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Highlights The advantages of biomass materials for electromagnetic interference (EMI) shielding are analyzed, the mechanism of EMI shielding is summarized, and the factors affecting EMI shielding are analyzed systematically. Various biomass materials (wood, bamboo, lignin, cellulose) were modified to obtain unique structures and improve EMI shielding performance. The problems encountered in the application of biomass materials for EMI shielding are summarized, and the potential development and application in the future are prospected.

Highlights The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment.

Abstract As key developmental regulators, HOX cluster genes have varied and context-specific roles in normal and malignant hematopoiesis. A complex interaction of transcription factors, epigenetic regulators, long non-coding RNAs and chromatin structural changes orchestrate HOX expression in leukemia cells. In this review we summarize molecular mechanisms underlying HOX regulation in clinical subsets of AML, with a focus on NPM1 mutated (NPM1mut) AML comprising a third of all AML patients. While the leukemia initiating function of the NPM1 mutation is clearly dependent on HOX activity, the favorable treatment responses in these patients with upregulation of HOX cluster genes is a poorly understood paradoxical observation. Recent data confirm FOXM1 as a suppressor of HOX activity and a well-known binding partner of NPM suggesting that FOXM1 inactivation may mediate the effect of cytoplasmic NPM on HOX upregulation. Conversely the residual nuclear fraction of mutant NPM has also been recently shown to have chromatin modifying effects permissive to HOX expression. Recent identification of the menin-MLL interaction as a critical vulnerability of HOX-dependent AML has fueled the development of menin inhibitors that are clinically active in NPM1 and MLL rearranged AML despite inconsistent suppression of the HOX locus. Insights into context-specific regulation of HOX in AML may provide a solid foundation for targeting this common vulnerability across several major AML subtypes.

The double perovskites became appealing over time for solar cells and optoelectronic applications due to their extraordinary optical and transport properties. Here, we investigate the optical and thermoelectric behavior of a newly developed perovskite X2AgBiI6 (X = K, Rb, Cs) DPs. To ensure structural stability, the computed tolerance factor falls in the appropriate range. The formation energy has also been incorporated for thermodynamic stability. The reported band gaps (1.35, 1.30, 1.26) eV for (K, Rb, Cs) fall in the ideal range which is extremely important for solar cells. Moreover, the studied DPs demonstrate light absorption characteristics in the visible wavelength range. The transport properties discussion has been provided in terms of electrical and lattice conductivities, Seebeck coefficient, and figure (ZT) of merit analysis. With an excellent ZT at room temperature and a suitable band gap for visible absorption, the presented DPs are promising for thermoelectric generators and solar cell applications.

Abstract Background A holding chamber (HC) was created to work with a vibrating mesh nebulizer (VMN) to boost the total inhalable dose for patients. In addition to the optional supply of supplemental oxygen, it facilitates intermittent and continuous nebulization. Our goal was to see how well a VMN coupled to a HC with a mouthpiece or valved facemask performed at varied oxygen flows starting at 0–6 L/min. In this study, we used a breathing simulator to simulate adults' spontaneous breathing patterns with a tidal volume of 500 mL and a 1:1 inhalation–exhalation ratio. For the combination of nebulizer and HC adapter with a valved facemask or mouthpiece, five determinations were made. Salbutamol was recovered and evaluated using high-performance liquid chromatography from the inhalation filter connected to the breathing simulator, the nebulizer reservoir chamber, and the HC. Results The amount of salbutamol in the nebulizer reservoir chamber and within the HC did not differ significantly when using a mouthpiece or a valved facemask. However, the supplied dose to the inhalation filter was increased until oxygen flow reached 2 and 3 L/min using the mouthpiece and valved facemask as interfaces, respectively. The supplied salbutamol was much higher at this flow than at the other oxygen flows. This was followed by a progressive reduction in the supplied salbutamol until the lowest given dose was reached at 6 L/min oxygen flow, p

The control of spin degree of freedom in electronics open new horizons to manipulate, transfer, and storage data at fasters speed. For this the structural, electronic, and magnetic characteristics of BaCr2X4 (X = S, Se, Te) spinels are addressed comprehensively. The more energy release in ferromagnetic states than antiferromagnetic states, and formation energy verified thermal stability in FM states. The Curie temperature, and spin polarization density have been reported for room temperature ferromagnetism. The detail and nature of ferromagnetism have illustrated by band structures, density of states, hybridization, double exchange mechanism, crystal field energy, exchange energies and exchange constants. The transfer of magnetic moment from Cr sites to other nonmagnetic sites (Ba, X) ensures the ferromagnetism due to exchange of electrons instead of clustering. Moreover, thermoelectric characteristics are explored with spin (↑) and spin (↓) separately in terms of conductivities, Seebeck coefficient, and power factor. Finally combined the spins to analyze the thermoelectric importance for real applications.

Nowadays double perovskites for renewable energy are emerging materials because of their interesting properties such as simple and stable crystal structure. In our study, we theoretically explored the optoelectronic along with mechanical and thermoelectric characteristics of X2InSbO6 (X = Sr, Ba) using density functional theory followed by Wein2k code. The thermodynamic and structural stabilities are determined based on the enthalpy of formation and tolerance factor. The ductile and brittle behavior has been checked by Passion and Pugh's ratios. The measured values of energy band gaps are 2.55 eV for Sr2InSbO6, and 1.75 eV for Ba2InSbO6. These compositions are potentially used in optoelectronic applications because their electronic characteristics are controllable. In the energy range 0–12 eV, the compositions under consideration exhibit a single-peaked response while the replacement of cation Sr with Ba caused a shift in optical structures towards lower energies. These compositions are also suitable for thermoelectric systems as they possess high values of the figure of merits at room temperature and the measured values are 0.77 for Sr2InSbO6 and 0.75 for Ba2InSbO6 are recorded.

