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This review presents a comprehensive analysis of the recent formulation of nanoparticle-reinforced solder alloys, focusing on their main properties and improvements in mechanical performance. The introduction provides an overview of solder alloys and the concept of formulating nanoparticle-reinforced solder alloys. The discussion systematically reviews the importance of various properties and critically evaluates the findings from the literature. The review compares and synthesizes the outcomes and insights regarding the impact of nanoparticle addition on the properties and performance of the resulting composite solder alloys. The aim is to identify recent trends, scientific challenges, limitations, and potential breakthroughs in the current formulation of nanoparticle-reinforced solder alloys. The key value of this review lies in the compilation of the latest reports and technical setups, along with the authors' critical analysis and perceptions. This review provides an in-depth understanding and guidance for formulating novel and high-performance nanoparticle-reinforced solder alloys, making it a valuable resource for researchers and engineers in the field of advanced soldering materials.

Thin films are the backbone of the electronics industry, and their widespread application in heat sensors, solar cells, and thin-film transistors has attracted the attention of researchers. The current study involves the deposition of a hetero-structured (ZnO/Zn/ZnO) thin film on a well-cleaned glass substrate using the DC magnetron sputtering technique. The samples were then annealed at 100, 200, 300, 400, and 500 °C. The structural, morphological, and electrical characteristics of the annealed samples as well as one as-deposited sample were then examined using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and a Hall effect measuring apparatus. XRD analysis showed a hexagonal ZnO crystal structure for the samples annealed at 300 and 400 °C, whereas the samples annealed at 100 and 200 °C showed metallic zinc and hexagonal ZnO, and the crystallinity decreased for the sample annealed at 500 °C with pure hexagonal crystal symmetry. According to the AFM study, as the annealing temperature increases, the average roughness (Ra) decreases. Temperature has an inverse relationship with particle size. The optimal annealing temperature was determined to be 400 °C. Over this temperature range, the average roughness and particle size increased. Similarly, when Ra decreased, the conductivity increased and the resistance decreased. A fundamental difficulty is that the heating of the heterostructure to 400 °C melts the Zn-based intermediate layer, which alters the Zn phase and disrupts the sample homogeneity.

This research paper delves into the optoelectronic and thermoelectric properties of the quaternary layered selenide compound CsZrCuSe3, employing a comprehensive computational approach based on density functional theory (DFT) with the HSE06 functional and Boltzmann transport theory. CsZrCuSe3 is a quaternary chalcogenide compound with a tunable bandgap, making it a promising candidate for optoelectronic applications such as photodetectors, solar cells, and LEDs. The electronic properties of CsZrCuSe3 were investigated, revealing a direct bandgap of 1.32 eV at the Γ point. The optical properties, including the dielectric constant and optical conductivity, were analyzed, demonstrating strong absorption in the violet-blue range. Furthermore, the paper explores the thermoelectric properties of CsZrCuSe3, including the Seebeck coefficient, electrical conductivity, thermal conductivity, and the figure of merit (ZT). These properties exhibit intriguing behavior dependent on temperature and chemical potential, with an anomaly observed in the Seebeck coefficient at specific chemical potentials. This anomaly presents an opportunity to gain insights into the complex interplay of electronic properties in semiconductor materials, potentially leading to advancements in thermoelectric applications. Further research and collaboration are essential to decipher the underlying mechanisms and optimize the material for practical use in various technological applications.

Tin oxide (SnO2) materials were prepared via successive ionic layer adsorption and reaction (SILAR) technique at varying deposition times. The synthesized tin oxide layer served as an electron transport layer for the deposition of a perovskite layer via spin coating method. The morphology, structure, elemental, optical features and vibration modes of the prepared samples have been studied using scanning electron microscopy (SEM), X-ray diffractometry (XRD), energy dispersive X-ray spectroscopy (EDX), UV–vis spectrophotometry, and Raman spectrophotometry, respectively. The films revealed granular-shaped nanograins with a maximum average grain size of 197.03 nm. XRD results showed a cassiterite pure-phase crystal structure with several prominent peaks. EDX studies confirmed the as-deposited elemental constituents with good optical properties obtained from the optical studies. The band gap energies ranged from 4.01 to 4.24 eV at increasing deposition times. The phonon modes and crystal structures were also revealed from the Raman studies. The materials find applications in solar cells and electronic devices.

Currently, the global energy consumption is extensively increasing at a pace faster than the source advancement. The demand for renewable energy generation is an important scheme to settle energy crisis and climate changes which are prominent challenges facing the modern society. Therefore, fabrication of efficient energy storage and conversion technologies have been emerged as a prospective research topic to achieve a convenient utilization of clean energy. In particular, supercapacitors are among the most effective and practically feasible energy storage devices. They offer several characteristic attributes, including fast charging rates, high power densities, extended durability, and convenient setup. Supercapacitor plays an important role as a clean energy device to link conventional capacitors with batteries. This review concentrates on the most recent progress on phosphate-based electroactive materials for supercapacitor application. Phosphate based materials have received curious attention as electrode material for supercapacitors due to their abundance, non-toxicity, and other admirable electrochemical properties. This review presents the recent progress on practical application of phosphate based materials in supercapacitors. The key performance metrics such as power and energy density, capacitance, and cyclic stability of several phosphate based supercapacitor devices have been summarized. Finally, the review present conclusive and future perspectives on the study area.

Bi(2-x)TixO3 (x = 0, 0.01, 0.03. & 0.05) (BO-xT) ceramics are prepared by conventional solid-state route followed by low sintering temperatures. X-ray diffraction analyses show the presence of the monoclinic phase of Bi2O3. The electrical conductivities at room temperature concerning the frequency (ranging from 25 kHz to 5 MHz) and Seebeck Coefficient ranging from 50°C to 400°C were measured. With an increase in Ti (dopant) content, the conductivity and Seebeck Coefficient increased with the temperature increment. The BO-0.03T has the highest Seebeck value (47 μV/°C), which shows a higher carrier concentration. In terms of electrical conductivities, the BO-0.05T ceramic shows the maximum electrical conductivity, i.e. 2.0 × 10−9 μS/m as compared to other samples, which exhibit the presence of free electrons. Moreover, relative permittivity (dielectric constant) and dielectric loss are also measured concerning the frequency at room temperature to investigate the dielectric behaviour of the ceramics. This low-temperature sintering ceramics will open new applications in the domain of electronic materials.

