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The present study focused on to determine the concentration and health risk of heavy metals (Cu, Pb, Zn, Cd, Hg, Cr) in e-waste contaminated soils collected from different provinces of Pakistan. Further, the impact of heavy metals on soil enzyme activities and microbial community was also investigated. The concentration (mg/kg) of Hg, Zn, Fe, Cu, Pb, Cd, and Cr ranged between 0–0.258, 2.284–6.587, 3.005–40.72, 8.67–36.88, 12.05–35.03, 1.03–2.43, and 33.13–60.05, respectively. The results revealed that Lahore site of Punjab province indicated more concentration of heavy metals as compared to other sites. The level of Cr at all sites whereas Hg at only two sites exceeds the World Health Organization standards (WHO) for soil. Soil enzyme activity exhibited dynamic trend among the sites. Maximum enzyme activity was observed for urease followed by phosphatase and catalase. Contamination factor (Cf), Pollution load index (PLI), and geo-accumulation index (Igeo) results showed that all the sites are highly contaminated with Cu, Cd, and Pb. Hazard index (HI) was less than 1 for children and adults suggesting non-carcinogenic health risk. Principle component analysis results depicted relation among Cr, Fr, catalase, and actinomycetes; Cd, OM, urease, and bacteria, and Pb, Cu, Zn, Hg, and phosphatase, suggesting soil enzymes and microbial community profiles were influenced by e-waste pollution. Therefore, there is a dire need to introduce sustainable e-waste recycling techniques as well as to make stringent e-waste management policies to reduce further environmental contamination. [ABSTRACT FROM AUTHOR]

Researchers have focused on fabricating energy storage equipment to tackle global energy concerns. The energy storage systems including capacitors and batteries have several limitation because of their poor electrochemical performance. The electrode material’s suitability for supercapacitor depends on its ability to improve electrochemical performance and stability. In this work, CuS@g-CN (graphitic carbon nitride) composite was developed via a hydrothermal approach. Several analytical techniques were utilized to determine performance of the prepared CuS@g-CN composite. The specific capacitance of CuS@g-CN composite was 996 F/g which displayed stability after 10,000th cycles with a retention of 93% calculated from galvanostatic charge–discharge profiles. A charge transfer resistance of 1.18 Ω of CuS@g-CN composite was found relatively lower than individual materials calculated from the Nyquist plot. The nitrogen-rich structure of g-CN permits rapid ion transportation and the presence of multiple transition metals led to improved electrochemical effectiveness. The enhanced characteristics of CuS@g-CN composite render it suitable for incorporation into future energy storage devices. [ABSTRACT FROM AUTHOR]

Context: The world's energy and environmental requirements are changing due to rapid population growth and industrial growth, and solar cells can be used to meet these demands. Dye-sensitized solar cells (DSSCs) are solar cells in which energy conversion occurs via a process similar to photosynthesis in plants. DSSC development is still in its infancy. DSSCs can operate under cloudy conditions and indirect sunlight and have attracted considerable attention due to their low cost and high efficiency. We designed two metal-free TPA-based dyes (Dye2 and Dye3) based on the reference dye Mg207 (Dye1) by increasing the donor strength of the molecule, as such dyes have shown enhanced efficiency in DSSCs. Moreover, the triphenylamine (TPA) moiety has been demonstrated to be a good donor that prevents charge recombination. Intramolecular charge transfer (ICT) from the donor to acceptor moiety was found in the sensitizers, and electrons were promoted to the conduction band (CB) of the TiO2 semiconductor. The negative binding energy of the dye@TiO2 clusters indicated that dye adsorption on the semiconductor surface was stable. The double donor increased the electron injection and electronic coupling constants in Dye2 and Dye3, indicating that these newly designed dyes have superior charge injection capacity. Accordingly, the efficiencies of DSSCs with Dye2 and Dye3 were 9.77% and 9.62%, respectively, and substitution with the TPA unit at the -R1 and -R2 positions in Dye1 resulted in better power conversion compared to the parent compound (9.09%). Increased donor strength improved photovoltaic performance by increasing current density and light-harvesting efficiency. This is a good molecular design approach for preparing targeted donor- π -acceptor (D- π -A) organic dyes with high DSSC efficiency. Methods: To predict the charge transport and optoelectronic characteristics of the TPA dyes, quantum chemical calculations were carried out using Gaussian16. The ground-state (S0) optimized geometries of the sensitizers were computed by utilizing DFT at the B3LYP/6-31G** level. The absorption spectra (λ max) were computed by employing TD-DFT with various functionals (B3LYP, PBE1PBE, CAM-B3LYP, and BHandHLYP) in the gas and solvent (DCM) phases. Among the studied functionals, BHandHLYP was found to be best at successfully reproducing the experimental data. Thus, the absorption spectra of the newly designed dyes and dye@TiO2 were calculated at the BHandHLYP/6-31G** level. The dye@TiO2 cluster optimizations were carried out at the B3LYP/6-31G**(LANL2DZ) level. [ABSTRACT FROM AUTHOR]

The development of an inexpensive, efficient, and sustainable material suitable for energy storage applications is the need of modern era. Due to their affordability, eco-friendliness, high efficiency, and unique electronic structure metal oxides are the favorable candidate for this purpose. Here, the most desirable MnO2/ZnO nanocomposites were fabricated via hydrothermal route. The successful fabrication of synthetic material was confirmed via X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope, Raman spectroscopy, and X-ray photoelectron spectroscopy by analyzing the crystal structure, functionality, morphology, chemical property, and electronic properties. The electrochemical study was carried out in 1.0 M KOH (alkaline media) to assess the electrochemical performance of the fabricated composite materials for oxygen evolution reaction (OER) and supercapacitors. For this purpose, several various tests, like cyclic voltammetry, linear sweep voltammetry, galvanostatic charge discharge, and electrochemical impedance spectroscopy were performed. The electrochemical results revealed that the fabricated MnO2/ZnO nanocomposite has a Tafel slope and overpotential of 33.7 mV dec−1 and 274 mV, respectively. The small values of the Tafel slope and overpotential confirmed that our fabricated MnO2/ZnO nanocomposite is a potential candidate for OER. Moreover, the resultant MnO2/ZnO nanocomposite has a specific capacitance of 1038.3 F g−1 and a power density of 396.3 Wh kg−1. All these results confirmed that the fabricated MnO2/ZnO nanocomposite is a potential candidate for energy storage applications. [ABSTRACT FROM AUTHOR]

The sol-gel method was used to synthesize pure ZnO and MoO4@ZnO nanostructures for dual functionality in supercapacitors and photocatalysis. The material properties were examined using photoluminescence spectroscopy (PL), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDX). A PL study showed the presence of an intense peak centering approximately around 405 nm, which is primarily due to the near-band edge emission of ZnO excitonic recombination. XRD confirmed the formation of the ZnMoO4 crystal system. The SEM showed uniformed nano-flakes which was validated by EDX analysis having typical peaks of Zn, O, and Mo. The synthesized materials were evaluated for bi-functional application, including energy storage and photocatalytic degradation of methylene blue (MB) under solar irradiation. The 5% MoO4@ZnO nanomaterials showed uniform nanoflakes morphology with remarkable photocatalytic as well as electrochemical excellence. Notably, the 5% MoO4@ZnO nanomaterial degraded MB about 90.02% within 200 min. Galvanostatic charge discharge (GCD) exhibited an outstanding specific capacitance of 1026 F/g at 1 A/g for 5% MoO4@ZnO. The columbic efficiency of the 5% MoO4@ZnO electrode material was assessed until 2000 cycles, that retains its stability about 87%. The cyclic voltammetry was also assessed for the calculation of specific capacitance and energy density. The 5% MoO4@ZnO depicted excellent capacitance and energy density about 915.62 F/g and 53.72 Wh/kg respectively. This study showed that 5% MoO4@ZnO is a suitable candidate with the exceptional dual function that can be employed for the development of next-generation energy storage and photocatalysis. Highlights: Sol-gel method was used to synthesize pure ZnO and MoO4@ZnO nanostructures SEM showed the uniformity of nanoflakes in synthesized materials 5% MoO4@ZnO nanomaterial had excellent photocatalytic activity about 90.02% Galvanostatic charge discharge exhibited an outstanding specific capacitance of 1045 F/g at 1 A/g [ABSTRACT FROM AUTHOR]