Abstract This work reports the rational design of MnOx nanorods on 3D crushed reduced graphene oxide (MnOx/C-rGO) by chemical reduction of Ni-incorporated graphene oxide (GO) followed by chemical etching to remove Ni. The resulting MnOx/C-rGO composite synergistically integrates the electronic properties and geometry structure of MnOx and 3D C-rGO. As a result, MnOx/C-rGO shows a significantly higher specific capacitance (C sp) of 863 F g−1 than MnOx/2D graphene sheets (MnOx/S-rGO) (373 F g−1) and MnOx (200 F g−1) at a current density of 0.2 A g−1. Furthermore, when assembled into symmetric supercapacitors, the MnOx/C-rGO-based device delivers a higher C sp (288 F g−1) than MnOx/S-rGO-based device (75 F g−1) at a current density of 0.3 A g−1. The superior capacitive performance of the MnOx/C-rGO-based symmetric device is attributed to the enlarged accessible surface, reduced lamellar stacking of graphene, and improved ionic transport provided by the 3D architecture of MnOx/C-rGO. In addition, the MnOx/C-rGO-based device exhibits an energy density of 23 Wh kg−1 at a power density of 113 Wkg−1, and long-term cycling stability, demonstrating its promising potential for practical application. Graphical Abstract

The work reports a facile synthesis of high thermally stable nanocrystalline anatase TiO2 nanoparticles (NPs) doped with different atomic concentrations (0.5, 1.0, 3.0, and 6.0%) of Gd3+ and Nd3+ ions by a template-free and one-step solvothermal process, using titanium(IV) butoxide as a titanium precursor and dimethyl sulfoxide (DMSO) as a solvent. The structure and morphology of the Gd3+, Nd3+, and 0.5%Gd3+-0.5%Nd3+/doped TiO2 NPs have been characterized by using various analytical techniques. The Gd3+/ and Nd3+/TiO2 molar ratios were found to have a pronounced impact on the crystalline structure, size, and morphology of TiO2 NPs. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) studies revealed the proper substitution of Ti4+ by Gd3+ and Nd3+ ions in the TiO2 host lattice. The as-prepared Gdx/TiO2, Ndx/TiO2, and Gd1.0/Ndx/TiO2 bimetallic NPs, x = 0.5, 1.0, 3.0, and 6%, have been investigated as electrocatalysts for hydrogen evolution reaction (HER) in 1.0 M KOH solution using a variety of electrochemical techniques. At any doping percentage, the Gd1.0/Ndx/TiO2 bimetallic NPs showed higher HER catalytic performance than their corresponding counterparts, i.e., Gdx/TiO2 and Ndx/TiO2. Upon increasing the Nd content from 0.5 to 6.0%, the HER catalytic performance of the Gd1.0/Ndx/TiO2 bimetallic NPs was generally enhanced. Among the studied materials, the bimetallic Gd1.0/Nd6.0/TiO2 NPs emerged as the most promising catalyst with an onset potential of −22 mV vs. RHE, a Tafel slope of 109 mV dec−1, and an exchange current density of 0.72 mA cm−2. Such HER electrochemical kinetic parameters are close to those recorded by the commercial Pt/C (onset potential: −15 mV, Tafel slope: 106 mV dec−1, and exchange current density: 0.80 mA cm−2), and also comparable with those measured by the most active electrocatalysts reported in the literature. The synergistic interaction of Gd and Nd is thought to be the major cause of the bimetallic catalyst’s activity.

The double perovskites are promising for solar cells and other optoelectronic applications. In this article, the optoelectronic, transport characteristics of new double perovskites Ga2PdCl6, Ga2PdBr6, and Ga2PdI6 are addressed. The structural and thermodynamic stabilities have been addressed by tolerance factor, and positive frequency of phonon dispersion. The reported band gaps are 2.05 eV, 1.60 eV and 0.80 eV which increases their performance for solar cells. The Ga2PdBr6 is ideal for visible light solar cells with absorption band 400 nm–620 nm. The optical properties analyzed by dielectric constants, polarization, absorption of light, and optical losses. Thermoelectric characteristics has been explained by figure of merit (ZT) in terms of chemical potential, and kelvin temperature. The room temperature ZT (0.77, 0.76, 0.75) for Ga2PdX6 (X = Cl, Br, I) make them potential for thermoelectric applications.

The thrust to invent new materials and technology has been ever increasing due to technological challenges in progressive world. Among new materials, nanomaterials possess superior optical, electrical, magnetic, mechanical, and thermal properties, which have made them suitable for a multitude of applications. The present review paper deals with recent advances in properties of nanostructured glasses and composites in terms optical, electrical, mechanical and thermal properties. A brief discussion has been done on fabrication method of nanostructured glasses. The review of optical properties shows that nanostructured glasses show both direct and indirect band gap and this tuning of band gap depends on extent of nano structuring of samples. The electrical properties also show enhancement in electrical conductivity on nano-structuring of glasses compared to their bulk counterparts. The changes in mechanical and thermal properties of nanostructured glasses and composites are attributed to many microstructural features like grain size and shape, their distribution, pores and their distribution, other flaws/defects and their distribution, surface condition, impurity level, second phases/dopants, stress, duration of its application and temperature effect on the samples. Literature reports that nano structuring leads to enhanced phonon boundary scattering which reduces the thermal conductivity.