Although, zinc oxide nanoparticles (ZRTs) as an anti-cancer agent have been the subject of numerous studies, none of the reports has investigated the impact of the reaction entry time of ion-carriers on the preparation of ZRTs. Therefore, we synthesized variants of ZRTs by extending the entry time of NaOH (that acts as a carrier of hydroxyl ions) in the reaction mixture. The anti-proliferative action, morphological changes, reactive oxygen species (ROS) production, and nuclear apoptosis of ZRTs on human A431 skin carcinoma cells were observed. The samples revealed crystallinity and purity by X-ray diffraction (XRD). Scanning electron microscopy (SEM) images of ZRT-1 (5 min ion carrier entry) and ZRT-2 (10 min ion carrier entry) revealed microtubule like morphology. On prolonging the entry time for ion carrier (NaOH) introduction in the reaction mixture, a relative ascent in the aspect ratio was seen. The typical ZnO band with a slight shift in the absorption maxima was evident with UV-visible spectroscopy. Both ZRT-1 and ZRT-2 exhibited non-toxic behavior as evident by RBC lysis assay. Additionally, ZRT-2 showed better anti-cancer potential against A431 cells as seen by MTT assay, ROS generation and chromatin condensation analyses. At 25 μM of ZRT-2, 5.56% cells were viable in MTT test, ROS production was enhanced to 166.71%, while 33.0% of apoptotic cells were observed. The IC50 for ZRT-2 was slightly lower (6 μM) than that for ZRT-1 (8 μM) against A431 cells. In conclusion, this paper presents a modest, economical procedure to generate ZRT nano-structures exhibiting strong cytotoxicity against the A431 cell line, indicating that ZRTs may have application in combating cancer.

In this work, a simple sensitive validated liquid chromatography mass spectroscopy (LC-MS/MS) analytical method was developed for the determination of Spirodiclofen residues in different aquatic toxic media. The toxic media were those that provide nutrients and help with the growth of different aquatic organisms for their survival and multiplication. The different media were the M4 medium for Daphnia magna and The Organization for Economic Cooperation and Development (OECD TG 201) medium for alga. Fe2O3-Ag2O/TiO2 nanocomposites were prepared by using a precipitation method, which was used as a photo-catalyst for the removal of Spirodiclofen pesticide from aquatic media. The experiment was performed under direct sunlight at a single fortification level (1.0 µg/mL) in M4 and OECD TG 201 media. The optimum catalyst concentration for the complete degradation was found to be 10 mg/L under sunlight. Spirodiclofen residues in water were determined by LC-MS/MS, and the rate constant DT50 (half-life) values were calculated from the obtained data. The results showed that with Fe2O3-Ag2O/TiO2 nanocatalyst, the DT50 (half-life) value was found to be approximately 8 h. These results revealed that iron-oxide- and silver-oxide-incorporated TiO2 nanocomposites were excellent photocatalysts when compared with TiO2, Fe2O3-TiO2, and Ag2O-TiO2 for the decontamination of pesticide residues in aquatic media samples.

Micro- and meso-porous structures of alumina have attracted attention for their potential use in different applications. In this research, a novel and facile route was introduced for dual growth of alumina nanoparticles and carbon nanotubes together to fabricate nanocomposites at low temperature 250 °C through explosive processes of solid fuel. In this trend, series of alumina species with and without carbon nanotubes were prepared and characterized by X-ray diffraction, Raman spectra and transmission electron microscopy.The surface properties of the alumina-CNT nanocomposites were characterized and compared with the prepared nanoparticles of alumina by adsorption–desorption system. The specific surface area of the prepared alumina-CNT nanocomposites was increased from 257.9 to 307.7 m2/g and 314.8 m2/g with growing CNTs inside the porous structure of alumina. These increments were observed because of the dual growth of nanoparticles and nanotubes by which new micropores inside their nanocomposites were created. When the source of CNTs was changed from ethanol to methanol, pure mesoporous structure with narrow pore size distribution was observed for the alumina-CNT nanocomposite. In addition, the surface area and the total pore volume increased to be 324.9 m2/g and 0.673 cm3/g; respectively.The detonation technique of an explosive solid has been used for the first time to improve and control the porous structure of alumina through dual growth of CNTs and alumina at low temperature to meet the special requirements of the markets of catalysis and water purification. Keywords: Microporous structure, Mesoporous structure, Alumina texture control, CNT-alumina dual growth at low temperature, Detonation of explosive solids

The precipitation process was applied to synthesize chitosan-coated zinc oxide nanoparticles (chitosan-ZnO NPs). Then, various characterization tools were used such as XDR, SEM, TEM, FTIR, and EDX. The use of these 50 nm chitosan-ZnO NPs in soil decontamination of thifluzamide and difenoconazole pesticide residues is being investigated. In two distinct soils, the effect of catalytic decontamination on pesticide residues was examined (sandy loam and sandy clay soils). The studies required two sets of pesticide concentrations. One set of samples was added to the chitosan-ZnO NPs catalyst, and the other set was studied without the addition of a catalyst. Photocatalytic studies were conducted under the sunlight in July. The soil samples were hand-spread in a glass dish to a height of 5 mm and sprayed with an aqueous solution of pesticide. From 8 a.m. to 5 p.m., these samples were exposed to sunlight in October 2021. We found that the best concentration of catalyst was 0.05%. The acquired samples were quantified using validated Ultra-Fast Liquid Chromatography (UFLC) with Photo Diode Array (PDA) detection. Kinetic parameters such as rate constant k and the degradation rate of pesticides DT50 have been calculated using Pesticide Residue Dissipation Data. The findings showed that the tested fungicides degenerate according to pseudo-first-order kinetics. Based on the findings, we concluded that photocatalytic degradation of pesticides in soils are faster than photolysis.