In order to meet the demands of humanity and address the global environmental situation, it is imperative that we explore alternative energy sources and advance energy storage technology. The aim of this study was to investigate the impact of Nd-doping on the structural and electrochemical performance of FeAl2O4 nanoparticles (NPs). The successful synthesis of Nd-doped FeAl2O4 NPs) was accomplished through a simple sonication process. An evaluation was conducted on the properties of Nd-doping FeAl2O4 NPs) to determine their suitability for supercapacitor (SC) applications. Moreover, the specific capacitance (Cs) of Nd-doped FeAl2O4 NPs) reaches a maximum of 1194.69 F g−1 when subjected to a current density of 1.0 A g−1 compared to FeAl2O4 nanoparticles. Furthermore, Nd-doped FeAl2O4 NPs exhibited excellent cyclic stability and low impedance (Rct = 0.07 Ω), owing to their modified morphology, making a promising material for supercapacitor SC electrodes that offer high capacity, affordability, and environmental friendliness. Our research has validated that the synthesized material can enhance the capacitive properties of transition-metal oxides with spinel structures in new, generated energy storage devices. [ABSTRACT FROM AUTHOR]

The photovoltaic properties of a monocrystalline silicon solar cell were investigated under dark and various illuminations and were modeled by MATLAB programs. According to AM1.5, the studied solar cell has an efficiency rate of 41–58.2% relative to industry standards. The electrical characteristics (capacitance, current–voltage, power-voltage, transient photovoltage, transient photocurrent, and impedance) of a silicon solar cell device were examined. Under complete darkness and light intensity of 100 mW/cm2, respectively, we have noticed that the light of the AM1.5 spectrum changes all PV-cell parameters such as short current, open circuit voltage, maximum power, maximum voltage, and power conversion efficiency. An electrical equivalent circuit (R1//C1 + R2//C2) was used by the Zview software to fit the experimental data of the Nyquist representations (-Z'' vs. Z'). By analyzing the peak of the conductance Gp versus frequency, the density of interface states and the interface trap time constant were calculated. By using MATLAB programs, we have modeled the current versus voltage and power versus voltage properties of equivalent solar cell circuits, ensuring a good agreement between the experimental and theoretical curves. [ABSTRACT FROM AUTHOR]

Energy scarcity and environmental deterioration are the two main issues the world is currently experiencing. Because of their increased energy/power density and longer cycle lifetimes, pseudocapacitors have recently gained the interest of researchers in energy sector. In this study, a novel hierarchical ZnO/MnTe nanocomposite was synthesized by hydrothermal procedure for application in supercapacitors. The physical properties of the newly created electrode material were investigated using a variety of techniques. According to the outcomes of electrochemical investigations, ZnO/MnTe showed specific capacitance (Csp) of 1461 F g−1, specific energy (SE) of 54 Wh kg−1, a specific power (SP) of 267 W kg−1 at current density (Jd) of 1 A g−1, and cyclic constancy even after 5000th cycle in 2-M KOH due to combined effect of binary metals dichalcogenides. ZnO/MnTe exhibited enhanced electrochemical characteristics owing to variable oxidation state of Zn and Mn, enhanced electrical conductivity, small crystallite size, and augmented specific surface area (SSA) for storage of more charges. This study reveals the significant potential of the ZnO/MnTe electrode as a viable option for supercapacitors and other energy-conserving devices, such as capacitor and batteries. [ABSTRACT FROM AUTHOR]

Flexible solid-state supercapacitors offer intrinsic fast charging–discharging properties, facilitating the fulfillment of requirements for lightweight and multifunctional wearable electronics. In the present study, PVP/PVA/X wt% of CoMoO4 polymer nanocomposites (PNCs) have been prepared by a solution casting technique. The PNCs were characterized by different analytical tools such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM). A solid-state asymmetric supercapacitor device (ASC) is fabricated by using PVP/PVA/X wt% CoMoO4 PNCs as the positive electrode and activated carbon as the negative electrode. Electrochemical characterization of the prepared ASCs devices was performed by cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectral (EIS) analyses. The ASCs device attains a window potential of 1.5 V at chronoamperometry. At 1 A g−1 current density, PVP/PVA/1 wt% CoMoO4 ASCs device achieved specific capacitances of 11.35 F g−1. The ASCs device exhibited an outstanding cycle life with a capacitance retention of 74% after 10,000 charge/discharge cycles, a maximum energy density of 3.54 Wh kg−1, and a power density of 734 W kg−1. The EIS shows a small semicircle before and after GCD 10,000 cycles, which indicates the electrolyte has high conductivity and low internal resistance in the ASC device. It also indicates that the PVP/PVA/1 wt% CoMoO4 PNCs have potential applications as cathodic electrode for energy storage devices. [ABSTRACT FROM AUTHOR]

Photocatalysis is a multifaceted phenomenon that can be employed for diverse applications, such as waste management and the treatment of water resources. Through a hydrothermal process, a magnetic nanocomposite comprising MoS2 and NiFe2O4 with optical activity was effectively synthesized. The produced photocatalysts were subjected to different methods to investigate the physiochemical properties of the materials. The optical band-gap values of the fabricated nanocomposite were measured to be 1.75 and 1.57 eV accordingly for NiFe2O4 and MoS2/NiFe2O4 which were established by UV–Visible absorption spectrum via Tauc's relation. From the BET study, the surface area of prepared MoS2/NiFe2O4 NCs was achieved to be 71.05 m2 g−1. The photocatalytic efficacy was assessed by observing malachite green degradation in the existence of visible light conditions. The MoS2/NiFe2O4 nanocomposite contains degradation efficiency of 98.28% in 140 min under visible source toward malachite green and demonstrated favorable reusability potential through magnetic separation. This finding indicates that the activity of synthesized nanocomposite is superior to that of isolated MoS2 and NiFe2O4 NPs. A plausible mechanism for photocatalysis was explicated with charge carriers and scavengers of free radicals. The primary contributors to dye degradation were responsible to be the OH radical and holes species. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) are nanoscale renewable resources derived from lignocellulosic materials. They are known for their good optical permeability and self-assembly capability. Over the years, researchers have made great progress in developing CNC based structural color materials. However, their inherent brittleness limits their usage in applications such as optical sensors, food freshness testing, and flexible materials. To overcome these challenges, researchers have conducted extensive research to enhance the mechanical properties of CNCs, particularly their flexibility, and have achieved significant results. Creating flexible CNC based hand-shaped phase series films is a current research focus, but there are few reviews on this topic. To address this gap, the present review summarizes the primary strategies and recent research advances made in the last five years to improve the flexibility of CNC chiral phase series-type films. Furthermore, the present review provides deep insight into the various approaches to enhance the flexibility of CNCs, including polymer grafting, the introduction of small molecule additives, and co-assembly with added polymers. In addition, a detailed analysis of the advantages and disadvantages of these materials has been discussed briefly. Future research directions for developing flexible nanocellulose materials with structural color are outlined briefly. [ABSTRACT FROM AUTHOR]

Water is a vital ingredient for life, but its quality is constantly deteriorating due to textile effluent carrying harmful dyes. Photodegradation is a highly effective process for breaking down dye using solar spectrum. In the current work, hydrothermal approach was used to designed pure tungsten disulfide and doped tungsten disulfide with differnet concentration (5, 10, and 15%) for photocatalytic degradation of methylene voilet. Different instrumental analyses were conducted to measure the physichemical and optical properties of the fabricated pure and doped materials. The photocatalytic behavior of the WS2, 5% doped WS2, 10% doped WS2 and 15% doped WS2 was noted after 0, 15, 30, 45, 60, and 75 min under sunlight. The removal of methyl violet (MV) by using pristine WS2, 5% doped WS2, 10% doped WS2 was about 51, 70, and 80%, respectively. The maximum degradation of methylene violet was given by 15% doped WS2 about 90% after 75 min under sunlight. The 15% doping of the Sm reduced the band gap that can effectively absorb the greater extent of the solar spectrum and degrade the methyl violet dye. The fabricated optimized doped photocatalyst can also be employed in other application such as batteries, drug delivery, and water splitting. [ABSTRACT FROM AUTHOR]

