shape, positioned on a rectangular patch and in the ground plane. The study's results reveal that the Hash EBG on the patch offers superior performance compared to other EBG types. As a result, the Hash EBG on the patch, alongside various Z-shaped EBGs on the ground plane, is assessed for different antenna performance parameters, including return loss, radiation patterns, and gain. Finally, a diagonal Z-shaped EBG antenna is designed, simulated, and tested. The antenna return loss at 5.2GHz is –48 dB The proposed antenna achieved a peak gain of 7.3 dB at 5.2GHz. The proposed antenna exhibits omnidirectional properties. The antenna shows an efficiency of 90% at the resonant frequency. The experimentally measured results of the designed diagonal EBG antenna have shown satisfactory agreement and are consistent with the simulated results. The findings of this research contribute to a better understanding of EBG antennas potential for Wi-Fi applications in the 5 GHz frequency band. [ABSTRACT FROM AUTHOR]

In this paper, a multi-layered mushroom-type electromagnetic band gap (EBG) structure is proposed. A double layer two via EBG (DLTV EBG) structure is designed at 1.65 GHz. The proposed DLTV-EBG structure consists of a two-layer dielectric substrate, which reduces the lateral sizes due to a multilayer topology. By adjusting the patch dimensions and positions of the vias, the center frequency, and equivalent L and C parameters meet design requirements. In a DLTV-EBG, layer-1 has a square ring patch; layer-2 has a circular ring; outer square ring patch with 2 edged located vias gives the additional capacitance and inductance to achieve compactness. The simulation of the DLTV-EBG structure is carried out using the Ansys high-frequency structure simulator (HFSS) and experimentally validated. The band gap of the DLTV-EBG structure is measured using suspended microstrip line (SML) method. The Experimental results agree well with simulation one. The periodic size of the proposed DLTV-EBG structure is 0.05λ1.65 GHz, which is a good candidate where compact size is highly desired. [ABSTRACT FROM AUTHOR]

The oxide and halide perovskite materials with a ABX3 structure exhibit a number of excellent properties, including a high dielectric constant, electrochemical properties, a wide band gap, and a large absorption coefficient. These properties have led to a range of applications, including renewable energy and optoelectronics, where high-performance catalysts are needed. However, it is difficult for a single structure of perovskite alone to simultaneously fulfill the diverse needs of multiple applications, such as high performance and good stability at the same time. Consequently, perovskite nanocomposites have been developed to address the current limitations and enhance their functionality by combining perovskite with two or more materials to create complementary materials. This review paper categorizes perovskite nanocomposites according to their structural composition and outlines their synthesis methodologies, as well as their applications in various fields. These include fuel cells, electrochemical water splitting, CO2 mitigation, supercapacitors, and optoelectronic devices. Additionally, the review presents a summary of their research status, practical challenges, and future prospects in the fields of renewable energy and electronics. [ABSTRACT FROM AUTHOR]

Exploration of compounds featuring multiple anions beyond the single-oxide ion, such as oxyhalides and oxyhydrides, offers an avenue for developing materials with the prospect of novel functionality. In this paper, we present the results for a mixed anion layered material, ScHX2 (X: Br, I) based on density functional theory. The result predicted the ScHX2 (X: Br, I) monolayers to be stable and semiconducting. Notably, the electronic and mechanical properties of the ScHX2 monolayers are comparable to well-established 2D materials like graphene and MoS2, rendering them highly suitable for electronic devices. Additionally, these monolayers exhibit an ability to adjust their band gaps and band edges in response to strain and substrate engineering, thereby influencing their photocatalytic applications. [ABSTRACT FROM AUTHOR]

Purpose: Despite the number of quality management procedures being currently applied, construction defects in the domestic sector are acknowledged to contribute to the energy performance gap of buildings. This paper investigates the limitations and challenges to the implementation of project quality plans (PQPs) and their impact on the achievement of expected thermal performance in the UK social housing projects. Design/methodology/approach: A qualitative approach, guided by grounded theory, was used in this research. This methodology provided the structure for systematic data analysis iterations, enabling cross-case analysis. An analytic induction process was designed to seek the explanation of the targeted phenomenon and required data collection until no new ideas and concepts emerged from the research iterations. This study collected data from five social housing projects through interviews, site observations and project documentation. Findings: Multiple limitations and challenges were identified in the implementation of PQP to deliver thermal efficient social housing. Generally, there is the need for more objective quality compliance procedures based on required evidence. When investigating the root of the challenges, it was concluded that the adoption of statutory approval as the main quality compliance procedure led to the dilution of the responsibility for prevention and appraisal of defects that compromised the effectiveness of PQP devised by housing associations (HA) and contractors. Originality/value: This study identifies the shortcomings of PQP in addressing quality issues with potential to undermine the thermal performance of social housing projects. The findings could be used by HA, contractors and policymakers as steppingstones to improve the energy efficiency in the domestic sector. [ABSTRACT FROM AUTHOR]

In the present work, Al-doped (0, 1, 2 and 3%) ZnO nanoparticles (NPs) are synthesised by green combustion method (GCM) using Terminalia Catappa seeds (TCS) extract as a novel fuel. For the synthesis Zinc nitrate and Aluminum nitrate are used as precursor and dopant respectively. The synthesised NPs are characterised by XRD, FTIR, UV-vi and impedance spectroscopy. The XRD analysis shows decrease in crystallite size varies between 40 to 26 nm as dopant increases. The FTIR spectrum reaffirms the formation of Zn-O bonding structure at 454.28 cm−1. UV-Vi spectroscopic studies show the optical band gap of 3.63, 3.53, 3.22 and 3.19 eV for Al doped (0, 1, 2 and 3%) ZnO NPs. Thermal analysis for the synthesised Al-doped (0, 1, 2 and 3%) ZnO nanoparticles are analysed using TGA/DTA studies. The Electrical characteristics are studied at various temperatures (50 to 350°C) by varying frequency (10 Hz to 8 MHz). In low frequency regions, dielectric constant and dielectric loss increases with rise in temperature. The constant AC conductivity is observed in lower frequencies and increases for higher frequencies for all doped ZnO NPs. ZnO NPs prepared with 2% of doping exhibit improved structural and electrical properties. Hence these ZnO NPs may be used as sensing material for vibration sensor. Highlights: This paper focus on green synthesis of undoped and Al-doped ZnO nanoparticles by combustion method. ZnO nanoparticles are synthesised using zinc nitrate precursor, Aluminium nitrate as dopant and Terminalia catappa seed extract as fuel. Effect of Al (0, 1,2 and 3%) doping on microstructural, optical, thermal and electrical properties of ZnO nanoparticles are investigated. The green synthesised doped and undoped ZnO nanoparticles exhibit hexagonal wruzite structure with high crystallinity. The FTIR spectrum reaffirms the formation of Zn-O bonding structure at 454.28 cm-1 The optical band gap is found to be 3.63, 3.53, 3.22 and 3.19 eV for 0, 1,2 and 3% of Al doped ZnO nanoparticles respectively. AC conductivity of ZnO nanoparticles is found to be increased with 2% of Al doped ZnO nanoparticles. Result shows an improved structural, optical and electrical performance for 2% Al doped ZnO nanoparticles and hence these nanoparticles are suitable material for sensors, organic light emitting diodes and liquid crystal displays. [ABSTRACT FROM AUTHOR]