Moringa oleifera is rich in bioactive compounds such as beta-carotene, which have high nutritional values and antimicrobial applications. Several studies have confirmed that bioactive-compound-based herbal medicines extracted from the leaves, seeds, fruits and shoots of M. oleifera are vital to cure many diseases and infections, and for the healing of wounds. The β-carotene is a naturally occurring bioactive compound encoded by zeta-carotene desaturase (ZDS) and phytoene synthase (PSY) genes. In the current study, computational analyses were performed to identify and characterize ZDS and PSY genes retrieved from Arabidopsis thaliana (as reference) and these were compared with the corresponding genes in M. oleifera, Brassica napus, Brassica rapa, Brassica oleracea and Bixa orellana. The BLAST results revealed that all the plant species considered in this study encode β-carotene genes with 80–100% similarity. The Pfam analysis on β-carotene genes of all the investigated plants confirmed that they belong to the same protein family and domain. Similarly, phylogenetic analysis revealed that β-carotene genes of M. oleifera belong to the same ancestral class. Using the ZDS and PSY genes of Arabidopsis thaliana as a reference, we conducted qRT-PCR analysis on RNA extracted from the leaves of M. oleifera, Brassica napus, Brassica rapa and Bixa orellana. It was noted that the most significant gene expression occurred in the leaves of the studied medicinal plants. We concluded that not only are the leaves of M. oleifera an effective source of bioactive compounds including beta carotene, but also the leaves of Brassica napus, Brassica rapa and Bixa orellana can be employed as antibiotics and antioxidants against bacterial or microbial infections.

Sr _1-x Gd _x TiO _3 (0.00 ≤ x ≤ 0.11) ceramics by the addition of Gd ^3+ on A-sites, were processed and fabricated through the conventional sintering method and optimised the sintering temperature at 1390 °C–1470 °C for 2 h. The experimentation shows that all ceramics are possessed by cubic structure, in which the increment of Gd ^3+ content, in terms of x, decreases the lattice parameters of the ceramics, as well as affects the grain size. Comparing the results to pure SrTiO _3 (STO) compounds, the addition of Gd ^3+ lowers the mass loss, increased the conductivity as well as permittivity by decreasing the dielectric losses at lower frequencies. The x = 0.03 and 0.01 evidenced the maximum Seeback Coefficient, ∼281 μ V K ^−1 at ∼370 K confirming the higher carrier concentration. Also, the magnetic properties as a function of Gd ^3+ ions doped with STO showed gradual improvement, showing maximum saturation with the maximum concentration of x.

Porous carbons are highly attractive and demanding materials which could be prepared using biomass waste; thus, they are promising for enhanced electrochemical capacitive performance in capacitors and cycling efficiency in Li-ion batteries. Herein, biomass (rice husk)-derived activated carbon was synthesized via a facile chemical route and used as anode materials for Li-ion batteries. Various characterization techniques were used to study the structural and morphological properties of the prepared activated carbon. The prepared activated carbon possessed a carbon structure with a certain degree of amorphousness. The morphology of the activated carbon was of spherical shape with a particle size of ~40–90 nm. Raman studies revealed the characteristic peaks of carbon present in the prepared activated carbon. The electrochemical studies evaluated for the fabricated coin cell with the activated carbon anode showed that the cell delivered a discharge capacity of ~321 mAhg−1 at a current density of 100 mAg−1 for the first cycle, and maintained a capacity of ~253 mAhg−1 for 400 cycles. The capacity retention was found to be higher (~81%) with 92.3% coulombic efficiency even after 400 cycles, which showed excellent cyclic reversibility and stability compared to commercial activated carbon. These results allow the waste biomass-derived anode to overcome the problem of cyclic stability and capacity performance. This study provides an insight for the fabrication of anodes from the rice husk which can be redirected into creating valuable renewable energy storage devices in the future, and the product could be a socially and ethically acceptable product.

The doping of magnesium on lithium aluminium borate phosphor is reported in this study. A solid-state sintering technique was employed as the borate samples were synthesized. This report focuses on the structural, optical, thermoluminescence, and kinetic analyses of the main glow peak. The structural properties of lithium aluminium borates improved due to the magnesium dopants used. Differences in the crystallite size and particle size were 38.85–67.35 nm and 50–60 nm, respectively, and these results were obtained from the analyzed X-ray diffractogram and scanning electron spectroscopy. The energy band gaps obtained from the direct transition of borate phosphor materials were within the range of 3.00–4.40 eV, and the doped samples gave a higher energy band gap. A decrease in the TGA (%) exhibited a weight loss or water loss for the undoped, 0.1% Mg, and 0.3% Mg-doped lithium aluminium borate materials. The glow curve measured at a heat rate of 1 °C·s−1 after irradiation to 50 Gy revealed four peaks related to the magnesium doped lithium aluminium borate. The main glow peak was observed at 86 °C. Activation energy was extracted from the main glow peak by using kinetic analysis which involves the initial rise, deconvolution, and variable heating rate approach, and it was approximately 0.67 ± 0.03 eV. A shift in the main glow peak curve from 86 to 110 °C was recognized for the magnesium-doped lithium aluminium borate when it was irradiated from 1 to 300 Gy.

In this paper, the sol-gel technique has been employed to prepare the pure and TM (Mn, Cr) doped BiFeO3 nanoparticles. The synthesized nanoparticles were characterized using X-ray diffraction, UV-vis spectroscopy, photoluminescence, and dielectric measurements. Crystal structural analysis infers that pure and TM-doped BiFeO3 nanoparticles displayed a rhombohedral distorted perovskite structure with R3c space group, along with a minor phase of Bi2Fe4O9. Lattice parameters have been found to decrease with TM doping. The particle size, measured with the help of the XRD spectra, was found to decrease from 54.4 nm to 38.7 nm with TM doping. The bandgap, determined using the UV-vis spectra, was observed to be 1.92, 1.66, and 1.54 eV for undoped, 5% Mn, and 5% Cr-doped BiFeO3 nanoparticles, respectively. The dielectric constant shows a normal dispersion behavior at room temperature and its value increases with TM doping. The ac conductivity also increases with TM doping in BiFeO3 nanoparticles.