In this study, the effects of illumination on the electronic and optoelectronic properties of Al/hydroxymethyl functionalized Zn(II)Pc/p-Si/Al photonic device have been investigated under dark and various lighting conditions. The diode's electronic parameters have been extracted from the current–voltage characteristics. It is observed that the dark current value increases when the light is illuminated on the device, and thus, the photocurrent is formed, and this result has shown that the studied device exhibits a photoconductive behavior. The photoresponse properties of the fabricated device have been examined by transient photocurrent measurements under 100 mW/cm2 illumination, and they have also been analyzed using photocapacitance and photoconductivity measurements at different frequencies (100 kHz, 500 kHz, and 1 MHz). However, the capacitance data that may occur between the poles of the produced device have also been investigated, and it is thought that the device can also be developed as a capacitor. These results confirm that the hydroxymethyl functionalized Zn(II)Pc and p-silicon semiconductor-based device can be used particularly in electro-optic and photonic applications. [ABSTRACT FROM AUTHOR]

The curcuminoid class of organic compounds is very versatile which possesses applications over vast fields of science and technology. In the present investigation, we systematically designed six curcuminoid (Crmd) derivatives with symmetric and asymmetric structures, which are named as Crmd-1 to Crmd-6. We used 2,2-difluoro-4,6-divinyl-dioxaborinine moiety as a linker to design symmetric and asymmetric donor π-conjugation and acceptor configurations. Triphenylamine and triphenylborane are used as donor and acceptors which are intrinsically donor and acceptors owing to the presence of vacant p-orbital in boron and lone pair of electrons in nitrogen atoms, respectively. Density functional theory (DFT) is applied using M06/6-311G* method to calculate linear polarizability (α), and second hyperpolarizability (γ). The value of isotropic linear polarizability (αiso) and anisotropic linear polarizability (αiso) are 125.3 × 10–24 esu and 148.1 × 10–24 esu for Crmd-6, respectively. By comparative analysis, it is observed that the highest value of γ amplitude is calculated to be 6472.3 × 10–36 esu for Crmd-6. The robust increase in non-linear optical (NLO) polarizability is observed due to the asymmetric intramolecular charge transfer (ICT) and better D-π-A configuration in Crmd-6. Time dependent DFT calculations are performed to observe the origin of third-order NLO polarizabilities. Furthermore, frontier molecular orbitals, electron density difference, molecular electrostatic potential diagrams, and transition density matrix analysis demonstrate enhanced charge redistribution from the donor to the acceptor fragments. The use of modern computational tools highlights an effective ICT, which leads stronger third-order NLO response properties in designed curcuminoid derivatives. [ABSTRACT FROM AUTHOR]

Nowadays, supercapacitors (SCs) are energy storage devices that have garnered significant consideration from researchers. However, developing supercapacitor materials utilizing a composite of transition metal oxides with high capacitive performance, structural integrity, and optimal energy proficiency while remaining cost-effective remains challenging. This work used an economically cheap and simple sol–gel method to fabricate the ZnMnO3/rGO nanohybrid composite. The structural and morphological parameters of rGO, ZnMnO3, and ZnMnO3/rGO were analyzed by FTIR, XRD, and SEM. However, the ZnMnO3/rGO exhibited the best specific capacitance (1286.879 F g−1) and energy density (85.84 Wh Kg−1) at power density (346.5 W kg−1) and showed outstanding stability after 3000th cycles. Moreover, higher electrochemical properties of the fabricated nanocomposite than individual materials are ascribed to larger surface area, smaller resistances, and faster migration of electrolyte ions. However, the fabricated nanocomposite material ZnMnO3/rGO can be employed as an electrode in storage devices, and it can also be employed in other electrochemical applications. [ABSTRACT FROM AUTHOR]

Water pollution has recently come to the forefront of people’s minds because of the widespread textile dye contamination. It suffers from a wide variety of harmful chemicals in the textile, cosmetics, food, and paint industries and these are removed by photocatalysis. Photocatalytic degradation is considered an efficient approach for the elimination of toxic pollutants from industrial effluents. In this work, MnO2/g-C3N4 nanocomposite was developed hydrothermally for photocatalytic mineralization of methylene blue (MB) dye. The surface study revealed that MnO2/g-C3N4 shows a greater surface area (97 m2 g−1) attributed to the g-CN nanosheet. The photocatalytic efficiency of MnO2, g-C3N4 & MnO2/g-C3N4 materials was additionally ascertained via the degradation of MB, which was considered to be a model dye. The MnO2, g-C3N4 & MnO2/g-C3N4 display the photocatalytic efficiency of 72.34, 85.81, and 94.32%, respectively. According to the TOC study, the MnO2/g-C3N4 nanocomposite showed a degradation rate of 71.23% over a period of 150 min. The scavenger analysis revealed that charge species (hydroxyl, hole and superoxide anion) play a substantial part in the photodegradation of dyes. The results show that the fabricated nanocomposite shows maximum photocatalytic efficacy compared to pristine material due to the appropriate bandgap along with unique structural features. The developed catalyst not only has the potential to degrade the dye and it can also work in other energy storage applications. [ABSTRACT FROM AUTHOR]

In this study, the bioelectrical power generation potential of four tropical marine microalgal strains native to Malaysia was investigated using BPV platforms. Chlorella UMACC 258 produced the highest power density (0.108 mW m−2), followed by Halamphora subtropica UMACC 370 (0.090 mW m−2), Synechococcus UMACC 371 (0.065 mW m−2) and Parachlorella UMACC 245 (0.017 mW m−2). The chlorophyll-a (chl-a) content was examined to have a linear positive relationship with the power density (p < 0.05). The photosynthetic performance of strains was studied using the pulse-amplitude modulation (PAM) fluorometer; parameters measured include the following: maximum quantum efficiency (Fv/Fm), alpha (α), maximum relative electron transport rate (rETRmax), photo-adaptive index (Ek) and non-photochemical quenching (NPQ). The Fv/Fm values of all strains, except Synechococcus UMACC 371, ranged between 0.37 and 0.50 during exponential and stationary growth phases, suggesting their general health during those periods. The low Fv/Fm value of Synechococcus UMACC 371 was possibly caused by the presence of background fluorescence from phycobilisomes or phycobiliproteins. Electrochemical studies via cyclic voltammetry (CV) suggest the presence of electrochemically active proteins on the cellular surface of strains on the carbon anode of the BPV platform, while morphological studies via field emission scanning electron microscope (FESEM) imaging verify the biocompatibility of the biofilms on the carbon anode. Key points: • Maximum power output of 0.108 mW m−2 is recorded by Chlorella UMACC 258 • There is a positive correlation between chl-a content and power output • Proven biocompatibility between biofilms and carbon anode sans exogenous mediators [ABSTRACT FROM AUTHOR]

We propose ANN-based models to analyze and extract the internal parameters of a Schottky photodiode (SPD) without presenting them with any knowledge of the highly nonlinear thermionic emission (TE) expression of the device current. We train, evaluate and demonstrate the ML models on thirty-six private datasets from three previously published devices, which denote current responses under illumination and ambient temperature of graphene oxide (GO) doped p-Si Schottky barrier diodes (SBDs). The GO doping levels are 0%, 1%, 3%, 5%, and 10%. The illumination ranged from dark (0 mW/cm2) to 30 mW/cm2. The predictions are then made completely at the intensity of 60 mW/cm2. For each diode, some values of the barrier height (ϕ ), ideality factor (n), and series resistance ( R s ) independently calculated using the Cheung–Cheung method were included in the training dataset. The predictions are done at unspecified intensities on the model development data at 80 and 100 mW/cm2, and on external data at 5% and 20% GO doping which were not part of the development dataset. The ANN achieved a mean square error and mean absolute error score below 0.003 across all datasets. This demonstrates the effective learning capabilities of the ANN models in accurately capturing the photo responses of the photodiodes and accurately predicting the internal parameters of the Schottky Barrier Diodes (SBDs), all without relying on an inherent understanding of the thermionic emission (TE) equation for SBDs. The ANN models achieved high accuracy in this process. The proposed ML models can significantly reduce analysis time in device development cycles and can be applied to other datasets in various fields. [ABSTRACT FROM AUTHOR]

