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AISI 1045 medium carbon steel sheets having 10 mm thickness were subjected to the shielded metal arc welding process with three, five, and seven passes. The variations in the microstructure due to multiple thermal cycles in the heat-affected zone (HAZ), base metal (BM), and fusion zone (FZ) have been investigated and correlated with measured mechanical properties. Upon comparing fracture mechanics and mechanical properties with microstructural observations, it is elucidated that samples become ductile by increasing the number of thermal cycles which can be attributed to the transformations in the ferrite morphology in the HAZ. Based on mechanical, microstructural, and fracture analysis, it is concluded that post-weld heat treatment can be avoided if the number of passes during welding is increased.

It's crucial to fabricate commercial-level electrodes with high mass loading of active materials for supercapacitors (SCs) to address the growing need for commercial-level flexible energy storage devices. In this work, we reported the direct growth of ZnCo2O4 nanonest-like structure composed of nanowires with high mass loading (5 mg cm−2) on the substrate of carbon cloth (CC, hereafter denoted as ZnCo2O4@CC) via a simple hydrothermal method. The ZnCo2O4@CC electrode was characterized by a variety of techniques including SEM/TEM, XRD/XPS, and BET/BJH. The ZnCo2O4@CC electrode possesses a holey characteristic with various electroactive sites for the utilization of electrolyte and delivered high specific capacitance of 1467 (1320 C g-1) Fg−1 at 1.2 Ag-1 with outstanding cycling retention of 95% at 12 Ag-1 and high Coulombic efficiency after 10,000 cycles. In addition, we employed power's law to explore the charge storage kinetics of ZnCo2O4@CC electrode to investigate the capacitive and diffusion-controlled charge storage quantification. The ZnCo2O4@CC electrode displayed high capacitive storage properties (42% capacitive at 15 mVs−1). Thus, the admirable electrochemical performance of the ZnCo2O4 electrode highlights the potential application in supercapacitors for future endowers.

The development of smart structured cathode materials for supercapacitors (SCs) has sparked tremendous interest. However, the appropriate design to achieve high capacitance and energy density-based cathode materials remains a major problem for energy storage systems. This article describes the effective synthesis of self-supported 3D micro-flowers composed of ultrathin nanowires array of Co3O4 on Ni foam (NF) using hydrothermal conditions (Co3O4@NF). The mesoporous Co3O4@NF with a high surface area, providing a rich active state for the Faraday redox reaction and increasing the diffusion rate of the electrolyte ions. The optimized Co3O4@NF-16h electrode exhibited supreme electrochemical performance by delivering a high specific capacitance of 1878, (1127) and 1200 (720 C g−1) F g−1 at 1.0 and 20 A g−1, respectively. The Co3O4@NF electrode retained good capacitance stability of 91% over 10000 cycles at 20 A g−1 with excellent rate-performance of 67% at 20 folded high current values. The obtained results for the Co3O4@NF electrode are presented the enhanced pseudocapacitive performance, indicating the substantial potential for high-performance supercapacitor applications.

Manganese (Mn)-based oxides are considered suitable positive electrode materials for supercapacitors (SCs). However, their cycle stability and specific capacitance are significantly hindered by key restrictions such as structural instability and low conductivity. Herein, we demonstrated a novel nanorod (NR)-shaped heterostructured manganese dioxide/manganese selenide membrane (MnO

The shuttle effect and sluggish redox kinetics of polysulfides seriously hinder the potential application of lithium–sulfur (Li–S) batteries. Herein, distinctive hollow structures of NiS2 (NiS2/C HSs) are developed to establish a double barrier of physical and chemical adsorption to prevent the migration of polysulfides and effectively accelerate the conversion of sulfur, which are verified by both theoretical computations and experiments. Attributed to the unique morphology and superior electrocatalytic activity of NiS2/C HSs, batteries with NiS2/C HSs can deliver excellent performance with a reversible capacity of 634 mA h g−1 with 2.0 mg cm−2 sulfur loading after 1000 cycles at 1.0C, which corresponds to a slight capacity fading rate of 0.017% per cycle. This work offers a simple MOF-derived strategy for the synthesis of NiS2/C HSs, holding great promise in developing practical applications of Li–S batteries with high energy density.