In this work, the chemical bath deposition (CBD) technique was utilized in the synthesis of transition metals/GO nanocomposites (Co3O4/MnO2/NiO/GO) for applications in supercapacitor electrodes. The nanocomposites after characterization showed that the electrically conductive nature and wide surface area of graphene oxide (GO) accounted for its incorporation into the nanocomposites. The synergy between the nanocomposites accounts for their improved performance and stable phase. The XRD results revealed cubic, orthorhombic, cubic, and mixed phases for the Co3O4/GO (CG), MnO2/GO (MG), NiO/GO (NG), and Co3O4/MnO2/NiO/GO (CMNG), respectively; their morphologies showed platelet nanoparticles with few agglomerates, with an average particle size of 69 ± 12 nm, 37 ± 09 nm, 58 ± 36 nm, and 36 ± 08 nm, respectively. For the produced materials, electrochemical results revealed maximum specific capacitance values of 2482 F/g from cyclic voltammograms and 1280.48 F/g from the galvanometric test. The results showed that the composites outperform single transition metal oxide (TMO) electrodes, with graphene oxide boosting the electrode performance.

Herein, we present an electrocatalyst constructed by zinc oxide hexagonal prisms/phosphorus-doped carbon nitride wrinkles (ZnO HPs/P-CN) prepared via a facile sonochemical method towards the detection of nitrofurantoin (NF). The ZnO HPs/P-CN-sensing platform showed amplified response and low-peak potential compared with other electrodes. The exceptional electrochemical performance could be credited to ideal architecture, rapid electron/charge transfer, good conductivity, and abundant active sites in the ZnO HPs/P-CN composite. Resulting from these merits, the ZnO HPs/P-CN-modified electrode delivered rapid response (2 s), a low detection limit (2 nM), good linear range (0.01–111 µM), high sensitivity (4.62 µA µM−1 cm2), better selectivity, decent stability (±97.6%), and reproducibility towards electrochemical detection of NF. We further demonstrated the feasibility of the proposed ZnO HPs/P-CN sensor for detecting NF in samples of water and human urine. All the above features make our proposed ZnO HPs/P-CN sensor a most promising probe for detecting NF in natural samples.

In this paper, the photocatalytic effect of zirconia/laser-induced graphene on the degradation of methylene blue was comprehensively studied. The average particle size measured by HRTEM is 6 nm for both ZrO2 and ZrO2/G10 samples, which explains the high-quality TEM imaging of isolated squared sections of cubic particles. The weight percentages of Zr, O, and C elements using EDX were 72.16, 18.56, and 9.28, respectively. These results confirm the formation of binary composites. Moreover, Raman scattering exhibited that the spectrum of pure ZrO2 was difficult to be detected due to the high luminescence. However, ZrO2 vibration modes were detected for ZrO2-graphene nanocomposites at 1012, 615, 246, and 150 cm−1. A shift of the D- and G-bands of graphene were observed, where D-peak and G-peak were observed at 1370 and 1575 cm−1 for ZrO2/5G and, 1361 and 1565 cm−1 for ZrO2/10G, respectively. The shift is ascribed to the incorporation of graphene into the surface of the oxide material. Compared to ZrO2, the newly fabricated ZrO2-graphene nanocomposites have the advantage of increased photocatalytic effects. An adsorbent concentration of 5 and 10 mg·L−1 at room temperature over 240 min was observed to be suitable experimental conditions. The kinetic results indicate that the practical results obtained are well expressed by the first-order kinetic model at different concentrations. In addition, the results showed that the addition of graphene led to a significant degradation process increase. The results also showed the significant effect of the investigated ZrO2-graphene nanocomposites on the decomposition of methylene blue cation. The decomposition of cationic pollutants showed a synergistic effect of the ZrO2-graphene nanocomposites on wastewater treatment.

Water pollution and deficient energy are the main challenges for the scientific society across the world. In this trend, new approaches include designing zinc oxide nanohybrids to be very active in sunlight. In this line, organic and magnetic species intercalate among the nanolayers of Al/Zn to build inorganic-magnetic-organic nanohybrid structures. A series of nanolayered and nanohybrid structures have been prepared through intercalating very fine particles of cobalt iron oxide nanocomposites and long chains of organic fatty acids such as n-capric acid and stearic acid inside the nanolayered structures of Al/Zn. By thermal treatment, zinc oxide nanohybrids have been prepared and used for purifying water from colored pollutants using solar energy. The optical measurements have shown that the nanohybrid structure of zinc oxide leads to a clear reduction of band gap energy from 3.30 eV to 2.60 eV to be effective in sunlight. In this line, a complete removal of the colored pollutants (naphthol green B) was achieved after ten minutes in the presence of zinc oxide nanohybrid and sunlight. Finally, this new approach for designing photoactive nanohybrids leads to positive results for facing the energy- and water-related problems through using renewable and non-polluting energy for purifying water.

Energy and water related problems have attracted strong attention from scientists across the world because of deficient energy and water pollution. Following this line, new strategy depended on preparing nanolayers of Al/Zn and magnetic nanoparticles of cobalt iron oxides nanocomposite in addition to long chains of hydrocarbons of stearic acid to be used as roofs, fillers and pillars; respectively, to design optical-active nanohybrids in sunlight for removing the colored pollutants from water in few minutes. By using long chains of hydrocarbons of stearic acid, X-ray diffraction (XRD) results and TEM images showed expansion of the interlayered spacing from 0.76 nm to 2.02 nm and insertion of magnetic nanoparticles among the nanolayers of Al/Zn. The optical properties and activities showed that the nanohybrid structure based on zinc oxide led to clear reduction of the band gap energy from 3.3 eV to 2.75 eV to be effective in sunlight. Photocatalytic degradation of the dye of acid green 1 confirmed the high activity of the prepared zinc oxide nanohybrids because of a complete removal of the dye after ten minutes in sunlight. Finally, this strategy was effective for producing photo-active nanohybrids for using renewable and non-polluting energy for purifying water.