The Cu2CdSnS4 (CCTS) film has been prepared using the hydrothermal approach and deposited on the p-type silicon wafer by the use of the sol–gel technique. Then, the CCTS based Al/Cu2CdSnS4 (CCTS)/p-Si/Al photodiode was produced. The prepared CCTS film was analyzed using various characterization methods such as energy-dispersive X-ray (EDX or EDS), scanning electron microscopy, and ultraviolet-visible (UV-Vis) spectroscopy. Optoelectronic and electronic attributes of the generated photodiode were investigated under the solar light and frequency conditions. The obtained data from the current measurements based on illumination intensity showed that the generated diode exhibits a photovoltaic and photoconductive behavior. In addition, it is found that the conductance and capacitance features of the diode were quite sensitive to frequency. The obtained outcomes indicated that the produced structure could be used in optoelectronic technology, especially in photodiode and solar cell applications. [ABSTRACT FROM AUTHOR]

We systematically study the optical and nonlinear optical (NLO) properties of various cyclopentadithiophene (CPDT) derivatives using quantum chemical calculations. The designed derivatives are classified into three classes and each class have three types of derivatives as a, b and c. For example, compounds 1a, 2a, and 3a are formed by substituting nitrophenyl at the terminal positions of 2,6-diphenyl-4 H-cyclopenta[2,1-b:3,4-b′]dithiophene at the terminal positions to design V-shaped (Λ-shaped) compounds and similar pattered were adopted for other classes. The dipole moment (µ), linear isotropic and anisotropic polarizability along with second-order and third-order NLO polarizability are computed by applying density functional theory (DFT) methods at PBE1PBE/6-311G** level of theory. Among all the derivatives, 3a and 1a shows the maximum linear isotropic (αiso) and anisotropic (αaniso) polarizability of 120.4 × 10−24 and 161.4 × 10−24 esu respectively. The noteworthy effect of incorporating different electron donor and acceptor moieties to the overall NLO polarizability is observed. The largest average second-order NLO polarizability value is observed 92.59 × 10−30 esu for system 1a. The β// amplitude of 1a is ~ 1.5 to 11 times more as compared to other derivatives. Additionally, the nonlinear anisotropy of β// amplitudes is also seen significantly larger ranging from 4.96 to 129.63 which is due to the V-shaped structure of designed compounds. While on the other hand, some compounds shows the third-order NLO polarizability amplitudes which are ranging in thousands including 4107 × 10−36, 5020 × 10−36, 5857 × 10−36, 6412 × 10−36, 6700 × 10−36 and 9057 × 10−36 esu for compounds 1b, 2b, 3a, 2a, 3b and 1a, respectively. Strikingly, the β// and <γ> amplitudes of compound 1a are ~ 14 and ~ 1242 times greater than that of standard para-nitroaniline (prototype NLO molecule), respectively, as computed at same PBE1PBE/6-311G** method. The TD-DFT calculations are also performed to see origin of larger NLO polarizabilities. The molecular electrostatic potential maps and frontier molecular orbitals are drawn to get further insight into the structure-NLO property relationship of newly designed CPDT derivatives. Hence, we considered that the current investigation will interest the researchers to further explore the optical and NLO applications of these CPDT derivatives. [ABSTRACT FROM AUTHOR]

1,3,4-Oxadiazole pharmacophore is still considered a viable biologically active scaffold for the synthesis of more effectual and broad-spectrum antimicrobial agents. Therefore, the present study is based on five 1,3,4-oxadiazole target structures, viz., CAROT, CAROP, CARON (D-A-D-A systems) and NOPON and BOPOB (D-A-D-A-D systems) bearing various bioactive heterocyclic moieties relevant to potential biological activities. Three of the compounds, CARON, NOPON and BOPOB were assessed in-vitro for their efficacy as antimicrobial agents against gram positive (Staphylococcus aureus and Bacillus cereus) and gram negative (Escherichia coli and Klebsiella pneumonia) bacteria; and two fungi, Aspergillus niger and Candida albicans; also, as an anti-tuberculosis agent against Mycobacterium tuberculosis. Most of the tested compounds displayed promising antimicrobial activity, especially CARON which was then analyzed for the minimum inhibitory concentration (MIC) studies. Similarly, NOPON portrayed the highest anti-TB activity among the studied compounds. Consequently, to justify the detected anti-TB activity of these compounds and to recognize the binding mode and important interactions between the compounds and the ligand binding site of the potential target, these compounds were docked into the active binding site of cytochrome P450 CYP121 enzyme of Mycobacterium tuberculosis, 3G5H. The docking results were in good agreement with the result of in-vitro studies. In addition, all the five compounds were tested for their cell viability and have been investigated for cell labeling applications. To conclude, one of the target compounds, CAROT was used for the selective recognition of cyanide ion by 'turn-off' fluorescent sensing technique. The entire sensing activity was examined by spectrofluorometric method and MALDI spectral studies. The limit of detection obtained was 0.14 µM. [ABSTRACT FROM AUTHOR]

Al/ZnO/p-Si diodes have been fabricated using different doping concentrations of a boric acid (H3BO3)-doped zinc oxide (ZnO) interlayer. The boric acid-doped ZnO films were obtained by the sol–gel method and coated by the spin-coating technique. The optoelectronic and electronic properties of the prepared diodes were studied under different illumination and frequency conditions. Current measurements of the diodes under both dark and illumination indicate that they exhibit a photovoltaic behavior. The diode with 5 wt.% H3BO3-doped ZnO interlayer showed the best diode properties with a rectification ratio of 4.23 × 104 at ± 5 V. Also, the photocurrent, photoconductance, and photocapacitance transients of the diodes prove that they exhibit both photodiode and photocapacitor behavior. In addition, the capacitance and conductance measurements of the diodes were carried out over a wide frequency range. The results denote that the generated diodes can be utilized as photo-diode/capacitors in optoelectronic technologies. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of naphthalimide Bis-Schiff bases (5a) and (5b) using a dual approach comprising computational and experimental techniques. The synthesized Bis-Schiff base compounds (5) were successfully characterized using UV–visible, fluorescence, Fourier-transform infrared (FT-IR), and 1H nuclear magnetic resonance (NMR) spectroscopies. In ethanol solvent, the experimental absorption peak was observed at 339 nm for compound 5a and at 341 and 433 nm for compound 5b. The computationally calculated absorption peak for compounds 5a was at ~ 343 nm and those for 5b were at 337 and 425 nm. The fluorescence emission bands of compounds 5a and 5b were observed at 383 and 549 nm, respectively, at an excitation wavelength of 338 nm. Additionally, quantum chemical studies of the synthesized compounds were performed to study their molecular structures linear optical and nonlinear optical (NLO) response properties. The molecular geometries were optimized to minimum energy ground state. Compounds 5a and 5b showed third-order NLO polarizability amplitudes of 391.8 × 10–36 and 489.0 × 10–36 esu, respectively, which are significantly larger than those of some standard NLO compounds. The results indicate that the Bis-Schiff base is a promising molecule for use in electronic and optoelectronic devices and biosensors. [ABSTRACT FROM AUTHOR]

The nano crystalline BaGd0.1Fe1.9O4 spinel ferrite and polypyrrole were both fabricated using sol–gel technology. The nanocomposites must be produced consisting of BaGd0.1Fe1.9O4ferrite were combined with polymer. According to the XRD analysis, the trace amounts of gadolinium ions were successfully incorporated into the spinel lattice. The crystallite size of the nanocomposites was varying from 30 to 56 nm. The nanoparticles that were embedded in the PPy matrix and acted as a block to the conduction mechanism were responsible for the increased activation energy as well as the resistivity. When placed in a magnetic field, these nanocomposites showed hysteresis loops, attesting to their ferromagnetic nature. Saturation magnetization and coercivity of nanocomposites are the two magnetic characteristics that change as the concentration of ferrite particles is increased. Ferromagnetic ferrite/polymer composites have been suggested for use in microwave absorbing applications, with PF4 compositions being considered. [ABSTRACT FROM AUTHOR]

