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A new porphyrinic vanadium-based metal-organic framework (MOF), namely V-MOF-10 [V2(OH)2(H2TCPP)], constructed from {V(OH)O4}∞ chains and 4-tetracarboxyphenylporphyrin linkers, was synthesized by the solvothermal procedure. Structural analysis indicated that V-MOF-10 possesses the orthorhombic symmetry featured with two types of pores (5.2 × 11.9 A and 3.5 × 11.9 A). Full characterization of V-MOF-10 was analyzed by powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and elemental analysis (EA). N2 isotherm of V-MOF-10 at 77 K shows a reversible uptake and permanent porosity with a high BET (Langmuir) surface area of 1477 m2 g-1 (1553 m2 g-1). The optical band gap of V-MOF-10, measured by UV-Vis diffuse reflectance spectroscopy, is calculated to be 1.71 eV, resulting in a shift of absorption wavelength to the visible light region. Furthermore, our density functional theory (DFT) calculations confirm an acceptable correspondence of the band gap value with the mentioned experimental investigation, similar to the incorporated experimental and theoretical observations in the previous literature. Remarkably, V-MOF-10 exhibits an excellent photocatalytic property of organic dyes with the degradation efficiency of 100% for methylene blue (MB) and 89% for methylene orange (MB) after 120 min under illumination by visible light. These results suggest that V-MOF-10 could be used as a promising candidate in further photocatalytic studies.

In this study, facile solid-state CdS quantum dots (QDs) supported MoO3/g-C3N4 nanostructure photocatalysts were prepared via an innovative in-situ deposition protocol with consecutive ionic layer adsorption and reaction. The CdS QDs-anchored MoO3/g-C3N4 heterostructure photocatalysts demonstrated enhanced visible-light absorption capacity, which was realized by the quantum confinement of the CdS QDs. The maximum photocatalytic hydrogen (H2) production rate with the CdS QDs-anchored MoO3/g-C3N4 heterostructure photocatalysts reached 294.32 μmol g− 1 h−1, which was 76.84, 215.21, 27.12, and 3.64 folds superior as compare to bare g-C3N4, MoO3, CdS, and MoO3/g-C3N4 catalysts, respectively. The enriched photocatalytic performance was mainly credited to the high surface area and MoO3 with oxygen vacancies (OV), ultra-thin g-C3N4 and high optical adsorption ability of CdS QDs. Thus, forming a dual Z-scheme system in the CdS QDs-supported MoO3-OV/g-C3N4 nanostructures not only facilitated efficient interfacial charge transfer but also preserved the robust redox ability of the photoinduced electrons and holes.

Carbon steel coupons are used to characterize inhibition efficiency and surface properties for different Ficus racemosa leaf extract (FRLE) concentrations including 0, 500, 1000, 1500 and 2000 ppm in an aerated 0.1 M hydrochloric acid solution. The results indicate that carbon steel is significantly protected by FRLE and higher performances are reached with an increase in FRLE concentration up to 1500 ppm (93.11 ± 1.99%). Additionally, the addition of 2000 ppm FRLE reduced inhibition performance (88.86 ± 2.15%) due to high inhibition concentrations that could impede the formation of a solid protective film. This also demonstrates that the corrosion of steel is probably retarded via the formation of a protective film which is reinforced by FRLE concentration and exposure time due to the continuous adsorption of FRLE inhibitor components at suitable concentrations. The quantum chemical calculations demonstrate a high binding energy between FRLE molecules and carbon steel and a good thermal stability of the adsorbent layer, as well as an electron abundance of the FRLE species. This could result in a much more compact solid protective layer that could hinder electrochemical corrosion when carbon steel is exposed in an aerated 0.1 M hydrochloric acid solution.

Additive manufacturing not only offers the ability of constructing complex structural components but also creating strong and more durable parts than any other existing fabrication methods. In addition, it opens a novel research direction in developing new materials specifically for additive manufacturing beside the current wrought and cast materials. The present research attempted to produce an aluminum–magnesium–scandium alloy for selective laser melting. Nearly full dense samples were achieved through the process optimization. Significantly high mechanical strengths as-printed condition (450 MPa) with high ductility (26%) were obtained. This could be explained through super-fine and hierarchically graded microstructure and the formation of rod bundles in the melt-pool.

The integration of multi-dimensional functional materials of precious-metal-free semiconductor photocatalysts is of considerable significance for the conversion of solar energy to other forms of energy. Advanced materials for hydrogen-gas generation from water splitting using photonic energy have gained importance in modern science technology owing to the depletion of fossil fuels. In this study, an integrated ternary Na2Ti3O7/V2O5/g-C3N4 composite was prepared, and its performance in both hydrogen production from water splitting and organic-dye degradation was evaluated under visible-light illumination. Furthermore, the electrochemical behavior of Na2Ti3O7/V2O5/g-C3N4 was studied. The structural, morphological, and chemical properties of the prepared ternary composites were thoroughly analyzed through various analytical techniques. The ternary composite of Na2Ti3O7/V2O5/g-C3N4 exhibited admirable photocatalytic kinetics for H2 production and dye degradation, which was three times greater than that of Na2Ti3O7/V2O5. Moreover, the rate of RhB dye degradation by Na2Ti3O7/V2O5/g-C3N4 was higher than that of the Na2Ti3O7/V2O5 catalyst under identical conditions.