It is of great significance to design electrochemical energy conversion and storage materials with excellent performance to fulfill the growing energy demand. Bimetallic cobalt/nickel-based electrode materials exhibit excellent electrical conductivity compared to mono oxides. However, their potential as electrode materials for high-performance supercapacitors (SCs) is limited because of their poor cycling stability and high-capacity fading. This work demonstrates the synthesis of binder-free bimetallic NiCo

This study presents a comparison among different-bottled drinking water commercially available in Lahore Pakistan. For that, five locally produced drinking water brands and four national brands were selected. Different physical, chemical and microbiological parameters like EC, pH, salinity, TDS, Na+, K+, Ca2+, Mg2+, Cl−, F−, Fe3+, SO42-, NO3-, PO43-, Arsenic (As), total coliforms and faecal coliforms/Escherichia coli were analysed . Results showed that there was a remarkable difference in the quality. Analysed data exposed that EC range was 141–298.3 μS/cm, pH 7.35–7.95, Salinity 0.1 ± 0.02 ppt, turbidity 2.13–2.45 NTU, TDS 85–182 mg/L, sodium 12–71.2 mg/L, potassium 0.1–2.4 mg/L, calcium 16–40 mg/L, mag- 30 magnesium 2.5–35 mg/L, chloride 35–95 mg/L, fluoride 0.29–0.94 mg/L,Iron below detectable limits to 0.17 mg/L, sulphate s 22–120 mg/L, phosphates 0.023–0.17 mg/L, nitrates 0.9–3.6 mg/L and arsenic were 0.0005–0.01 mg/L in these brands of drinking water. The analysed data was compared with the PSQCA, US–EPA and WHO standards. In only one brand of water, the concentration of sodium (71.2 mg/L) and arsenic (0.01 mg/L) was higher than permissible limits. For microbiological contamination brand E (80 colonies/100 mL sample), C (25 colonies/100 mL sample), S (100 colonies/100 mL sample) and K (15 colonies/100 mL sample) were .Some of these water brands examined were deficient in essential minerals like S brand in which Magnesium was only 2.5 mg/L and K and G brands in which calcium was 16 mg/L and 20 mg/L, respectively It was observed that treatment plants having raw water of low TDS 60 or those whose process based on 50% mineral dosing and 50% blending were cost-effective. Data presented in this study are important because it can be considered as baseline data for future.

Electrochemical and photo behavior of quaternary-layered Fe doped Ti3SiC2 (Fe-TSC) fabricated via in situ method with different SiFe contents after anodization was investigated through optical and electrical examinations for elucidating both the photo response behavior and energy storage mechanism. Results showed that Fe element was successfully doped into the Ti3SiC2 by in situ sintering. Then the anodized phase of Fe-TSC transformed into Fe doped TiO2 along with the significantly changed morphological shape from smooth intercalation structure to nanoporous layered structure by simultaneous chemical dissolution and oxidation. The dramatically enhanced photocurrent of 4.68 μA cm−2 and capacitor performance of 16.9 mF cm−2 for the anodized Fe doped Ti3SiC2 (Fe-ATSC) demonstrated that the superior composition and structure than the Fe-TSC. The enhanced visible light adsorption is attributed to the Fe doped TiO2 (Fe-TiO2) and the unique structure with diffusion channels to amplify the light efficiency and impede the recombination to prolong the life time of electrons/holes. The reinforced capacitive behavior refers to the nanoporous multilayer structure which encompasses abundant active energy storage. Moreover, the well electrochemical stability of the Fe-ATSC is evidenced by the capacitance which can retain 90.6% after 900 cycles.

In this work, iron oxide (Fe3O4) nanodiscs and anchored on reduced graphene oxide (rGO) as a nanocomposite (Fe3O4/rGO) have been fabricated through a surface, scalable hydrothermal process. The morphological and structural studies of Fe3O4/rGO nanodiscs are analyzed by various techniques such as XRD, XPS, SEM, TEM, and TGA, etc. The Fe3O4/rGO electrode is tested as a negative electrode in a basic potassium hydroxide (KOH) electrolyte using a three-electrode system for supercapacitor applications. The optimized electrochemical properties of Fe3O4/rGO are systematically compared with bare Fe3O4 and it is found that the rGO greatly enhanced its performance as a negative electrode. The Fe3O4/rGO nanodiscs demonstrated a notably high-specific capacitance of 1149 F/g at 1.5 A/g better than that of Fe3O4 nanodiscs (920 F/g at 1.5 A/g). Furthermore, the Fe3O4/rGO displays the superior cyclic stability of 97.53% after running continuous 10000 GCD cycles at a high current density of 10 A/g, while bare Fe3O4 attained 87.82% at identical conditions. The fascinating electrochemical performance can be benefited for future fabrications of iron graphene-based negative electrode material for SCs.