All-optical switches have arisen great attention due to their ultrafast speed as compared with electric switches. However, the excellent optical properties and strong interaction of two-dimensional (2D) material MXene show great potentials in next-generation all-optical switching. As a solution, we propose all-optical switching used Au/MXene with switching full width at half maximum (FWHM) operating at 290 fs. Compared with pure MXene, the Au/MXene behaves outstanding performances due to local surface plasmon resonance (LSPR), including broadband differential transmission, strong near-infrared on/off ratio enhancement. Remarkably, this study enhances understanding of Au/MXene based ultrafast all-optical switching red-shifted about 34 nm in comparison to MXene, validating all optical properties of Au/MXene opening the way to the implementation of optical interconnection and optical switching. [ABSTRACT FROM AUTHOR]

The release of noxious organic pollutant from the textile industry into the water contents create a severe hazard to living and the aquatic component. The aluminate spinel family act as a potent photocatalyst to mineralize the organic dyes under the visible spectrum. But their poor photocatalytic efficiency can be enhanced with carbon-based material via composite strategies. In this study, the CoAl2O4/rGO nanocomposite is developed via the hydrothermal method. The various analytical tools employed to study the material characteristics. The photocatalytic efficiency is measured with the photomineralization of methylene blue (MB) under exposure to light of visible source. Their photocatalytic analysis suggests that CoAl2O4/rGO exhibited the 97.16% photocatalytic efficiency than a CoAl2O4 (77.51%) and rGO (88.01%). The EIS revealed that the nanohybrid exhibited 2.18 Ω than other synthesized materials. The greater photomineralization of MB is owing to the lower chances of electron (e−) and holes (h+) recombination and the large interfacial area of the rGO nanosheet. The catalytic efficacy of spinel based rGO nanohybrid can be enhanced by tuning the morphology, crystallite size and band gap. [ABSTRACT FROM AUTHOR]

The fabrication of a proficient and durable electrocatalyst for the OER process is the most crucial parameter in the water splitting process. A simple and basic procedure was used in this study to create Cu-substituted ZnMn2O4/rGO spinel nanosized composite as an electrode for OER. The morphological and structural investigations indicate that the carbon based spinel successfully bonds, and the addition of copper into rGO results in a substantial change in its electrocatalytic process for the oxygen evolution process. Zn1−xCuxMn2O4/rGO with x = 0.6 has a minimal overpotential of 150 mV at a current density of 10 mAcm−2, low onset potential of 1.40 V and a smaller Tafel slope of 31 mV dec−1 than other substitution. The electrocatalyst also exhibits high ECSA (632.5 cm2), Rf (1580), and exceptional stability, all of which improve OER performance. These analysis confirm the enhanced electrocatalytic efficiency of the hybrid material to catalyze OER for energy generation, and other fields. [ABSTRACT FROM AUTHOR]

In this paper, nonlinear optical (NLO) active single-crystal 2-amino-6-ethoxy benzothiazolium diphenylacetate (BTDPA) crystallized in an orthorhombic crystal system with non-centrosymmetric space group P212121. The thermal studies (TG–DTA and DSC) and characterization studies such as FT-IR, FT-Raman, NMR, UV–Vis–NIR, PXRD, and NLO studies (Kurtz–Perry powder method) of BTDPA crystal were recorded and investigated. Molecular geometry of BTDPA was optimized using quantum chemical computational method with M06-2X functional and 6-31G** basis set. Frontier molecular orbitals, molecular electrostatic potential, and density of states were calculated for optimized geometry to see the trend of electronic charge distributions at ground state. The TD-M06-2X method was used to calculate electronic transitions which were compared with experimental UV–Visible spectrum of BTDPA. Additionally, at molecular-level static isotropic, anisotropic linear polarizability, and third-order NLO polarizability were also calculated which were found to be 42.33 × 10–24 esu, 24.27 × 10–24 esu, and 18.95 × 10–36 esu, respectively. The current investigation of BTDPA molecule highlights good optical and nonlinear optical properties which can be of added value in the field of optoelectronic and laser applications. [ABSTRACT FROM AUTHOR]

Sensing devices are key nodes for information detection, processing, and conversion and are widely applied in different fields such as industrial production, environmental monitoring, and defense. However, increasing demand of these devices has complicated the application scenarios and diversified the detection targets thereby promoting the continuous development of sensing materials and detection methods. In recent years, Tin+1CnTx (n = 1, 2, 3) MXenes with outstanding optical, electrical, thermal, and mechanical properties have been developed as ideal candidates of sensing materials to apply in physical, chemical, and biological sensing fields. In this review, depending on optical and electrical sensing signals, we systematically summarize the application of Tin+1CnTx in nine categories of sensors such as strain, gas, and fluorescence sensors. The excellent sensing properties of Tin+1CnTx allow its further development in emerging intelligent and bionic devices, including smart flexible devices, bionic E-skin, neural network coding and learning, bionic soft robot, as well as intelligent artificial eardrum, which are all discussed briefly in this review. Finally, we present a positive outlook on the potential future challenges and perspectives of MXene-based sensors. MXenes have shown a vigorous development momentum in sensing applications and can drive the development of an increasing number of new technologies. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) during water splitting majorly based on the structure and nature of the electrocatalyst. Perovskite oxides (ABO3) have a flexible structure and range of physicochemical features that make them interesting for the present study. Therefore, scientists are interested in using electrocatalyst Perovskite oxides (ABO3) for OER. Nanostructures and amorphous patterns can appear when cations from the perovskite matrix are leached away from the A site. One of the most challenging problems is gaining enormous active amorphous subjects from cations in the B site rather than simply dissolving cations in the A site. In the present study, the crystalline perovskite (DyNiO3) has been fabricated, which is converted into an amorphous nanostructured comparative to NiO, and characterized via numerous analytical characterization methods to investigate the structural, morphological, and textural characteristics. The designed substance is then investigated for electrochemical characterizations to evaluate the overpotential, Tafel slope, and durability. Among all, DyNiO3 responses have a slight overpotential (η) of 265 mV and a low Tafel slope of 78 mV/dec with greater durability of 49 h. The efficient outcomes of the DyNiO3 are because of the grater valence state of Ni3+ containing edge splitting octahedral-frameworks, which are bordering by interstitial deformed octahedral Dy3+ ion. This research improves perovskite oxides function as catalysts and can be applied to developing enhanced OER electrocatalysts and other energy applications in the near future. Highlights: The DyNiO3 was fabricated via simple hydrothermal method. The fabricated material is characterized via numerous analytical characterization. The designed substance is then investigated for electrochemical characterizations to evaluate the overpotential, Tafel slope and durability. The DyNiO3 responses a low overpotential of 265 mV and a low Tafel slope of 78 mV/dec with greater durability of 49 h. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the protective potentials of chitosan nanoparticles (ChNPs) against silver nanoparticle (AgNP)-induced reproductive toxicity in male Wister albino rats. AgNPs, ChNPs, and AgNPs particles coated with ChNPs were characterized by using transmission electron microscope. Control rats were injected interperitoneally with 0.5% aqueous carboxymethyl cellulose. Second group was given ChNPs at a dose 300 mg/kg bwt. Third group was given AgNPs at a dose 50 mg/kg bwt. Fourth group was given AgNPs with chitosan nanoparticles simultaneously. Fifth group was given silver nanoparticles coated with chitosan nanoparticles at a dose 300 mg/kg bwt. TEM showed the formation of AgNPs with average size of 42.7 nm, ChNPs with average size of 33.3 nm, and AgNPs coated with ChNPs with average size of 48.1 nm. AgNPs significantly reduced serum levels of FSH, LH, testosterone and prolactin, sperm count, morphology index, vitality, total motility and progressive motility, the activities of catalase and superoxide dismutase, and the concentration of reduced glutathione in testicular tissues. However, it significantly increased malondialdehyde concentration in testicular tissues, sperm abnormalities, testicular tissue damages, non-progressive motility, and immotile sperms. On the contrast, ChNPs ameliorated AgNP-induced alteration in serum levels of sex hormones, spermogram, and testicular tissue's structure and functions. These results indicated that ChNPs had protective potential against AgNP-induced reproductive toxicity and ChNPs coating AgNPs had more potent protective effect than ChNPs administrated together with AgNPs. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Electrical characterization of silicon PV-cell: modeling" published in Applied Physics A: Materials Science & Processing. The correction addresses errors in Figures 6a and 7 of the original article, where incorrect minus signs were included in "z'". The corrected figures are provided in the notice. The original article has been updated to reflect these corrections. The publisher, Springer Nature, maintains a neutral stance on jurisdictional claims and institutional affiliations. The authors of the article are Nejmeddine Yahyaoui, Salaheddine Mansouri, Abdullah G. Al-Sehemi, A. Dere, A. Al-Ghamdi, and Fahrettin Yakuphanoglu. [Extracted from the article]

