This study comprehensively investigates the impact of various parameters on aluminum matrix composites (AMCs) fabricated using the powder metallurgy (PM) technique. An Al-Cu matrix composite (2xxx ...series) was employed in the current study, and Al2O3 was used as a reinforcement. The performance evaluation of the Al-4Cu/Al2O3 composite involved analyzing the influence of the Al2O3 weight percent (wt. %), the height-to-diameter ratio (H/D) of the compacted samples, and the compaction pressure. Different concentrations of the Al2O3 reinforcement, namely 0%, 2.5%, 5.0%, 7.5%, and 10% by weight, were utilized, while the compaction process was conducted for one hour under varying pressures of 500, 600, 700, 800, and 900 MPa. The compacted Al-4Cu/Al2O3 composites were in the form of cylindrical discs with a fixed diameter of 20 mm and varying H/D ratios of 0.75, 1.0, 1.25, 1.5, and 2.0. Moreover, the machine learning (ML), design of experiment (DOE), response surface methodology (RSM), genetic algorithm (GA), and hybrid DOE-GA methodologies were utilized to thoroughly investigate the physical properties, such as the relative density (RD), as well as the mechanical properties, including the hardness distribution, fracture strain, yield strength, and compression strength. Subsequently, different statistical analysis approaches, including analysis of variance (ANOVA), 3D response surface plots, and ML approaches, were employed to predict the output responses and optimize the input variables. The optimal combination of variables that demonstrated significant improvements in the RD, fracture strain, hardness distribution, yield strength, and compression strength of the Al-4Cu/Al2O3 composite was determined using the RSM, GA, and hybrid DOE-GA approaches. Furthermore, the ML and RSM models were validated, and their accuracy was evaluated and compared, revealing close agreement with the experimental results.
The hexagonal close-packed (HCP) crystal structure of Mg alloys lead to poor formability as well as other undesirable mechanical behaviors in an otherwise highly sought-after alloy for commercial ...use. This study investigates the evolution of microstructure, texture, corrosion and mechanical behaviors in Mg–Zn–Mn (ZM31) alloy after processing using Equal Channel Angular Pressing (ECAP). Dynamic recrystallization was evident in the ECAP-processed samples, correlated with a substantial fiber structure, and resulted in the attainment of notable grain refinement and high lattice strain. Average grain sizes of 2.2 and 2 μm were achieved via 2 and 4-Pass Bc processing, respectively. This significant refinement yielded lower corrosion rates through enhancement of the thickness, coherency, and stability of formed protective oxide layers. The corrosion rate in the NaCl medium was substantially enhanced by 99.5% after four passes via route Bc. The recrystallized fine structure was found to have contributed to yield strength, ultimate strength, and microhardness improvements. Deformation enhanced yield and ultimate strengths by 132% and 64%, respectively. The distinctive grain refinement mechanism exhibited through the current ECAP procedure has potential to pave the way for novel and impactful utilizations of ZM31 in industries that demand exceptional mechanical and corrosion performance.
Commercial pure Mg specimens were processed through equal channel angular pressing (ECAP) using two dies with die angles of 90° and 120°. Mg billets were processed up to four passes via different ...route types. Machine learning (ML) techniques were adopted to estimate the ECAP parameters and verify the experimental findings. Several ML techniques were employed to estimate the effect ECAP parameters of pure Mg on microstructural evolution, Vicker’s microhardness (HV), and tensile properties for ECAP billets and their as-annealed (AA) counterparts. Electron back-scatter diffraction (EBSD) was applied to determine the structural evolution and crystallographic texture both prior to and following the ECAP process for the Mg billets. EBSD analysis showed that route Bc is the most effective route in grain refinement, and four passes of route Bc experienced a significant refinement of 86% compared to the AA condition. Furthermore, the crystallographic texture showed that four passes of route Bc produced the most robust texture that was greater than 26.21 times random. ML findings revealed that the grain size demonstrated a strong correlation of −0.67 with rising number of passes, while ϕ affected the grain size strongly with 0.83. When adopting a 90°-die to accumulate the plastic strain up to 4Bc, the subsequent HV was indeed 111% higher than that of the AA equivalent. From ML findings it was clear that the number of passes was the most significant parameter on the Mg HV values, while ECAP channel angle (ϕ) revealed high correlation factor with HV values as well. Furthermore, four passes of route Bc with ϕ = 90° and 120° led to a significant increase of the tensile strength by 44.7%% and 35.7%, respectively, compared to the AA counterpart. ML findings revealed that the tensile strength was affected by the increasing number of passes with a strong correlation of 0.81, while affecting ductility moderately with 0.47.