The structural alteration of carbon nitride (CN) for photocatalytic CO2 reduction is a promising research topic in the environmental and energy sectors. This work discusses the fabrication of photocatalyst through a heterojunction architecture obtained from the molecular engineering of electron-rich organic monomer 2,6-pyridinedicarboxylic acid (PDA) with CN precursor (CN/PDAx). The successful integration of PDA in the structure of CN served as a charge inducting entity to enhance charge separation and photocatalytic CO2 reduction under visible light (λ = 420 nm). The DFT results indicated that the upshift in the HOMO level of CN after integration of PDA in its framework was the most lawful for the charge separation and for obtaining a high reduction potential. As-synthesized photocatalysts were demonstrated for various integral analysises and after evaluating the process of photocatalytic CO2 reduction under visible light region (λ = 420 nm). The optimized sample CN/PDA10 has the most excellent photocatalytic activity producing 85.4 μmol/h of CO and 21.3 μmol/h of H2, achieving a 7.5-fold enhanced catalytic efficiency as compared to pure CN. We hope that this work will attract more attention to synthesizing efficient photocatalysts for energy production and environmental remediation.

Semiconductor-based photocatalytic technology is regarded as an efficient pathway for resolving the energy scarcity across the globe. In this regard, graphitic carbon nitride (g-C3N4)-based materials could be alternatively employed in photochemical applications such as photovoltaic energy generation via CO2 photoreduction and water splitting, along with natural resource purification via organic/inorganic pollutant degradation. Indeed, this kind of assertion has been made by considering the intrinsic physicochemical properties of g-C3N4 nanomaterials, owing to their increased surface area, quantum yield, surface charge isolation, distribution, and ease of modification through material configuration or incorporation of preferred interfacial capabilities. This review article has been designed to provide the most up-to-date information regarding the further assessment of the important advancements in fabrication along with photochemical applications of various g-C3N4 nanomaterials, while specifically focusing on the scientific reason behind its success in each assessment. The discovery of interventions to alleviate such restrictions and boost photocatalytic performance has gained substantial interest. Following photo-excitation fundamentals, this work explains two distinct photoexcitation mechanisms, the carrier and charge transfer techniques, wherein the significant exciting state impact of g-C3N4 has still not been widely focused on in past studies. In this regards, we cautiously introduce the updated advances and associated functions of the alteration techniques, including morphological features, elemental dopants, deficiency engineering, and heterojunction implemented in photocatalytic performance, which are equated from the carrier and charge transport perceptions. The future perspectives in designing and properly tuning the highly active hierarchical or copolymer g-C3N4 nanoparticles in a photocatalytic system, which may improve the renewable energy cultivation and reduction efficiency are critically deciphered in detail and outlined thoroughly.

Electrolytes are one of the most influential aspects determining the efficiency of electrochemical supercapacitors. Therefore, in this paper, we investigate the effect of introducing co-solvents of ester into ethylene carbonate (EC). The use of ester co-solvents in ethylene carbonate (EC) as an electrolyte for supercapacitors improves conductivity, electrochemical properties, and stability, allowing greater energy storage capacity and increased device durability. We synthesized extremely thin nanosheets of niobium silver sulfide using a hydrothermal process and mixed them with magnesium sulfate in different wt% ratios to produce Mg(NbAgS)x)(SO4)y. The synergistic effect of MgSO4 and NbS2 increased the storage capacity and energy density of the supercapattery. Multivalent ion storage in Mg(NbAgS)x(SO4)y enables the storage of a number of ions. The Mg(NbAgS)x)(SO4)y was directly deposited on a nickel foam substrate using a simple and innovative electrodeposition approach. The synthesized silver Mg(NbAgS)x)(SO4)y provided a maximum specific capacity of 2087 C/g at 2.0 A/g current density because of its substantial electrochemically active surface area and linked nanosheet channels which aid in ion transportation. The supercapattery was designed with Mg(NbAgS)x)(SO4)y and activated carbon (AC) achieved a high energy density of 79 Wh/kg in addition to its high power density of 420 W/kg. The supercapattery (Mg(NbAgS)x)(SO4)y//AC) was subjected to 15,000 consecutive cycles. The Coulombic efficiency of the device was 81% after 15,000 consecutive cycles while retaining a 78% capacity retention. This study reveals that the use of this novel electrode material (Mg(NbAgS)x(SO4)y) in ester-based electrolytes has great potential in supercapattery applications.

Despite the fast-developing momentum of perovskite solar cells (PSCs) toward flexible roll-to-roll solar energy harvesting panels, their long-term stability remains to be the challenging obstacle in terms of moisture, light sensitivity, and thermal stress. Compositional engineering including less usage of volatile methylammonium bromide (MABr) and incorporating more formamidinium iodide (FAI) promises more phase stability. In this work, an embedded carbon cloth in carbon paste is utilized as the back contact in PSCs (having optimized perovskite composition), resulting in a high power conversion efficiency (PCE) of 15.4%, and the as-fabricated devices retain 60% of the initial PCE after more than 180 h (at the experiment temperature of 85 °C and under 40% relative humidity). These results are from devices without any encapsulation or light soaking pre-treatments, whereas Au-based PSCs retain 45% of the initial PCE at the same conditions with rapid degradation. In addition, the long-term device stability results reveal that poly[bis(4–phenyl) (2,4,6–trimethylphenyl) amine] (PTAA) is a more stable polymeric hole-transport material (HTM) at the 85 °C thermal stress than the copper thiocyanate (CuSCN) inorganic HTM for carbon-based devices. These results pave the way toward modifying additive-free and polymeric HTM for scalable carbon-based PSCs.