Highlights: A robust technique-methodology of electrochemical CRISPR sensing is first proposed for the rapid, highly sensitive and specific detection of SARS-CoV-2 variant without any nucleic-acid-amplification assays. Using the DNA template identical to SARS-CoV-2 Delta spike gene sequence as model, our biosensor exhibited excellent analytical detection limit (50 fM) and high linearity (R2 = 0.987) without any amplification assay. Specific crRNA was designed to match the mutation site on nucleic acid sequence of the SARS-CoV-2 Delta variant, presenting programmability, universality, and scalability for diagnosis of other emerging SARS-CoV-2 variants.Coronavirus disease 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The gold standard method for the diagnosis of SARS-CoV-2 depends on quantitative reverse transcription-polymerase chain reaction till now, which is time-consuming and requires expensive instrumentation, and the confirmation of variants relies on further sequencing techniques. Herein, we first proposed a robust technique-methodology of electrochemical CRISPR sensing with the advantages of rapid, highly sensitivity and specificity for the detection of SARS-CoV-2 variant. To enhance the sensing capability, gold electrodes are uniformly decorated with electro-deposited gold nanoparticles. Using DNA template identical to SARS-CoV-2 Delta spike gene sequence as model, our biosensor exhibits excellent analytical detection limit (50 fM) and high linearity (R2 = 0.987) over six orders of magnitude dynamic range from 100 fM to 10 nM without any nucleic-acid-amplification assays. The detection can be completed within 1 h with high stability and specificity which benefits from the CRISPR-Cas system. Furthermore, based on the wireless micro-electrochemical platform, the proposed biosensor reveals promising application ability in point-of-care testing. [ABSTRACT FROM AUTHOR]

In this article, a new Schottky diode based on a transparent conducting polymer 2-(4-fluorophenyl)-2-oxoethyl-2-methylprop-2-enoate (PFPAMA) that is doped up to 5% with ZnO is presented. PFPAMA is a promising transparent polymer that is inclined towards n-type behavior with the potential to be used as an electron transport layer. Each device had the Al/p-Si:(PFPAMA:ZnO)/Al structure. The diode ideality factor was found to depend on bias and illumination but the calculated interface state density is lower by 3 orders of magnitude than for most reported Al/p-Si diodes, suggesting that the presence of the polymer suppresses interface states. The measured electrical and photoresponse characteristics confirm that the resulting diodes are suitable for fast photodiodes over the intensity range of dark to 100 mW/cm2 whose performance can be optimized by ZnO doping. The application of functionalized polymers on p-silicon for sensing applications is an emerging field. [ABSTRACT FROM AUTHOR]

The world is now facing intolerable damage in all sectors of life because of the deadly COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2. The discovery and development of anti-SARS-CoV-2 drugs have become pragmatic in the time needed to fight against this pandemic. The non-structural protein 3 is essential for the replication of transcriptase complex (RTC) and may be regarded as a possible target against SARS-CoV-2. Here, we have used a comprehensive in silico technique to find potent drug molecules against the NSP3 receptor of SARS-CoV-2. Virtual screening of 150 Isatin derivatives taken from PubChem was performed based on their binding affinity estimated by docking simulations, resulting in the selection of 46 ligands having binding energy greater than −7.1 kcal/mol. Moreover, the molecular interactions of the nine best-docked ligands having a binding energy of ≥ −8.5 kcal/mol were analyzed. The molecular interactions showed that the three ligands (S5, S16, and S42) were stabilized by forming hydrogen bonds and other significant interactions. Molecular dynamic simulations were performed to mimic an in vitro protein-like aqueous environment and to check the stability of the best three ligands and NSP3 complexes in an aqueous environment. The binding energy of the S5, S16, and S42 systems obtained from the molecular mechanics Poisson–Boltzmann surface area also favor the system's stability. The MD and MM/PBSA results explore that S5, S16, and S42 are more stable and can be considered more potent drug candidates against COVID-19 disease. [ABSTRACT FROM AUTHOR]

Smart nanofibers have been used to create sensing tools for various purposes, such as anticounterfeiting. However, electrospinning produces nanofibers at a low yield, high cost, and requires high voltage. The recently invested solution blowing spinning method generates nanofibers at low cost and high yield without the need for high voltage. Moreover, the efficiency of nanofibrous coatings has been enhanced and strengthened by cellulose nanowhiskers (CNWs). Fluorescent photochromism is an interesting technique for the preparation of dual-mode security encoding authentication materials. Herein, novel photochromic emissive nanofibrous films composed of CNW-supported polyacrylonitrile (PAN) nanocomposite incorporated with alkaline earth activated aluminate nanoparticles (AEAN) was prepared to present security authentication films with optical photo-responsiveness for anticounterfeiting applications. To create a colorless film, AEAN and CNW must be well-dispersed in the PAN-based composite. Nanofiber-coated paper sheets were analyzed by luminescence spectra to display a green emission at 527 nm. The photochromic nanofiber-coated sheets demonstrated strong reversibility under UV and daylight. The current advance can be reported as an efficient strategy to manufacture authenticated merchandise. [ABSTRACT FROM AUTHOR]

The possibility of tuning the chemical structures of oligothiophenes offers various applications in designing of optoelectronics and nonlinear optical (NLO) materials. In the current study, we report a computational study of quinoidal oligothiophenes to explore the influence of type of π-conjugation chains and nature of terminal acceptor groups to push their linear (α) and third-order nonlinear optical (γ) polarizability to a robust limit. The ground-state molecular geometries of designed compounds 1–8 are optimized using DFT at the M06/6-311G** level of theory. Among all the designed compounds, the largest linear isotropic (αiso) and anisotropic (αaniso) polarizability values of 342.7 × 10–36 and 765.6 × 10–36 esu are shown by compound 8 owing to its excellent electronic connection between central thiophene rings and terminal acceptor groups. Similarly, the highest average static third-order nonlinear optical (NLO) polarizability < γ > amplitude of 7448 × 10–36 esu is shown by compound 8 which is ~ 1319, ~ 103, ~ 21, ~ 77, ~ 40, ~ 28, and ~ 13 times greater as compared to compounds 1–7, respectively. Strikingly, comparative analysis of < γ > between compound 8 and p-NA (prototype NLO molecule) reveals that < γ > amplitude of compound 8 is 1021 times more than that of p-NA at the same M06/6-311G** methodology as calculated in current investigation. Remarkably, the large difference between < γ > values of compound 8 and p-NA designates significant potential of our designed compound for various NLO applications. Furthermore, TD-DFT computations indicate that the greater NLO response of compound 8 is because of its higher oscillator strength and lower transition energy in contrast to other designed molecular systems. Moreover, TD-DFT calculations are also used to investigate structure-NLO property relations in terms of frontier molecular orbitals (FMOs), the density of states (DOS), molecular electrostatic potential (MEP), and transition density matrix (TDM) parameters. We believe the current design will instigate the materials science community for such novel motifs with efficient optoelectronic and NLO properties. [ABSTRACT FROM AUTHOR]