This work focuses on the formation of Ir3+ dopants in host TiO2 matrix to decrease the bandgap energy and a built-in electric field at the interface between Iro and TiO2. X-ray diffraction (XRD) re...

An oxygen-vacancy rich, bismuth oxide (Bi2O3) based MoS2/Bi2O3 Z-scheme heterojunction catalyst (2-BO-MS) was prepared in an autoclave hydrothermal method using ethanol and water. The performance of MoS2/Bi2O3 catalyst was examined for photocatalytic hydrogen evolution, photoelectrochemical activity, and crystal violet (CV) dye degradation by comparing with pristine Bi2O3 and MoS2. The hydrogen evolution performances of 2-BO-MS catalyst exhibited 3075.21 μmol g−1 h−1, which is 7.18 times higher than that of MoS2 (428.14 μmol g−1 h−1). The XPS, XRD and HRTEM analyses covered that the superior photocatalytic performance of 2-BO-MS catalyst might have stemmed out due to the existence of oxygen vacancies, enhanced strong interfacial interaction between MoS2 and Bi2O3 and specific surface area. The in-depth investigation has been performed for MoS2/Bi2O3 Z-scheme heterojunction using several characterization techniques. Moreover, the photocatalytic mechanism for hydrogen evolution and photodegradation were proposed based on trapping experiment results. This results acquired using MoS2/Bi2O3 Z-scheme heterojunction would be stepping stone for developing heterojunction catalyst towards attaining outstanding photocatalytic activity.

The application of the nanofluid is highly increased due to its high heat rate in the attendance of the magnetic field. In current investigation, CFD is employed to model the impact of the non-homogenous magnetic force on the heat performance of backward-facing step nanomaterial flow. Current attempt tries to investigate the influence of the variable magnetic source on the flow feature of the nanofluid stream in the backward-facing step model. To study this problem, a vertical electrical wire is chosen to produce non-homogenous magnetic field. In our model, 4 Vol% nanoparticles ( $${\text{Fe}}_{3} {\text{O}}_{4}$$ ) are added to pure water to attain nanofluid. To simulate the nanofluid in our work, the FVM technique is selected. Our results initially validated with experimental studies and good agreement is achieved. Inclusive parametric evaluation is made to find the impact of non-uniform magnetic field and inflow nanofluid velocity on the thermal efficiency of backward-facing step flow.. Our results show that local heat transfer could increase up to 300% with impose of such source. Moreover, the rising number of the magnetic sources could extensively enhance the thermal feature.

In the present research, outputs of numerical modeling of hybrid nanomaterial flow structure and thermal behavior were investigated and in-house code was implemented for simulation. Radiation terms and Lorentz force terms were included in mathematical model. Outputs demonstrate the flow structure and isotherm style with altering important parameters. Dependence of variables on Nu values was summarized in a new formula. More intensive convection should be accomplished with growth of buoyancy force and permeability. More smooth separation from the hot surface can appear with rise in permeability. Besides, it is worth mentioning that augmenting Da leads to easier nanopowder migration and thinner boundary layer generation.

The selective drug delivery system could be an excellent alternative to fight cancer and pathogens, due to its minimized negative consequences. Radiofrequency hyperthermia treatments are an innovative method attracting attention recently, which is based on heat destruction of cancer cells, using nanofluids. However, for an optimized treatment approach, several factors including thermal conductivity of bio-nanofluid should be studied. Current article investigates the role of Lorentz force on nanomaterial stream between two cylinders which are circular. Non-homogeneous model is utilized for simulating nanomaterial, and Runge–Kutta technique was applied to resolve ordinary differential equations. Moreover, the influence of Brownian motion on the nano-powders feature was studied. The influence of various active terms, such as Hartmann amount, aspect ratio, Re, Eckert number, thermophoresis, Schmidt number, and Brownian terms, is analytically surveyed. Based on obtained results, the amount of velocity increases when Re increases, whereas it decreases as Lorentz force grows. Furthermore, the temperature gradient increases when the value of magnetic field grows; however, it declines as the other terms increase.

Transportation of hybrid ferrofluid has been illustrated in the current article with the imposition of Lorentz forces. A numerical approach with the help of vorticity formulation was involved. Outputs demonstrate the opportunity to manage the thermal behavior with the magnetic field. As Lorentz force is imposed, the strength of eddies reduces and velocity of nanopowders reduces. Reductive impact of Hartmann is ignorable in the lower permeability, but it becomes stronger with the rise in Da. As Rd enhances, isotherms become more disturbed and higher Nu is obtained. Unfavorable effect of permeability on the thickness of boundary layer makes Nu to increase, and a similar impact was demonstrated for buoyancy force.