The crystallinity properties of perovskite influence their optoelectrical performance in solar cell applications. We optimized the grain shape and crystallinity of perovskite film by annealing treatment from 130 to 170 °C under high humidity (relative humidity of 70%). We found that the grain size, grain interface, and grain morphology of the perovskite are optimized when the sample was annealed at 150 °C for 1 h in the air. At this condition, the perovskite film is composed of 250 nm crystalline shape grain and compact inter-grain structure with an invincible grain interface. Perovskite solar cells device analysis indicated that the device fabricated using the samples annealed at 150 °C produced the highest power conversion efficiency, namely 17.77%. The open circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) of the device are as high as 1.05 V, 22.27 mA/cm2, and 0.76, respectively. Optoelectrical dynamic analysis using transient photoluminescence and electrochemical impedance spectroscopies reveals that (i) carrier lifetime in the champion device can be up to 25 ns, which is almost double the carrier lifetime of the sample annealed at 130 °C. (ii) The interfacial charge transfer resistance is low in the champion device, i.e., ~20 Ω, which has a crystalline grain morphology, enabling active photocurrent extraction. Perovskite’s behavior under annealing treatment in high humidity conditions can be a guide for the industrialization of perovskite solar cells.

Layered double hydroxides (LDH) are regarded as attractive pseudocapacitive materials due to their impressive capacitive qualities that may be adjustable to their morphological features. However, the layered structure of LDH renders them susceptible to structural aggregation, which inhibits effective electrolyte transport and limits their practical applicability after limited exposure to active areas. Herein, we propose a simple template-free strategy to synthesize hierarchical hollow sphere NiMn-LDH material with high surface area and exposed active as anode material for supercapacitor application. The template-free approach enables the natural nucleation of Ni-Mn ions resulting in thin sheets that self-assemble into a hollow sphere, offering expended interlayer spaces and abundant redox-active active sites. The optimal NiMn-LDH-12 achieved a specific capacitance of 1010.4 F g−1 at a current density of 0.2 A g−1 with capacitance retention of 70% at 5 A g−1 after 5000 cycles with lower charge transfer impedance. When configured into an asymmetric supercapacitors (ASC) device as NiMn-LDH//AC, the material realized a specific capacitance of 192.4 F g−1 at a current density of 0.2 A g−1 with a good energy density of 47.9 Wh kg−1 and a power density of 196.8 W kg−1. The proposed morphological-tuning route is promising for designing template-free NiMn-LDHs spheres with practical pseudocapacitive characteristics.

In Figure 2a [...]

Prediction of new materials is crucial for the advancement of technology. Here, in this research work, the first-principle computation has been conducted utilizing the WIEN2K package to probe the structural, electronic, mechanical, and optical properties of barium-based chloroperovskites BaMCl3 (M = Ag, Cu) compounds. The optimized lattice constants are calculated for both compounds which are 9.90 Bohr for BaAgCl3 and 9.38 Bohr for BaCuCl3. To obtain better and more precise results for the electronic band’s structure, TDOS and PDOS (total and partial density of states), and the TB-mBJ potential approximation are employed. The indirect band gap (R–Γ) is found for both compounds having values of 1.173 eV and 2.30 eV for BaCuCl3 and BaAgCl3, respectively, which depicts its semiconducting nature. The calculation of elastic properties is conducted with IRelast code. The Cauchy pressure, Bulk modulus, Young’s modulus, Shear modulus, anisotropic ratio, Kleinman parameters, and Poisson’s ratio are calculated from the obtained elastic constants. The computation of elastic parameters indicates that the interested chloroperovskites are anisotropic, mechanically stable, hard to scratch, and ductile. From 0 eV to 40 eV incident photon energy ranges, the various optical parameter such as refractive index, absorption coefficient, dielectric function, reflectivity, extinction coefficient, and optical conductivity are analyzed. These compounds absorb maximum light within 5 to 25 eV incident photon energy. Hence, these materials are good light absorbers, therefore, they can be used in optoelectronic devices for high-frequency applications.

Air particulate matter with a diameter of 2.5 µm (PM2.5) were assembled for a whole year from the historical Jeddah district. Additional PM2.5 aerosols were collected during the autumn and winter seasons from another newly constructed district in Jeddah city (Alnaeem). The annual concentration of the total mass of the PM2.5 aerosols from the historical Jeddah site was found to be 43 ± 6 µg/m3. In addition, the average of the total mass concentration at the Alnaeem site was 61 ± 14 µg/m3. These values were greater than the annual mass concentration of the air quality standards of the European Commission (25 µg/m3) and the World Health Organization (10 µg/m3). The elemental analysis of the collected fine atmospheric aerosols was achieved by energy dispersive X-ray fluorescence (EDXRF) with three secondary targets (CaF2, Ge, and Mo). Quantitative elemental analyses of twenty-two (22) elements were achieved starting from the low atomic number element (Na) up to the high atomic number element (Pb). Although the historical Jeddah site is not well organized, the elemental concentrations and total mass concentrations were lower than those of the other site. The statistical analyses including enrichment factors, correlation analysis, and the principal component analysis revealed more information about the source identification of the PM2.5 aerosols collected from both locations. It was recognized that the elements Al, Si, K, Ca, Ti, Mn, Fe, Rb, and Sr originated from a natural source. On the other hand, the elements Ta, Br, Pb, Sc, Ni, Cu, Zn, and S originated from anthropogenic sources. Finally, the elements Na, Cl, and Br came mainly from the sea spray source.