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•CoPC was successfully immobilized on carbon cloth using assisted sonodeposition.•CoPc-CC electrode production reached 96% at −0.9 V vs. RHE for CO2-to-CO.•CoPc-CC catalyst retains ...its selectivity without no sign of degradation.•Heterogenizing molecular catalysts through sonodeposition is an effective way for robust electrodes.
CO2 reduction to carbon neutral fuels requires selective and well-designed catalysts. Herein, we report the cobalt phthalocyanine on carbon cloth (CoPc/CC) for CO2-to-CO electroreduction in water (pH = 7.2). The CoPc was immobilized using sono-deposition method. The sono-immobilized CoPc (noted sono-CoPc/CC) exhibited a high selectivity for CO production over a wide range of potentials from −0.5 to −0.9 V vs. RHE. Interestingly, The CO faradaic efficiency is over 80 % in the studied potentials range. The conversion efficiency to CO production reached 96% at −0.9 V. The CoPc/CC catalyst retains its selectivity without no sign of degradation for 10 h of electrolysis. This paper gives a new trend to heterogenized molecular catalysts on carbon supports.
ZnFe2O4 as an anode that is believed to attractive. Due to its large theoretical capacity, this electrode is ideal for Lithium-ion batteries. However, the performance of ZnFe2O4 while charging and ...discharging is limited by its volume growth. In the present study, carbon-coated ZnFe2O4 is synthesized by the sol–gel method. Carbon is coated on the spherical surface of ZnFe2O4 by in situ coating. In situ carbon coating alleviates volume expansion during electrochemical performance and Lithium-ion mobility is accelerated, and electron transit is accelerated; thus, carbon-coated ZnFe2O4 show good electrochemical performance. After 50 cycles at a current density of 0.1 A·g−1, the battery had a discharge capacity of 1312 mAh·g−1 and a capacity of roughly 1220 mAh·g−1. The performance of carbon-coated ZnFe2O4 as an improved anode is electrochemically used for Li-ion energy storage applications.
Laser-induced graphene (LIG) has attracted extensive research as an electrode material for micro-supercapacitors (MSC). However, the low capacitive performance of LIG arising from both limited ...specific surface area and few active sites remains challenging. Herein, in situ doping of fluorine and boron atoms into laser-induced graphene was innovatively achieved via laser direct writing approach using boron-doped fluorinated polyimide (FB-PI) as the precursor. The porous fluorine and boron co-doped laser-induced graphene (FB-LIG) exhibits more active sites and improved wettability and significantly enhanced capacitive performance due to the synergistic effect of fluorine and boron co-doping. By tuning the weight ratio of boron to fluorine, the MSC utilizing FB-LIG as the electrode and poly(vinyl alcohol) (PVA)/H2SO4 as the gel electrolyte delivers a high areal capacitance of 49.81 mF/cm2 at a current density of 0.09 mA/cm2, 23 times higher that of MSC from commercial polyimide (PI)-based LIG, and 3 times that of MSC from fluorinated PI-based LIG. In addition, MSCs from FB-LIG possess excellent mechanical stability and flexibility, rendering them promising for flexible wearable microelectronics.
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•In-situ doping of F/B is achieved by laser direct writing process.•The prepared F/B co-doped porous graphene has high specific surface area and abundant active sites.•The synergistic effect of F/B resulted in a high areal capacitance of 49.81 mF/cm2.