Advanced photo-active materials have attracted attention for their potential uses in water purification. In this study, a novel and facile route was used for designing nanohybrids to be valuable sources for producing effective photocatalysts for purifying water from the colored pollutants. Host-guest interaction and intercalation reactions used long chains of hydrocarbons of n-capric acid and stearic acid to facilitate incorporation of fine particles of cobalt iron oxide nanocomposite with the internal surface of the nanolayers of Al/Zn for building nanohybrids. The thermal decomposition of the prepared nanohybrids led to formation of zinc oxide nanoparticles doped with multi-oxides of magnetic and non-magnetic dopants. These dopants created new optical centers causing a strong reduction in the band gap energy from 3.30 eV to 2.60 eV. This positive effect was confirmed by a complete removal of the dye of Naphthol green B from water after 15 min of light irradiation. Moreover, a kinetic study showed that the reaction rate of photocatalytic degradation of the pollutants was faster than that of the conventional photocatalysts. Finally, this route was effective for producing benign and fast solutions for purifying water in addition to environment-related problems.

Hydrothermally synthesized electrodes of Co3O4@MnO2@NiO/GO were produced for use in supercapacitors. Graphene oxide (GO) was incorporated into the nanocomposites used for electrode synthesis due to its great surface area and electrical conductivity. The synergistic alliance among these composites and GO enhances electrode performance, life span, and stability. The structural properties obtained from the X-ray diffraction (XRD) results suggest that nanocomposites are crystalline in nature. The synergistic alliance among these composites and GO enhances electrode performance, life span, and stability. Performance assessment of these electrodes indicates that their characteristic performance was enhanced by C2+ radiation, with the uttermost performance witnessed for electrodes radiated with 5.0 × 1015 ions/cm2.

Oxide perovskites doped with rare-earth have shown change in optoelectronic properties with high dielectric constants. Herein, the structural, electronic, and optical characteristics of BaTiO3 doped with ytterbium at the Ba and Ti sites were studied by employing the first-principles density functional calculations. The Tran-Blaha modified Becke-Johnson (TB-mBJ) potential and GGA + U approaches have been used for determining the optoelectronic properties. We probed the impact of the ytterbium incorporation at the Ti and Ba sites into BaTiO3 by tuning of the structural geometry and electronic structure behavior and dielectric constants. A detailed analysis, of structural properties, reveals that lattice parameters of ytterbium doping shift slightly regarding those of pristine BaTiO3. The BaO and TiO bond lengths were reduced due to the crystalline structure lattice distortion. The band structures demonstrate that ytterbium doping has induced various changes in the electronic nature of BaTiO3 by creating a magnetism. For both Ba and Ti sites, ytterbium doping has strongly increased the BaTiO3 dielectric constants.

We investigated the effects of applying an external electric field on the electronic properties of Stone-Wales (SW) defective carbon-boron-nitride nanotubes (CBN) using first principles calculations. The defective CBN nanotubes were modeled by introducing Stone–Wales defects in the boron-nitride segment (BN-SW), the carbon segment (C-SW), and the carbon-boron-nitride interface segment (CBN-SW). Initially, we studied the formation energies and the structural stability for all models. As a result of adding the SW defects, the calculated bandgap values of the C-SW and CBN-SW models showed significant changes compared to the pristine CBN nanotube. Meanwhile, the BN-SW model showed a slight bandgap change because of the strong covalent bonding between the boron and nitrogen atoms. Applying a transverse electric field induced a fast bandgap closing response in all models, indicating a rapid semiconductor-to-metal phase transition. The defective C-SW and CBN-SW models demonstrated unique bandgap closing patterns in response to applied transverse and longitudinal electric fields, while pristine and BN-SW models had similar bandgap responses.

In the current study, we report on the dielectric behavior of colossal-dielectric-constant Na1/2La1/2Cu3Ti4O12 (NLCTO) ceramics prepared by mechanochemical synthesis and spark plasma sintering (SPS) at 850 °C, 900 °C, and 925 °C for 10 min. X-ray powder diffraction analysis showed that all the ceramics have a cubic phase. Scanning electron microscope observations revealed an increase in the average grain size from 175 to 300 nm with an increase in the sintering temperature. SPS NLCTO ceramics showed a room-temperature colossal dielectric constant (>103) and a comparatively high dielectric loss (>0.1) over most of the studied frequency range (1 Hz–40 MHz). Two relaxation peaks were observed in the spectra of the electrical modulus and attributed to the response of grain and grain boundary. According to the Nyquist plots of complex impedance, the SPS NLCTO ceramics have semiconductor grains surrounded by electrically resistive grain boundaries. The colossal dielectric constant of SPS NLCTO ceramics was attributed to the internal barrier layer capacitance (IBLC) effect. The high dielectric loss is thought to be due to the low resistivity of the grain boundary of SPS NLCTO.

Doping processes for optical materials are one of the driving forces for developing efficient and clean technologies for decontamination of aquatic effluents through lowering their band gap energy to become effective in sunlight. The current study has used a non-conventional technique for doping zinc oxide by multi metals, non-metals and organic dyes through a one-step process. In this trend, Zn-Al nanolayered structures have been used as hosts for building host–guest interactions. Organic dyes that have inorganic species of iron, nitrogen and sulfur have been used as guests in the intercalation reactions of Zn-Al layered double hydroxides. By intercalating green dyes, organic–inorganic nanohybrids were formed as nanolayered structures with expanding interlayered spacing to 2.1 nm. By changing the concentration of green dyes and thermal treatment, series of nanofibers and nanoplates of zinc oxides were formed and doped by aluminum, iron and sulfur in addition to colored species. The optical properties of the multi-doped zinc oxide indicated that it became suitable for solar applications because its band gap energy decreased from 3.30 eV to 2.80 eV. The experimental and kinetic results of the multi-doped zinc oxide concluded that the colored pollutants were effectively removed during 50 min of sunlight irradiation.