Development of promising technologies to remove thallium as a highly poisonous contaminant is of great attention to guarantee the sustainable supplement of safe potable water and human well-being all around the world. Recently, adsorption has been introduced as a noteworthy technique to remove trace amount of thallium. In the past, the rate of thallium removal using the adsorption technique was relatively low due to the fact that this method was significantly influenced by the co-existing cations. To overcome this problem, more promising adsorbents such as nano-based materials have been developed. These adsorbents have shown great potential in the process of thallium removal due to their large surface area and superior selectivity. The main objective of this paper is to present a state-of-the-art review about the potential of nano-based form of disparate materials (i.e., titanium compounds, MnO2, ZnO, Al2O3 and multiwall carbon nanotubes) to separate thallium from water/waste water sources. Then, a systematic overview about acute/chronic toxicities of thallium for humans is aimed to be provided. Throughout the review, the authors aim to compare the negative and positive aspects of each treatment technique and offer promising technologies for thallium removal. At the end, an outlook on the recent advancements in the adsorption process of thallium using nanomaterials is provided.

Herein, we reported a unique photo device consisting of monolayer graphene and a few-layer rhenium diselenide (ReSe2) heterojunction. The prepared Gr/ReSe2-HS demonstrated an excellent mobility of 380 cm2/Vs, current on/off ratio ~ 104, photoresponsivity (R ~ 74 AW−1 @ 82 mW cm−2), detectivity (D* ~ 1.25 × 1011 Jones), external quantum efficiency (EQE ~ 173%) and rapid photoresponse (rise/fall time ~ 75/3 µs) significantly higher to an individual ReSe2 device (mobility = 36 cm2 V−1s−1, Ion/Ioff ratio = 1.4 × 105–1.8 × 105, R = 11.2 AW−1, D* = 1.02 × 1010, EQE ~ 26.1%, rise/fall time = 2.37/5.03 s). Additionally, gate-bias dependent Schottky barrier height (SBH) estimation for individual ReSe2 (45 meV at Vbg = 40 V) and Gr/ReSe2-HS (9.02 meV at Vbg = 40 V) revealed a low value for the heterostructure, confirming dry transfer technique to be successful in fabricating an interfacial defects-free junction. In addition, HS is fully capable to demonstrate an excellent gas sensing response with rapid response/recovery time (39/126 s for NO2 at 200 ppb) and is operational at room temperature (26.85 °C). The proposed Gr/ReSe2-HS is capable of demonstrating excellent electro-optical, as well as gas sensing, performance simultaneously and, therefore, can be used as a building block to fabricate next-generation photodetectors and gas sensors.

Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds’ adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced.

Fly ash (FA) is a waste product generated in huge amounts by coal-fired electric and steam-generating plants. As a result, the use of FA alone or in conjunction with other materials is an intriguing study topic worth exploring. Herein, we used FA waste in conjunction with titanium oxide (TiO2) to create (FA-TiO2) nanocomposites. For the first time, a cathodic polarization pre-treatment regime was applied to such nanocomposites to efficiently produce hydrogen from an alkaline solution. The FA-TiO2 hybrid nanocomposites were prepared by a straightforward solvothermal approach in which the FA raw material was mixed with titanium precursor in dimethyl sulfoxide (DMSO) and refluxed during a given time. The obtained FA-TiO2 hybrid nanocomposites were fully characterized using various tools and displayed a cenosphere-like shape. The synthesized materials were tested as electrocatalysts for the hydrogen evolution reaction (HER) in 0.1 M KOH solution in the dark, employing various electrochemical techniques. The as-prepared (unactivated) FA-TiO2 exhibited a considerable HER electrocatalytic activity, with an onset potential (EHER) value of −144 mV vs. RHE, a Tafel slope (−bc) value of 124 mV dec−1 and an exchange current density (jo) of ~0.07 mA cm−2. The FA-TiO2′s HER catalytic performance was significantly enhanced upon cathodic activation (24 h of chronoamperometry measurements performed at a high cathodic potential of −1.0 V vs. RHE). The cathodically activated FA-TiO2 recorded HER electrochemical kinetic parameters of EHER = −28 mV, −bc = 115 mV dec−1, jo = 0.65 mA cm−2, and an overpotential η10 = 125 mV to yield a current density of 10 mA cm−2. Such parameters were comparable to those measured here for the commercial Pt/C under the same experimental conditions (EHER = −10 mV, −bc = 113 mV dec−1, jo = 0.88 mA cm−2, η10 = 110 mV), as well as to the most active electrocatalysts for H2 generation from aqueous alkaline electrolytes.

Three mononuclear 2-picolylamine-containing zinc(III) complexes viz [(2-PA)2ZnCl]2(ZnCl4)] (Zn1), [(2-PA)2Zn(H2O)](NO3)2] (Zn2) and [Zn(2-PA)2(OH)]NO3] (Zn3) were synthesized and fully characterized. Spectral and X-ray structural characteristics showed that the Zn1 complex has a square-pyramidal coordination environment around a zinc(II) core. The hydroxide complex Zn3 was non-covalently functionalized with few layers of graphene oxide (GO) sheets, formed by exfoliation of GO in water. The resulting Zn3/GO hybrid material was characterized by FT-IR, TGA-DSC, SEM-EDX and X-ray powder diffraction. The way of interaction of Zn3 with GO has been established through density functional theory (DFT) calculations. Both experimental and theoretical findings indicate that, on the surface of GO, the complex Zn3 forms a complete double-sided adsorption layer. Zn3 and its hybrid form Zn3/GO have been individually investigated as electrocatalysts for the hydrogen evolution reaction. The hybrid heterogenized form Zn3/GO was supported on glassy carbon (GC) with variable loading densities of Zn3 (0.2, 0.4 and 0.8 mg cm−2) to form electrodes. These electrodes have been tested as molecular electrocatalysts for the hydrogen evolution reaction (HER) using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in 0.1 M KOH. Results showed that both GC-Zn3 and GC-Zn3/GO catalysts for the HER are highly active, and with increase of the catalyst’s loading density, this catalytic activity enhances. The high catalytic activity of HER with a low onset potential of −140 mV vs. RHE and a high exchange current density of 0.22 mA cm−2 is achieved with the highest loading density of Zn3 (0.8 mg cm−2). To achieve a current density of 10 mA cm−2, an overpotential of 240 mV was needed.