Enhancement of the mixing inside the combustor is a significant process for increasing the efficiency of the scramjet. This work applied the computational method for the investigation of the depth of the cavity on the flow feature of the multi hydrogen jet in the supersonic crossflow. The main focus of this research is to evaluate the depth of the cavity on the mixing rate of the hydrogen jets inside the combustion chamber. CFD method with the SST turbulence technique is applied for the simulation of the fluid flow inside the domain. The impact of the depth of the cavity, the pressure of the fuel jet and the number of the jet are comprehensively explained in this study. Our findings show that the rising of the cavity enhances the mixing inside the domain due to more fuel distribution along the spanwise direction. Our results clearly demonstrate that replacing the single jet with 8 equivalent multi jets increases the mixing rate of more than 45% in the vicinity of the jet injection. Attained results revealed that increasing the jet space develops the mixing in far downstream. Obtained results also show that mixing intensifies 15% when jet space of 8 microjets is increased from 4 dj to 10 dj.

Electrical sensor has been considered in the current attempt. Combination of buoyancy, electric and radiative forces has been included in the governing equations. Convective flow attenuation with insertion of electric field and such force permits to control the style of the flow. Outputs have been illustrated in terms of contours and distributions. The increment of Nu corresponding to increasing permeability is less than that obtained with the rise of voltage. Nu increases with rise of shape factor which is attributed to easier nanoparticles transportation. Growth of radiation term makes Nu to augment, and impact of voltage become stronger.

Designing an efficient hybrid structure photocatalyst for photocatalytic decomposition and hydrogen (H2) evolution has been considered a great choice to develop renewable technologies for clean energy production and environmental remediation. Enhanced charge transfer (CT) based on the interaction between a noble metal and a semiconductor is a crucial factor influencing the movement of photogenerated electron-hole pairs. Herein, we focus on the recent advances related to plasmon-enhanced noble metals and the semiconductor nature to drive the photocatalytic H2 production and photodegradation of the organic dye rhodamine B (RhB) under UV and visible light irradiation. Specifically, the combination of concerted catalysis and green nanoengineering strategies to design ZnO-based composite photocatalysts and their decoration with metallic Ag have been realized by the radio frequency (RF) sputtering technique at room temperature. This simultaneity enhances the interface coupling between Ag and ZnO and reduces the energy threshold. The creation of charge transfer in the heterojunction and Schottky barrier changes the photoelectronic properties of the as-synthesized Al-doped ZnO (AZO); afterward, these effects promote the migration, transportation, and separation of photoinduced charge carriers and enhance the light-harvesting efficiency. As a result, the as-synthesized AZO-20 hybrid nanostructure exhibits a photocurrent density of 2.5 mA/cm2 vs Ag/AgCl, which is improved by almost 12 times compared with that of bare ZnO (0.2 mA/cm2). The hydrogen evolution rates of AZO-20 were ∼38 and ∼24 μmol/h under UV and visible light exposure, which are almost five- and tenfold higher than those of pristine ZnO, respectively. Additionally, the RhB degradation efficacies of the obtained AZO-20 were greater than almost 97 and 82% under UV and visible light illumination, respectively. The achieved apparent rate constant for the photocatalytic RhB decomposition was 0.014 min-1, indicating that it is 14-fold than that in pristine ZnO (0.001 min-1). Heterostructure AZO photocatalysts possess excellent practical stability in the water-splitting reaction and photocatalytic RhB decomposition, posing as promising candidates in practical works for pollution and energy challenges.

The usage of the nanomaterial inside the base fluid for hydrothermal enhancement has augmented in various devices and instruments. Though, several works are done to study the hydrodynamic of the nanofluid in different models and problems. In this current study, analytical approach is used to reveal the influence of nanomaterial on MHD flow in non-parallel plates. Homotopy perturbation method (HPM) is recently applied as reliable techniques for solving the nonlinear governing equations of the engineering problems. This study applied HPM as well as numerical technique of a fourth-order RK4 to ensure the validity of the results. Parametric research is done to find the effect of nanofluid fraction, Hartmann number and geometry angle on velocity profiles. According to our findings, hydraulic boundary layer thickness drops with growth of Re and it rises as Ha augments.

Simulation of swirl flow intensification with the use of new device inside a pipe was performed in the current investigation. To improve the feature of testing fluid, hybrid nanopowders were dispersed. Outputs were exhibited in terms of contours. Tangential velocity of nanomaterial augments with the increase in Re, and stronger convective mode is obtained with the rise in Re. Thinner thermal boundary layer close to the wall is an output of reducing pitch ratio and leads to greater Nu. Augmenting contact surface area with a decline in pitch ratio leads to stronger secondary flow.