In this work, we report a new approach for detecting SARS-CoV-2 RBD protein (RBD) using the surface-enhanced Raman spectroscopy (SERS) technique. The optical enhancement was obtained thanks to the preparation of nanostructured Ag/Au substrates. Fabricated Au/Ag nanostructures were used in the SERS experiment for RBD protein detection. SERS substrates show higher capabilities and sensitivity to detect RBD protein in a short time (3 s) and with very low power. We were able to push the detection limit of proteins to a single protein detection level of 1 pM. The latter is equivalent to 1 fM as a detection limit of viruses. Additionally, we have shown that the SERS technique was useful to figure out the presence of RBD protein on antibody functionalized substrates. In this case, the SERS detection was based on protein-antibody recognition, which led to shifts in the Raman peaks and allowed signal discrimination between RBD and other targets such as Bovine serum albumin (BSA) protein. A perfect agreement between a 3D simulated model based on finite element method and experiment was reported confirming the SERS frequency shift potential for trace proteins detection. Our results could open the way to develop a new prototype based on SERS sensitivity and selectivity for rapid detection at a very low concentration of virus and even at a single protein level.

In the present work we have studied the transport and dielectric behavior of BaTi0.7Zr0.3O3 (BTZ30) relaxor ferroelectrics prepared by spark plasma sintering. Nanocrystalline powder of BTZ30 was obtained by solid state reaction followed by mechanical milling. Fine and coarse-grained ceramics of BTZ30 were prepared by spark plasma sintering at 1100 and 1400 °C, respectively. The obtained materials were characterized by X-ray diffraction and scanning electron microscopy. The grain size of the BTZ30 ceramics increased from 200 nm to 3–5 μm as the sintering temperature was increased from 1100 °C to 1400 °C. The electrical and dielectric properties of BTZ30 ceramics were studied by impedance spectroscopy over −150 to +200 °C temperature range. The dielectric constant exhibits very large values >105 for the spark plasma sintered ceramics associated with very high dielectric loss and electrical conductivity. The insulating nature of the BTZ30 ceramics could be retained by re-oxidation of the samples. The dielectric data of the annealed have been analyzed by the modified Curie-Weiss law and the relaxation process in the materials was fitted by Vogel-Fulcher model. Keywords: Barium titanate zirconate, Relaxor ferroelectrics, Spark plasma sintering, Dielectric properties

In this study, high specific surface areas (SSAs) of anatase titanium dioxide (TiO2) quantum dots (QDs) were successfully synthesized through a novel one-step microwave–hydrothermal method in rapid synthesis time (20 min) without further heat treatment. XRD analysis and HR-TEM images showed that the as-prepared TiO2 QDs of approximately 2 nm size have high crystallinity with anatase phase. Optical properties showed that the energy band gap (Eg) of as-prepared TiO2 QDs was 3.60 eV, which is higher than the standard TiO2 band gap, which might be due to the quantum size effect. Raman studies showed shifting and broadening of the peaks of TiO2 QDs due to the reduction of the crystallite size. The obtained Brunauer–Emmett–Teller specific surface area (381 m2 g−1) of TiO2 QDs is greater than the surface area (181 m2 g−1) of commercial TiO2 nanoparticles. The photocatalytic activities of TiO2 QDs were conducted by the inactivation of Escherichia coli under ultraviolet light irradiation and compared with commercially available anatase TiO2 nanoparticles. The photocatalytic inactivation ability of E. coli was estimated to be 91% at 60 µg ml−1 for TiO2 QDs, which is superior to the commercial TiO2 nanoparticles. Hence, the present study provides new insight into the rapid synthesis of TiO2 QDs without any annealing treatment to increase the absorbance of ultraviolet light for superior photocatalytic inactivation ability of E. coli.

The present study aims to enhance the optical properties of barium titanate through narrowing its band gap energy to be effective for photocatalytic reactions in sunlight and be useful for solar cells. This target was achieved through growth of the hollandite phase instead of the perovskite phase inside the barium titanate crystals. By using solvent thermal reactions and thermal treatment at different temperatures (250 °C, 600 °C, and 900 °C), the hollandite phase of barium titanate was successfully obtained and confirmed through X-ray diffraction (XRD), Raman spectra and scanning electron microscopy techniques. XRD patterns showed a clear hollandite phase of barium titanium oxides for the sample calcined at 900 °C (BT1-900); however, the samples at 600 °C showed the presence of mixed phases. The mean crystallite size of the BT1-900 sample was found to be 38 nm. Morphological images revealed that the hollandite phase of barium titanate consisted of a mixed morphology of spheres and sheet-like features. The optical properties of barium titanate showed that its absorption edge shifted to the visible region and indicated band gap energy tuning ranging from 1.75 eV to 2.3 eV. Photocatalytic studies showed the complete and fast decolorization and mineralization of green pollutants (naphthol green B; NGB) in the prepared barium titanate with hollandite phase after illumination in sunlight for ten minutes. Finally, it can be concluded that the low band gap energy of barium titanate having the hollandite phase introduces beneficial structures for optical applications in sunlight.

The high risk of morbidity and mortality associated with SARS-CoV-2 has accelerated the development of many potential vaccines. However, these vaccines are designed against SARS-CoV-2 isolated in Wuhan, China, and thereby may not be effective against other SARS-CoV-2 variants such as the United Kingdom variant (VUI-202012/01). The UK SARS-CoV-2 variant possesses D614G mutation in the Spike protein, which impart it a high rate of infection. Therefore, newer strategies are warranted to design novel vaccines and drug candidates specifically designed against the mutated forms of SARS-CoV-2. One such strategy is to target ACE2 (angiotensin-converting enzyme2)–Spike protein RBD (receptor binding domain) interaction. Here, we generated a homology model of Spike protein RBD of SARS-CoV-2 UK strain and screened a marine seaweed database employing different computational approaches. On the basis of high-throughput virtual screening, standard precision, and extra precision molecular docking, we identified BE011 (Dieckol) as the most potent compounds against RBD. However, Dieckol did not display drug-like properties, and thus different derivatives of it were generated in silico and evaluated for binding potential and drug-like properties. One Dieckol derivative (DK07) displayed good binding affinity for RBD along with acceptable physicochemical, pharmacokinetic, drug-likeness, and ADMET properties. Analysis of the RBD–DK07 interaction suggested the formation of hydrogen bonds, electrostatic interactions, and hydrophobic interactions with key residues mediating the ACE2–RBD interaction. Molecular dynamics simulation confirmed the stability of the RBD–DK07 complex. Free energy calculations suggested the primary role of electrostatic and Van der Waals’ interaction in stabilizing the RBD–DK07 complex. Thus, DK07 may be developed as a potential inhibitor of the RBD–ACE2 interaction. However, these results warrant further validation by in vitro and in vivo studies.