In the original publication [...]

This study aims to design a new nanocomposite as a supporting material for wiring the enzyme to develop a bioanode in the enzymatic biofuel cell (EBFC). In this work, polyaniline-based nanocomposite was synthesized by in situ polymerization of aniline monomer. The zeta potential study of the nanofillers was carried out, which reveals the interaction between the nanofillers. The synthesized nanocomposite (MWCNT/ZnS/AgNWs/PANI) was characterized by analytical techniques, such as Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction spectroscopy (XRD). Furthermore, the surface morphology and the in-depth information of the synthesized nanocomposite were displayed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. In addition, the as-synthesized nanocomposite and the designed bioanode underwent the electrochemical assessment using different electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV) for evaluating the electrochemical behavior of the fabricated anodes. The electrochemically regulated bioanode (MWCNT/ZnS/AgNWs/PANI/Frt/GOx) obtained an open-circuit voltage of 0.55 V and produced a maximal current density of 7.6 mA cm−2 at a glucose concentration of 50 mM prepared in phosphate buffer solution (PBS) (pH 7.0) as a supporting electrolyte at a scan rate of 100 mV s−1.

In this study, a high-density ZrN/ZrSi2 composite reinforced with ZrO2 as an inert phase was synthesized under vacuum starting with a Zr-Si4N3-ZrO2 blend using combustion-synthesis methodology accompanied by compaction. The effects of ZrO2 additions (10–30 wt%) and compression loads (117–327 MPa) on the microstructure, porosity and hardness of the samples were studied. The process was monitored using XRD, SEM, EDS, porosity, density and hardness measurements. Thermodynamic calculations of the effect of ZrO2 addition on the combustion reaction were performed including the calculation of the adiabatic temperatures and the estimation of the fractions of the liquid phase. The addition of up to 20 wt% ZrO2 improved the hardness and reduced the porosity of the samples. Using 20 wt% ZrO2, the sample porosity was reduced to 1.66 vol%, and the sample hardness was improved to 1165 ± 40.5 HV at 234 MPa.

In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (Tc), spin polarization, half magnetic ferromagnetism and transport properties of ZnX2Se4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of Tc is perceived for ZnCr2Se4. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) μB of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔEcrystal, exchange energies Δx(d), Δx (pd) and exchange constants (Noα and Noβ). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0–400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 1011 W/mK2) among studied compounds.

Light-driven heterogeneous photocatalysis has gained great significance for generating solar fuel; the challenging charge separation process and sluggish surface catalytic reactions significantly restrict the progress of solar energy conversion using a semiconductor photocatalyst. Herein, we propose a novel and feasible strategy to incorporate dihydroxy benzene (DHB) as a conjugated monomer within the framework of urea containing CN (CNU-DHBx) to tune the electronic conductivity and charge separation due to the aromaticity of the benzene ring, which acts as an electron-donating species. Systematic characterizations such as SPV, PL, XPS, DRS, and TRPL demonstrated that the incorporation of the DHB monomer greatly enhanced the photocatalytic CO2 reduction of CN due to the enhanced charge separation and modulation of the ionic mobility. The significantly enhanced photocatalytic activity of CNU–DHB15.0 in comparison with parental CN was 85 µmol/h for CO and 19.92 µmol/h of the H2 source. It can be attributed to the electron–hole pair separation and enhance the optical adsorption due to the presence of DHB. Furthermore, this remarkable modification affected the chemical composition, bandgap, and surface area, encouraging the controlled detachment of light-produced photons and making it the ideal choice for CO2 photoreduction. Our research findings potentially offer a solution for tuning complex charge separation and catalytic reactions in photocatalysis that could practically lead to the generation of artificial photocatalysts for efficient solar energy into chemical energy conversion.

The present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4′-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the reference compound to evaluate the efficiency of the remainder. In this respect, two structural factors were examined, namely, (i) the effect of replacement of the S-atom of diaryl sulfide by SO or SO2 group, (ii) the effect of the introduction of an electron-withdrawing or an electron-donating group in the aryl moiety. Two computational chemical approaches were used to achieve the objectives: the density functional theory (DFT) and the Monto Carlo (MC) simulation. First, B3LYP/6-311+G(d,p) model chemistry was employed to calculate quantum chemical descriptors of the studied molecules and their geometric and electronic structures. Additionally, the mode of adsorption of the tested molecules was investigated using MC simulation. In general, the adsorption process was favorable for molecules with a lower dipole moment. Based on the adsorption energy results, five diaryl sulfide derivatives are expected to act as better corrosion inhibitors than dapsone.