COVID-19 is a serious respiratory infection caused by a beta-coronavirus that is closely linked to SARS. Hypoxemia is a symptom of infection, which is accompanied by acute respiratory distress syndrome (ARDS). Augmenting supplementary oxygen may not always improve oxygen saturation; reversing hypoxemia in COVID-19 necessitates sophisticated means to promote oxygen transfer from alveoli to blood. Inhaled nitric oxide (iNO) has been shown to inhibit the multiplication of the respiratory coronavirus, a property that distinguishes it from other vasodilators. These findings imply that NO may have a crucial role in the therapy of COVID-19, indicating research into optimal methods to restore pulmonary physiology. According to clinical and experimental data, NO is a selective vasodilator proven to restore oxygenation by helping to normalize shunts and ventilation/perfusion mismatches. This study examines the role of NO in COVID-19 in terms of its specific physiological and biochemical properties, as well as the possibility of using inhaled NO as a standard therapy. We have also discussed how NO could be used to prevent and cure COVID-19, in addition to the limitations of NO. [ABSTRACT FROM AUTHOR]

In the present investigation, a variety of quinoidal oligomers with different arrangements and distinctive fused shapes of thiophene rings are studied. These quinoidal oligomers were further explored for the systematic heteroatom substitution using state-of-art quantum computational methods. The substitution of S atoms by O and N in oligomer compounds is done to see change in optical and nonlinear optical properties while moving from series 1 to series 4. The substitution of oligomer chain shows a significant effect on linear polarizability, first and second hyperpolarizabilities as calculated at M06/6-311G** level of theory. All the studied compounds showed relatively average first hyperpolarizability while reasonably large second hyperpolarizability. Among all the studied compounds, the largest second hyperpolarizability of 1003 × 10–36 esu is shown by 4c which is ~ 138 times greater than standard p-NA molecule. Interestingly, TD-DFT analysis indicates that the series 4 has larger oscillator strengths and lower transition energy values which contributes to its enlarged amplitude of second hyperpolarizability response. Furthermore, the transition density matrix, frontier molecular orbitals and molecular electrostatic potential diagrams showed that the charge transfer occurs from oligomer chain to cyanide groups and this charge transfer is highly dependent on the substitution patterns. The density of states diagrams of the selected class of compounds 4a, 4b and 4c show that 4c has significant partial contributions of oligomer chain in HOMO–LUMO orbitals. Thus, the comparative study of four series of compounds indicates not only the importance of shape and size of oligomer molecules but also indicates the importance of heteroatom substitutions to attain a vigorous second hyperpolarizability response for their potential use in optoelectronic and NLO applications. [ABSTRACT FROM AUTHOR]

The current study reveals the inhibitory potential of novel bioactive compounds of mangrove actinomycetes against nsp10 of SARS-CoV-2. A total of fifty (50) novel bioactive (antibacterial, antitumor, antiviral, antioxidant, and anti-inflammatory) compounds of mangrove actinomycetes from different chemical classes such as alkaloids, dilactones, sesquiterpenes, macrolides, and benzene derivatives are used for interaction analysis against nsp10 of SARS-CoV-2. The six antiviral agents sespenine, xiamycin c, xiamycin d, xiamycin e, xiamycin methyl ester, and xiamycin A (obeyed RO5 rule) are selected based on higher binding energy, low inhibition constant values, and better-docked positions. The effective hydrogen and hydrophobic (alkyl, π –sigma, π – π T shaped and π -alkyl) interaction analysis reveals the four antivirals sespenine, xiamycin C, xiamycin methyl ester, and xiamycin A are supposed to be the most auspicious inhibitors against nsp10 of SARS-CoV-2. Quantum chemistry methods such as frontier molecular orbitals and molecular electrostatic potential are used to explain the thermal stability and chemical reactivity of ligands. The toxicity profile shows that selected ligands are safe by absorption, distribution, metabolism, excretion, and toxicity profiling and also effective for inhibition of nsp10 protein of SARS-CoV-2. The molecular dynamic simulation investigation of apo and halo forms of nsp10 done by RMSD of C α atoms of nsp10, all amino acid residues RMSF, count total number of hydrogen bonds and radius of gyration (Rg). MD simulations reveal the complexes are stable and increase the structural compactness of nsp10 in the binding pocket. The lead antiviral compounds sespenine, xiamycin C, xiamycin methyl ester, and xiamycin A are recommended as the most promising inhibitors against nsp10 of SARS-CoV-2 pathogenicity. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) cobalt molybdate (CoMoO4) hierarchical nanoflake arrays on pencil graphite electrode (PGE) (CoMoO4/PGE) are actualized via one-pot hydrothermal technique. The morphological features comprehend that the CoMoO4 nanoflake arrays expose the 3D, open, porous, and interconnected network architectures on PGE. The formation and growth mechanisms of CoMoO4 nanostructures on PGE are supported with different structural and morphological characterizations. The constructed CoMoO4/PGE is operated as an electrocatalytic probe in enzyme-less electrochemical glucose sensor (ELEGS), confronting the impairments of cost- and time-obsessed conventional electrode polishing and catalyst amendment progressions and obliged the employment of a non-conducting binder. The wide-opened interior and exterior architectures of CoMoO4 nanoflake arrays escalate the glucose utilization efficacy, whilst the intertwined nanoflakes and graphitic carbon layers, respectively, of CoMoO4 and PGE articulate the continual electron mobility and catalytically active channels of CoMoO4/PGE. It jointly escalates the ELEGS concerts of CoMoO4/PGE including high sensitivity (1613 μA mM−1 cm−2), wide linear glucose range (0.0003–10 mM), and low detection limit (0.12 µM) at a working potential of 0.65 V (vs. Ag/AgCl) together with the good recovery in human serum. Thus, the fabricated CoMoO4/PGE extends exclusive virtues of modest electrode production, virtuous affinity, swift response, and excellent sensitivity and selectivity, exposing innovative prospects to reconnoitring the economically viable ELEGSs with binder-free, affordable cost, and expansible 3D electrocatalytic probes. [ABSTRACT FROM AUTHOR]

Well-defined NiSe@ZnSe composite electrode was synthesized along with polyvinyl pyrrolidone (PVP) and sodium lauryl sulfate (SLS) surfactant whose redox behavior is an interesting approach toward boosting performance of the supercapacitor. High crystallinity suggested that prepared composite NiSe@ZnSe was well appropriate for the application concerning the supercapacitor electrode material. The Raman spectroscopy identified the functional group, vibrations, stretching of bonds, and presence of defects in the samples. The surface to volume ratio of the loosely packed grass-like structures resulted in availability of more surface area for the electrolyte which leads to the enhanced reaction rates. As-prepared active synthesized product revealed 442 Fg−1 specific capacitance at 1 Ag−1 with 99.3% high-rate capability at 10 Ag−1 after 2000 cycles. Besides, notably, capacity retention of the sandwiched asymmetric NiSe@ZnSe//AC device was maintained to be 99.48% after constant charge−discharge 2000 cycles and displayed outstanding electrochemical stability. Herein, NiSe@ZnSe composite electrode was prepared because Zn could improve the electrical conductivity and capacitive performance. Ni can improve active site density and conductivity. Meanwhile, selenium enhanced charge transfer properties. Therefore, binary composite NiSe@ZnSe acts as a satisfactory electrode material for energy saving application. [ABSTRACT FROM AUTHOR]

Over the last few decades, the global prevalence of neurodevelopmental and neurodegenerative illnesses has risen rapidly. Although the aetiology remains unclear, evidence is mounting that exposure to persistent hydrocarbon pollutants is a substantial risk factor, predisposing a person to neurological diseases later in life. Epidemiological studies correlate environmental hydrocarbon exposure to brain disorders including neuropathies, cognitive, motor and sensory impairments; neurodevelopmental disorders like autism spectrum disorder (ASD); and neurodegenerative disorders like Alzheimer's disease (AD) and Parkinson's disease (PD). Particulate matter, benzene, toluene, ethylbenzene, xylenes, polycyclic aromatic hydrocarbons and endocrine-disrupting chemicals have all been linked to neurodevelopmental problems in all class of people. There is mounting evidence that supports the prevalence of petroleum hydrocarbon becoming neurotoxic and being involved in the pathogenesis of AD and PD. More study is needed to fully comprehend the scope of these problems in the context of unconventional oil and natural gas. This review summarises in vitro, animal and epidemiological research on the genesis of neurodegenerative disorders, highlighting evidence that supports inexorable role of hazardous hydrocarbon exposure in the pathophysiology of AD and PD. In this review, we offer a summary of the existing evidence gathered through a Medline literature search of systematic reviews and meta-analyses of the most important epidemiological studies published so far. [ABSTRACT FROM AUTHOR]