La2/3Cu3Ti4O12 (LCTO) powder has been synthesized by the mechanochemical milling technique. The pelletized powder was conventionally sintered for 10 h at a temperature range of 975–1025 °C, which is a lower temperature process compared to the standard solid-state reaction. X-ray diffraction analysis revealed a cubic phase for the current LCTO ceramics. The grain size of the sintered ceramics was found to increase from 1.5 ± 0.5 to 2.3 ± 0.5 μm with an increase in sintering temperature from 975 to 1025 °C. The impedance results show that the grain conductivity is more than three orders of magnitude larger than the grain boundary conductivity for LCTO ceramics. All the samples showed a giant dielectric constant (1.7 × 103–3.4 × 103) and dielectric loss (0.09–0.17) at 300 K and 10 kHz. The giant dielectric constant of the current samples was attributed to the effect of internal barrier layer capacitances due to their electrically inhomogeneous structure.

In the present work, we studied the effects of substitutional Sm3+ ions on the ionic conduction properties of Li5+2xLa3Nb2−xSmxO12 (LLN-Sm) ceramics with x = 0.0—0.6. The investigated final ceramics, prepared by solid state reaction, were sintered at 1000 °C for 12 h. XRD investigations showed the formation of the cubic garnet phase for all of the studied samples. The ionic conductivity was found to increase with Sm3+ content, with the highest value of 7.04 × 10−5 S/cm for the Li5+2xLa3Nb2−xSmxO12 sample compared to 7.49 × 10−6 S/cm for the pure LLN sample, both at RT. Lithium ion mobilities of LLN-Sm garnets at different temperatures were estimated. Considerable enhancement of mobility, the main factor leading to ionic conductivity improvement, was obtained for samples with Sm3+ substitutions. Relaxation processes were studied by the electric modulus, and the corresponding activation energy was found to be very similar to the ionic conduction process.

The presence of heavy metals in increased concentrations in the environment has become a global environmental concern. This rapid increase in heavy metals in the environment is attributed to enhanced industrial and mining activities. Metal ions possess a lengthy half-life and property to bioaccumulate, are non-biodegradable and, thus, are a threat to the human health. A number of conventional spectroscopic and chromatographic techniques are being used for the detection of heavy metals, but these suffer from various limitations. Nano-based sensors have emerged as potential candidates for the sensitive and selective detection of heavy metals. Thus, the present study was focused on the synthesis of selenium nanoparticles (SeNPs) by using selenite-reducing bacteria in the development of a heavy metal toxicity biosensor. During the biosynthesis of selenium nanoparticles, supernatants of the overnight-grown culture were treated with Na2SeO32− and incubated for 24 h at 37 °C. The as-synthesized nanoparticles were characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) and transmission electron microscopy (TEM) analyses. XRD and TEM results confirmed the formation of SeNPs in sizes ranging from 35 to 40 nm, with face-centered cubic (FCC) structures. The bioreduction process and validation of the formation of SeNPs was further confirmed by FTIR studies. The reduction in the biosynthesis of SeNPs using bacterial metabolite due to heavy metal cytotoxicity was analyzed by the colorimetric bioassay (SE Assay). The inhibition of selenite reduction and loss of red color in the presence of heavy metals may serve as a biosensor for heavy metal toxicity analysis. Thus, this biosensor development is aimed at improving the sensitivity and specificity of analytic detection.

Vertical Agx/TiO2 nanorods were successfully grown by a simple oxidation method of a Ti-Ag coating. The samples were grown in the phase of ceramic-like materials, which can be reusable for many cycles for photocatalysis applications. These ceramic-like Agx/TiO2 nanostructures were prepared by the spin-coating of silver nitrate onto Ti sheets. The presence of silver on the surface of the Ti sheet during the oxidation process helped in the growth of one-dimensional nanostructures. The physical properties of the fabricated ceramic-like nanostructures were studied by varying the concentration of silver on the Ti-sheet before the oxidation. One-dimensional nanostructures with an average size varying within the range of 200–500 nm were grown. The presence of silver made the nanostructure vertically directed. The nanorods were dense at the low and medium concentrations of 5, 10, and 20 mM of silver in contrary to high silver concentrations, where the nanorods were very sparse at 40 mM. Structural analysis showed the anatase and rutile structure of pure TiO2 with distinguishing diffraction lines A(101) and R(110); however, Agx/TiO2 showed a dominant orientation of A(101), confirming the 1D growth. Raman spectra confirmed the presence of TiO2 via the observation of its corresponding phonon modes. The photocatalysis properties of the fabricated ceramic-like nanostructures were performed on methylene blue (MB) as a known target dye. The low- and medium-silver-concentration samples showed a high photocatalytic activity compared to the pure and high-silver-concentration samples.

Development of electrochemical supercapacitor electrode is the best way to improve the performance and conductivity of the alone materials and support energy storage devices. In this work, cyanate anions have used as building blocks to build series of nanolayered materials based on Ti/Ni layered double hydroxides (LDHs). The structural and morphological characteristics of the prepared Ti/Ni LDHs were examined using different techniques. The electrochemical supercapacitive behavior of the prepared LDHs was observed in the three-assembly electrochemical cell. These results showed that the optimized ratio of the nickel and titanium plays an important role to enhance the electrochemical performance of the LDHs. The optimized Ti/Ni LDHs, which has the highest content of titanium, showed the highest specific capacitance (675 F/g) value. In this trend, this LDH also retain a high percentage of the cyclic retention after long cyclic charging-discharging process. The enhanced performance could be due to the double layer structure, enough interplanar distance between the layer, and large number of exposed active site within the double layer structure of the LDHs. Finally, although there are no reports for the electrochemical supercapacitive performance of Ti/Ni LDHs in the literature, it is interesting to produce a new candidate for energy storage applications.