•As a superior electrode for use in energy storage applications, we have synthesized The Decoration of Sea-Urchin-Like NiCoP Coated With WSe2@ZnS As An Advanced Electrode Material For Hybrid ...Supercapacitors using the hydrothermal approach described in our current work.•The targeted hybrid supercapacitor electrode consists of NiCoP/WSe2@ZnS and has a high specific capacity of approximately 2,416 Fg−1 at 1 Ag−1. Moreover, it has shown excellent cycling stability, retaining 96% of its capacity after 5000 cycles.•NiCoP/WSe2@ZnS are employed as the positive electrode and activated carbon (AC) is used as the negative electrode in the asymmetric supercapacitor.•The manufactured asymmetric supercapacitor has a power density of 1064 Wkg−1 and a maximum energy storage capacity of 46.4 Whkg−1.
The manufacture of creative, efficient, and effective electrodes for use in energy storage systems is an ideal solution to the energy crisis. As a superior electrode for use in energy storage applications, we have synthesized Nickel cobalt phosphate (NiCoP) that has been covered with WSe2@ZnS using the hydrothermal approach described in our current work. The targeted hybrid supercapacitor electrode consists of NiCoP/WSe2@ZnS and has a high specific capacity of approximately 2,416 Fg−1 at 1 Ag−1. Moreover, it has shown excellent cycling stability, retaining 96% of its capacity after 5000 cycles. NiCoP/WSe2@ZnS is employed as the positive electrode and activated carbon (AC) is used as the negative electrode in the asymmetric supercapacitor. This permits the device to have a capacitance of 178 Fg−1 at a current density of 0.5 mAg−1. The manufactured asymmetric supercapacitor has a power density of 1064 Wkg−1 and a maximum energy storage capacity of 46.4 Whkg−1. Because of its outstanding electrochemical properties, metal phosphate will soon be recognized as a novel and attractive active material with potentially useful in energy storage applications.
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•Fluorinated Iron Porphyrin (FeFPor) electrocatalyst was successfully prepared.•Immobilized FeFPor on carbon cloth gave a high selectivity for CO in a wide potential range.•NaHCO3 was ...the best bicarbonate catalytic medium.•Highest conversion efficiency OF CO production reached 97% at −0.49 V vs. RHE.
The electrochemical CO2reductionreaction to form valued by-products is a challenging and a sustainable process. In general, CO2 reduction to carbon neutral fuels requires selective and well-designed catalysts. Herein, we report perfluorinated iron porphyrin (FeFPor) for CO2-to-CO electroreduction in different bicarbonate electrolytes, byproducts distribution in lithium, sodium, potassium and cesium were analyzed. The immobilized FeFPor on the carbon microporous layer of the carbon cloth exhibited a high selectivity for carbon monoxide production over a wide range of potentials from −0.5 to −1 V vs. RHE in all bicarbonate solution with the NaHCO3 being the best catalytic medium. The highest conversion efficiency to CO production reached 97% at −0.5 V vs. RHE in 0.5 M NaHCO3 in near neutral aqueous solution (pH = 7.2). The CO electrosynthesis dropped when using lithium, potassium and cesium bicarbonates, which was due to the CO2 concentration and reactions at the inner electrode-solution reactions.
Supercapacitor technology is a promising development in energy storage devices. Despite its potential as an anode material, nickel sulfhide (Ni3S2) utilization for practical application in energy ...storage devices is limited owing to its weak conductivity. Subsequently, it can be improved in the alteration of electronic properties by the introduction of impurities and surface defects. In this work, sulphur vacancy was created in hydrothermally synthesized nickel sulphide by inserting neodymium ions. The synergetic action of the dopant and produced sulphur vacancy have an effect on the electronic properties. The electrocatalytic behavior of the fabricated materials was also enhanced by adding polyethylene glycol, which was used as a reducing agent to promote the formation of sulphur vacancy. Examine the impact of neodymium doping concentration in nickel sulphide on the enhanced electrical structure of nickel sulphide by comparing electrocatalytic materials doped with varying amounts of neodymium. One of the 0.3-Nd doped nickel sulphide (0.3-NdNS) electrodes showed the best electronic properties, with a specific capacitance (Cs) of 2122.64 F g−1 at 1 A g−1 and energy density of 119.25 Wh Kg−1. The practical potential of the symmetric nature of 0.3-NdNS electrode material was examined with two electrode systems, exhibiting the specific capacitance (Cs). Our results suggest optimized 0.3-NdNS electrode materials have great potential for supercapacitor applications.