Cutting-edge technologies are making inroads into new areas and this remarkable progress has been successfully influenced by the tiny level engineering of carbon dots technology, their synthesis advancement and impressive applications in the field of allied sciences. The advances of science and its conjugation with interdisciplinary fields emerged in carbon dots making, their controlled characterization and applications into faster, cheaper as well as more reliable products in various scientific domains. Thus, a new era in nanotechnology has developed into carbon dots technology. The understanding of the generation process, control on making processes and selected applications of carbon dots such as energy storage, environmental monitoring, catalysis, contaminates detections and complex environmental forensics, drug delivery, drug targeting and other biomedical applications, etc., are among the most promising applications of carbon dots and thus it is a prominent area of research today. In this regard, various types of carbon dot nanomaterials such as oxides, their composites and conjugations, etc., have been garnering significant attention due to their remarkable potential in this prominent area of energy, the environment and technology. Thus, the present paper highlights the role and importance of carbon dots, recent advancements in their synthesis methods, properties and emerging applications.

The aim of this study was to improve the solubility of etoposide–ethylcellulose (ET–ETO) microparticles using the freeze-drying technique. Ethylcellulose (EC) microparticles loaded with etoposide (ETO) were prepared with different drug–polymer molar ratios of 1:1, 1:3, 1:6, and 1:20 by the solvent evaporation method. The size of the prepared microparticles was 0.088 µm. The results showed that the amount of ETO encapsulated into the microparticles was 387.3, 365.0, 350.0, and 250 µg/50 mg microparticles for microparticles with drug–polymer ratios of 1:1, 1:3, 1:6, and 1:20, respectively. The FT-IR spectra showed no chemical interaction between ETO and the polymer in the solid state. The results obtained from the dissolution experiment showed that the freeze-dried microparticles were stable in 0.1 N HCl (gastric pH) for 2 h. At pH 7.4, the ETO release was 60 to 70% within the first 15 min and approximately 100% within 30 min. Results from the application of different dissolution models showed that the equations that best fit the dissolution data for the ET–ETO microparticles at pH 7.4 were the Higuchi and Peppas model equations. The in vitro cytotoxicity assay of free ETO and freeze-dried microspheres prepared in this study with a drug–polymer ratio of 1:1 was performed in two mammalian cancer cell lines, MCF-7 (for bone cancer of the mammary organ) and Caco-2 (for mammalian epithelial colorectal adenocarcinoma). The results showed that the half-maximal inhibitory concentrations (IC50 values) for ETO and freeze-dried ET–ETO microparticles were 18.6 µM and 27.1 µM, respectively. In conclusion, freeze-dried ET–ETO is a promising formulation for developing a fast-dissolving form of ETO with a significant antiproliferative activity against the tested cell lines used in this study. It is a promising formulation for local duodenal area targeting.

Emergence of membrane technology for effective performance is qualified due to its low energy consumption, no use of chemicals, high removal capacity and easy accessibility of membrane material. The hydrophobic nature of polymeric membranes limits their applications due to biofouling (assemblage of microorganisms on surface of membrane). Polymeric nanocomposite membranes emerge to alleviate this issue. The current research work was concerned with the fabrication of sulfonated graphene oxide doped polyvinylidene fluoride (PVDF) membrane and investigation of its anti-biofouling and anti-bacterial behavior. The membrane was fabricated through phase inversion method, and its structure and morphology were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-rays diffraction (XRD) and thermo gravimetric analysis (TGA) techniques. Performance of the membrane was evaluated via pure water flux; anti-biofouling behavior was determined through Bovine Serum albumin (BSA) rejection. Our results revealed that the highest water flux was shown by M7 membrane about 308.7 Lm−2h−1/bar having (0.5%) concentration of SGO with improved BSA rejection. Furthermore, these fabricated membranes showed high antibacterial activity, more hydrophilicity and mechanical strength as compared to pristine PVDF membranes. It was concluded that SGO addition within PVDF polymer matrix enhanced the properties and performance of membranes. Therefore, SGO was found to be a promising material for the fabrication of nanocomposite membranes.

Tomato early blight, caused by Alternaria solani, is a destructive foliar fungal disease. Herein, the potential defensive roles of benzoic acid (BA) and two of its hydroxylated derivatives, ρ-hydroxybenzoic acid (HBA), and protocatechuic acid (PCA) against A. solani were investigated. All tested compounds showed strong dose-dependent fungistatic activity against A. solani and significantly reduced the disease development. Benzoic acid, and its hydroxylated derivatives, enhanced vegetative growth and yield traits. Moreover, BA and its derivatives induce the activation of enzymatic (POX, PPO, CAT, SlAPXs, and SlSODs) and non-enzymatic (phenolics, flavonoids, and carotenoids) antioxidant defense machinery to maintain reactive oxygen species (ROS) homeostasis within infected leaves. Additionally, BA and its hydroxylated derivatives induce the accumulation of salicylic acid (SA) and its biosynthetic genes including isochorismate synthase (SlICS), aldehyde oxidases (SlAO1 and SlAO2), and phenylalanine ammonia-lyases (SlPAL1, SlPAL2, SlPAL3, SlPAL5, and SlPAL6). Higher SA levels were associated with upregulation of pathogenesis-related proteins (SlPR-1, SlPR1a2, SlPRB1-2, SlPR4, SlPR5, SlPR6), nonexpressor of pathogenesis-related protein 1 (SlNPR1), and salicylic acid-binding protein (SlSABP2). These findings outline the potential application of BA and its hydroxylated derivatives as a sustainable alternative control strategy for early blight disease and also deciphering the physiological and biochemical mechanisms behind their protective role.