Development of optical materials has attracted strong attention from scientists across the world to obtain low band gap energy and become active in field of solar energy. This challenge, which cannot be accomplished by the usual techniques, has overcome through the current study using non-conventional techniques. This study has used explosive reactions to convert non-optical alumina to series of new optical nanocomposites with very low band gap energy for the first time. In this trend, alumina nanoparticles were prepared and modified by explosive reactions using ammonium nitrate as a solid fuel. By using methanol or ethanol as a source of carbon species, three nanocomposites were produced indicating a gradual reduction of the band gap energy of alumina from 4.34 eV to 1.60 eV. These nanocomposites were obtained by modifying alumina via two different carbon species; core-shell structure and carbon nanotubes. This modification led to sharp reduction for the band gap energy to become very sensitive in sunlight. Therefore, these nanocomposites caused fast decolorization and mineralization of green dyes after illuminating in sunlight for ten minutes. Finally, it can be concluded that reduction of the band gap energy introduces new optical materials for developing optical nano-devices and solar cells.

Nanocomposite films grown by incorporating varying concentrations of Yttrium, a d-block rare-earth ion, into the binary chalcogenide Arsenic selenide host matrix is here presented. Films were grown via the wet-chemical electro-deposition technique and characterized for structural, optical, surface morphology, and photoluminescence (PL) properties. The X-ray Diffraction (XRD) result of the host matrix (pristine film) showed films of monoclinic structure with an average grain size of 36.2 nm. The composite films, on the other hand, had both cubic YAs and tetragonal YSe structures with average size within 36.5–46.8 nm. The fairly homogeneous nano-sized films are shown by the Scanning Electron Microscopy (SEM) micrographs while the two phases of the composite films present in the XRD patterns were confirmed by the Raman shifts due to the cleavage of the As-Se host matrix and formation of new structural units. The refractive index peaked at 2.63 within 350–600 nm. The bandgap energy lies in the range of 3.84–3.95 eV with a slight decrease with increasing Y addition; while the PL spectra depict emission bands across the Vis-NIR spectral regions. Theoretically, the density functional theory (DFT) simulations provided insight into the changes induced in the structure, bonding, and electronic properties. Besides reducing the bandgap of the As2Se3, the yttrium addition has induced a lone pair p-states of Se contributing nearby to Fermi energy level. The optical constants, and structural and electronic features of the films obtained present suitable features of film for IR applications as well as in optoelectronics.

Na _1/2 Y _1/2 Cu _3 Ti _4 O _12 (NYCTO) ceramics with giant dielectric constant ( ε ′) were synthesized by simple reactive sintering. NYCTO nanopowder was first synthesized using high energy ball-mill. Then the pelletized powder was sintered in air at temperatures in the range 975 °C to 1050 °C for 10–20 h. The obtained ceramics showed pure CaCu _3 Ti _4 O _12 (CCTO)-like cubic phase as revealed by x-ray diffraction measurements. Field effect-SEM observations showed that the grain size increases from 2 μ m to 5 μ m with increasing sintering temperature. NYCTO samples sintered at temperatures higher than 975 °C showed giant dielectric constant (10 ^3 –10 ^4 ) over most of the frequency range. The minimum dielectric loss (tan δ ) of ∼0.055 at 300 K has been approved for the ceramic sample sintered at 1050 °C. Impedance and modulus spectra of the current samples showed two relaxations related to semiconductor (grain) and high resistance (grain-boundaries) elements. The activation energy for conduction located in the range 0.1–0.5 eV highlighted the role of single ionized oxygen vacancies in the dielectric properties of the investigated NYCTO ceramics.

The plate-like structure is the most familiar morphology for conventional layered double hydroxides (LDHs) in case their structures consist of divalent and trivalent cations in their layers. In this study, nanofibers and nanoneedles of Co−Si LDHs were prepared for the first time. By the inclusion of zirconium inside the nanolayers of LDH structures, their plates were formed and transformed to nanofibers. These nanofibers were modified by the insertion of titanium to build again plate-like morphology for the LDH structure. This morphology controlling was studied and explained by a dual anions intercalation process. The optical properties of Co−Si LDHs indicated that the incorporation of zirconium within their nanolayers decreased the band gap energy from 4.4 eV to 2.9 eV. Following the same behavior, the insertion of titanium besides zirconium within the nanolayers of Co−Si LDHs caused a further reduction in the band gap energy, which became 2.85 eV. Although there is no data for the optical properties of Co−Si LDHs in the literature, it is interesting to observe the low band gap energy for Co−Si LDHs to become more suitable for optical applications. These results concluded that the reduction of the band gap energy and the formation of nanofibers introduce new optical materials for developing and designing optical nanodevices.

In this work, a simple and cost-effective electrochemical anodization technique was adopted to rapidly grow TiO2 nanotube arrays on a Ti current collector and to utilize the synthesized materials as potential electrodes for supercapacitors. To accelerate the growth of the TiO2 nanotube arrays, lactic acid was used as an electrolyte additive. The as-prepared TiO2 nanotube arrays with a high aspect ratio were strongly adhered to the Ti substrate. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results confirmed that the TiO2 nanotube arrays were crystallized in the anatase phase. TEM images confirmed the nanotublar-like morphology of the TiO2 nanotubes, which had a tube length and a diameter of ~16 and ~80 nm, respectively. The electrochemical performance of the TiO2 nanotube array electrodes was evaluated using the cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge (GCD) measurements. Excellent electrochemical response was observed for the electrodes based on the TiO2 nanotube arrays, as the cells delivered a high specific capacitance of 5.12 mF/cm2 at a scan rate of 100 mV/s and a current density of 100 µA/cm2. The initial capacity was maintained for more than 250 cycles. Further, a remarkable rate capability response was observed, as the cell retained 88% of the initial areal capacitance when the scan rate was increased from 10 to 500 mV/s. The results suggest the suitability of TiO2 nanotube arrays as electrode materials for commercial supercapacitor applications.