The present investigation highlights the two-dimensional design of several interesting superalkali-doped borophene derivatives for efficient nonlinear optics (NLO). The combination effects and resulting NLO responses of borophene (B36) and superalkali units (Li3O) were evaluated by orienting superalkali clusters at various sites, such as the hub, rim, and bridge, around an B36 molecule. The charge analysis was characterized by frontier and natural bond orbital analyses, a narrowed HOMO–LUMO bandgap and greater intramolecular charge transfers. Molecular electrostatic potential surfaces demonstrated enhanced optoelectronic features of these complexes that are viable due to Li3O adsorption. Singly doped and doubly doped complexes were considered, and their NLO properties were calculated. Bandgap energy was reduced approximately threefold when doped with two Li3O. As a considerably high figure of merit, first hyperpolarizability (βo) values of up to five digits (including 10,611 au for complex A) prove that these systems can be utilized as promising candidates in various NLO applications. [ABSTRACT FROM AUTHOR]

Co–Fe bimetallic nanoparticles-affixed polyvinylidene fluoride-co-hexafluoropropylene (PVdF-HFP) nanofiber membrane is fabricated using the electrospinning and chemical reduction techniques. The semicrystalline polymeric backbone decorated with the highly crystalline Co–Fe bimetallic nanoparticles enunciates the mechanical integrity, while the incessant and swift electron mobility is articulated with the consistent dissemination of bimetallic nanoparticles on the intersected and multi-layered polymeric nanofibers. The diffusion and adsorption of glucose are expedited in the extended cavities and porosities of as-formulated polymeric nanofibers, maximizing the glucose utilization efficacy, while the uniformly implanted Co4+/Fe3+ active centers on PVdF-HFP nanofibers maximize the electrocatalytic activity toward glucose oxidation under alkaline regimes. Thus, the combinative sorts including nanofiber and nanocomposite strategies of PVdF-HFP/Co–Fe membrane assimilate the enzyme-less electrochemical glucose detection concerts of high sensitivity (375.01 μA mM−1 cm−2), low limit of detection (0.65 μm), and wide linear range (0.001 to 8 mM), outfitting the erstwhile enzyme-less glucose detection reports. Additionally, the endowments of high selectivity and real sample glucose-sensing analyses of PVdF-HFP/Co–Fe along with the binder-less and free-standing characteristics construct the state-of-the-art paradigm for the evolution of affordable enzyme-less electrochemical glucose sensors. [ABSTRACT FROM AUTHOR]

This study employed a bottom-up technique to synthesize copper oxide (CuO) nanoparticles over hydrophilic graphene oxide (GO) nanosheets. The CuO/GO nanocomposite has been prepared using two selected precursors of copper nitrate and citric acid with an intermittent mixing of GO solutions. The synthesized Nanocomposites were characterized using different biophysical techniques like FT-IR, NMR, FE-SEM, and HR-TEM analyses. FT-IR analyses confirm the nanocomposites' successful formation, which is evident from the functional groups of C=C, C-O, and Cu-C stretching vibrations. Morphological analyses reveal the depositions of CuO nanoparticles over the planar rough GO sheets, which has been elucidated from the FE-SEM and HR-TEM analyses supported by respective EDAX analyses. The antimicrobial activities have been evident from the surface roughness and damages seen from the FE-SEM analyses. The CuO/GO sheets were tested against Gram-positive (e.g., Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa). It is evident that the intrinsic antibacterial activity of CuO/GO sheets, when combined in equal proportions, elicited a robust antibacterial activity when tested over Gram –ve representative bacteria Escherichia coli. The antioxidant behaviour of synthesized CuO/GO nanocomposite was evaluated by scavenging the free radicals of DPPH and ABTS. Moreover, the cytotoxic activity was also studied against epidermoid carcinoma cell line A-431. A brief mathematical formulation has been proposed in this study to uncover the possibilities of using the nanocomposites as potential drug candidates in theranostic applications in disease treatment and diagnosis. This study would help uncover the electronic properties that play in the nano-scaled system at the material-bio interface, which would aid in designing a sensitive nano-electromechanical device bearing both the therapeutic and diagnostic attributes heralding a new horizon in the health care systems. A bottom-up technique has been employed to synthesize copper oxide (CuO) nanoparticles over hydrophilic graphene oxide (GO) nanosheets. The synthesized CuO/GO nanocomposites exhibited potential antibacterial (human pathogens), antioxidant (DPPH & ABTS) and anticancer (epidermoid carcinoma A-431) activity. This study would help uncover the electronic properties that play in the nano-scaled system at the material-bio interface, which would aid in designing a sensitive nano-electromechanical device bearing both the therapeutic and diagnostic attributes heralding a new horizon in the health care systems. Highlights: The CuO/GO nanocomposite has been prepared using two selected precursors of copper nitrate and citric acid with an intermittent mixing of GO solutions. CuO nanoparticles decoration on GO sheets to coincide the enrichment of activity and stability from their cooperation. CuO/GO nanocomposite has appreciable activity towards pathogenic bacteria, free radicals, and cancer cell lines. The as-prepared nanocomposite is proposed as a novel nanomaterial for theranostic activities bearing both therapeutic attributes along with diagnostic nature in the biological domain and healthcare. [ABSTRACT FROM AUTHOR]

Nickel iron oxides with different molar ratios were successfully prepared by facile hydrothermal method. Prepared NiFeO, with ratios of Ni:Fe as [3:1], [1:1] and [1:3], samples are further analyzed by basic characterizations like X-ray diffraction, UV–Vis absorption photoluminescence and FT-IR spectra investigations. The bandgap of the NiFeO [3:1], NiFeO [1:1] and NiFeO [1:3] samples were calculated to be 2.96 eV, 2.74 eV and 2.22 eV correspondingly. The morphology exhibited by the NiFeO [3:1], NiFeO [1:1] samples is the combined nanoparticles and nanosheets with thick and thin layers. The reduced in size explored Fe ions incorporation and NiFeO [1:3] sample revealed small nanoparticles. The electrochemical activity was studied. CV, LSV, EIS and CA spectra were analyzed. The specific capacitance of NiFeO [3:1], NiFeO [1:1] and NiFeO [1:3] is 232, 264 and 290 F/g. The overpotential calculated is 240 mV, 200 mV and 174 mV @ 10 mA/ cm2 for NiFeO [3:1], NiFeO [1:1] and NiFeO [1:3] with 232 mA/g, 320 mA/g and 352 mA/g current densities. Lower overpotential of NiFeO [1:3] helped to attain higher current density which gives the smaller resistance. This unique behavior is enhanced by addition of Fe ions in higher concentration. The NiFeO [1:3] electrocatalysts were subjected to run for 12 h and there is no decrease in its performance. The better morphology and higher active sites enabled by indulging of Fe ions in NiFeO [1:3] electrode will be the best candidate for upcoming future use with no deduction in its performance. [ABSTRACT FROM AUTHOR]

The conversion of insulating polymeric membrane into conducting activated carbon nanofiber (ACF) membrane and the decoration of consequent fibers with flower-like CuO/NiO nanoarchitectures are accomplished, respectively, via the carbonization and electrodeposition processes. The glucose utilization efficacy of CuO/NiO/ACF is accelerated through the diffusion and adsorption of analyte into the nanofibers' voids and stacked layers, respectively, of ACF and flower-like architectures. The conducting carbon web, binary metal oxide synergism, and porous architecture of CuO/NiO/ACF proliferate the considerable sensitivity (247 µA mM−1 cm−2), low sensing limit (146 nM), and wide linear range (0.00025–5 mM) on glucose sensing along with the real sample analysis. The concordant electrochemical glucose oxidation behavior realized at different bending angles exposes the flexibility of CuO/NiO/ACF. Thus, the free-standing, flexible, binder-less, recyclable, and cost-and time-effective features of CuO/NiO/ACF convenience the glucose detection, affording an innovative technological platform for the evolution of high performance and durable glucose sensors. [ABSTRACT FROM AUTHOR]