One of the most frequent ways to widen the adsorption range of carbon nitride (CN) is to add a well-known photosensitizer into its basic structure. So far, such attachments have been accomplished by using weak van der Waals forces. However, using strong covalent bonding to attach such photosensitizer with CN is yet to be determined. Here, for the first time, we covalently bonded porphyrin (5,10,15,20-tetrakis(4-(2,4-diamino-1,3,5-triazinyl) phenyl)-Porphyrin (TDP)), a renowned photosensitizer, effectively with CN by thermally balanced molecular strategy. A photoreaction system was set up for the deoxygenated conversion of CO2 to CO under visible light, where cobalt acted as a redox controller to speed up the charge transportation, while CN-TDP worked as a CO2 activating photocatalyst. The subsequent photocatalyst has a broader absorbance range, a greater specific surface area, and intramolecular organic connections that help to decrease the electron-hole pairs’ recombination rate. Furthermore, the average weight ratio between urea and TDP was well-tuned, resulting in a fantastic CO2 photoconversion for CN-TDP7.0 compared to the blank sample. This substantial increase in photocatalytic activity predicts a significant shift in CN’s specific surface area, band gap, chemical composition, and structure, as well as the efficient separation of photogenerated charge carriers from the ground state (HOMO) to the excited state (LUMO), making it a top candidate for CO2 photoreduction. At the same time, this approach paves the path for the bottom-up fabrication of carbon nitride nanosheets.

The molecular complexes between barbituric acid (BU) and chloranilic acid (ChA) over graphitic nitride (g-C3N4) are investigated. The molecular complexes and the nanocomposite were investigated both in solid state and in methanol. The solid complexes and the corresponding nanocomposite were investigated using FTIR, TGA, and UV-Vis spectroscopy. The structures were explored using DFT calculations using wB97XD/ and def2-TZVP basis set. The DFT calculations revealed the formation of hydrogen-bonded complexes, which initiate the proton transfer from ChA to BU. Immobilization of the BUChA complex over the g-C3N4 sheet was stabilized by weak non-covalent interactions, such as π–π interactions. g-C3N4 facilitated the charge transfer process, which is beneficial for different applications.

The agricultural use of organophosphorus pesticides is a widespread practice with significant advantages in crop health and product yield. An undesirable consequence is the contamination of soil and groundwater by these neurotoxins resulting from over application and run-off. Here, we design and synthesize the mononuclear zinc(II) complexes, namely, [Zn(AMB)2Cl](ClO4) 1 and [Zn(AMB)2(OH)](ClO4) 2 (AMB = 2-aminomethylbenzimidazole), as artificial catalysts inspired by phosphotriesterase (PTE) for the hydrolysis of organophosphorus compounds (OPs) and simultaneously detect the organophosphate pesticides such as fenitrothion and parathion. Spectral and DFT (B3LYP/Lanl2DZ) calculations revealed that complexes 1 and 2 have a square-pyramidal environment around zinc(II) centers with coordination chromophores of ZnN4Cl and ZnN4O, respectively. Both 1 and 2 were used as a modifier in the construction of a biomimetic sensor for the determination of toxic OPs, fenitrothion and parathion, in phosphate buffer by square wave voltammetry. The hydrolysis of OPs using 1 or 2 generates p-nitrophenol, which is subsequently oxidized at the surface of the modified carbon past electrode. The catalytic activity of 2 was higher than 1, which is attributed to the higher electronegativity of the former. The oxidation peak potentials of p-nitrophenol were obtained at +0.97 V (vs. Ag/AgCl) using cyclic voltammetry (CV) and +0.88 V (vs. Ag/AgCl) using square wave voltammetry. Several parameters were investigated to evaluate the performance of the biomimetic sensor obtained after the incorporation of zinc(II) complex 1 and 2 on a carbon paste electrode (CPE). The calibration curve showed a linear response ranging between 1.0 μM (0.29 ppm) and 5.5 μM (1.6 ppm) for fenitrothion and 1.0 μM (0.28 ppm) and 0.1 μM (0.028 ppm) for parathion with a limit of detection (LOD) of 0.08 μM (0.022 ppm) and 0.51 μM (0.149 ppm) for fenitrothion and parathion, respectively. The obtained results clearly demonstrated that the CPE modified by 1 and 2 has a remarkable electrocatalytic activity towards the hydrolysis of OPs under optimal conditions.

The effect of microstructure and chemistry on the kinetics of passive layer growth and passivity breakdown of some Ti-based alloys, namely Ti-6Al-4V, Ti-6Al-7Nb and TC21 alloys, was studied. The rate of pitting corrosion was evaluated using cyclic polarization measurements. Chronoamperometry was applied to assess the passive layer growth kinetics and breakdown. Microstructure influence on the uniform corrosion rate of these alloys was also investigated employing dynamic electrochemical impedance spectroscopy (DEIS). Corrosion studies were performed in 0.9% NaCl solution at 37 °C, and the obtained results were compared with ultrapure Ti (99.99%). The different phases of the microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Chemical composition and chemistry of the corroded surfaces were studied using X-ray photoelectron spectroscopy (XPS) analysis. For all studied alloys, the microstructure consisted of α matrix, which was strengthened by β phase. The highest and the lowest values of the β phase’s volume fraction were recorded for TC21 and Ti-Al-Nb alloys, respectively. The susceptibility of the investigated alloys toward pitting corrosion was enhanced following the sequence: Ti-6Al-7Nb < Ti-6Al-4V << TC21. Ti-6Al-7Nb alloy recorded the lowest pitting corrosion resistance (Rpit) among studied alloys, approaching that of pure Ti. The obvious changes in the microstructure of these alloys, together with XPS findings, were adopted to interpret the pronounced variation in the corrosion behavior of these materials.