TiO2/γ-Al2O3 composite powder was prepared by the low-temperature hydrothermal synthesis in an alcohol solution without subsequent high-temperature calcination. When the as-prepared mesoporous γ-Al2O3 particles were added into the reaction solution, their surfaces with a negative potential were adsorbed by Ti(OH)4, forming mesoporous structure with the ink bottle type. These mesopores can absorb varisized organic molecules into their cavities, so that the mesoporous γ-Al2O3 is highly suitable for use as the adsorption and degradation material. Lots of oxygen defects formed during the synthesis process can hinder the recombination of the excited electrons and holes in TiO2. More free excited holes and electrons react with dissolved oxygen and water molecules in the solution to form the key functional groups of superoxide anion radicals (·O2−) and hydroxyl radicals (·OH), making the organic dye completely degrade to CO2 and H2O.

Herein, a crystalline nano-flowers structured zinc oxide (ZnO) was directly grown on carbon fiber textile (CFT) substrate via a simple hydrothermal process and fabricated with a binder-free electrode (denoted as ZnO@CFT) for supercapacitor (SC) utilization. The ZnO@CFT electrode revealed a 201 F·g−1 specific capacitance at 1 A·g−1 with admirable stability of >90% maintained after 3000 cycles at 10 A·g−1. These impressive findings are responsible for the exceedingly open channels for well-organized and efficient diffusion of effective electrolytic conduction via ZnO and CFT. Consequently, accurate and consistent structural and morphological manufacturing engineering is well regarded when increasing electrode materials’ effective surface area and intrinsic electrical conduction capability. The crystalline structure of ZnO nano-flowers could pave the way for low-cost supercapacitors.

In this manuscript, we have investigated the transport properties of Ag/Zn2GeO4/Si Schottky diode using temperature dependent current–voltage (I-V) characteristics. The ZnO sample was grown on Si substrate was fabricated by home developed thermal coating unit. The silver (Ag) metal contact of diameters 0.78 mm2 was fabricated on grown Zn2GeO4 and was studied comprehensively using pico meter over temperature range of 120 K–425 K. The I-V data demonstrated that ideality factor decreased from 6.2 to 2.0 and barrier height increased from 0.3 to 0.8 eV as the measurement temperature increased from 120 to 425 K respectively. The data demonstrated the presence of inhomogeneity at the interface of Ag metal and Zn2GeO4 semiconductor. To explain the barrier height inhomogeneity, we have further process the data by plotting different graphs between ideality factor versus barrier height and 1/2kT versus barrier height. The graph between ideality factor and barrier height gives a homogenous barrier height of 0.6 eV. Barrier height versus 1/2kT plot was drawn to obtain the values of mean barrier height for 0.75 eV and standard deviation (δs) 0.016 V at zero bias respectively.

Cost-effective, clean, highly transparent, and flexible as well as a coatable packaging material is envisioned to solve or at least mitigate quality preservation issues of organic materials, originating from moisture interaction under ambient conditions. Liquid phase processing of packaging coatings using nano-clay and polyvinyl alcohol (PVOH) has been developed and reported. Detailed analysis of the developed coating revealed moisture permeability of 2.8 × 10−2 g·cm/m2·day at 40 °C and 85% relative humidity (RH), which is in close accordance with Bharadwaj’s theoretical permeability model. Moreover, the developed coatings are not only more than 90% transparent, when exposed to white light, but also exhibit excellent flexibility and even after going through 10,000 bending cycles maintained the same blocking effect against moisture.

Oxygen vacancies were introduced into WO3-x under H2/Ar reduction atmosphere at high temperatures, accompanied by the change in morphology. The enhanced photocatalytic performance of WO3-x powders was systematically investigated. With the reduction temperature increasing, WO3 gradually transformed to the mixture of WO2.9, WO2.72 or WO2, while the corresponding morphologies changed from irregular particles to homogeneous nano-sheets and then to larger nano-rods. The nano-sheet sample containing WO2 and WO2.9 exhibits the optimum catalytic activity due to the special heterostructure. In this heterostructure, the conduction band electrons of WO2.9 can occupy the nearest valence band and subsequently combine with the adjacent internal holes in WO2, inhibiting the self-recombination of excited electron-hole pairs in WO2.9 to improve the photocatalytic properties.

A new composite gel polymer electrolyte (PEO-Bp-LATP) membrane consisting of poly-ethylene oxide (PEO), benzophenone (Bp) and varying amounts of highly ion-conducting lithium aluminum titanium phosphate (LATP) particles was prepared by significant Ultraviolet (UV) technology. The as-prepared PEO-Bp-LATP electrolyte membranes showed improved mechanical properties and superior electrochemical performances in Lithium metal batteries (LMBs). Typically, PEO-Bp-15 wt% LATP showed highest ionic conductivity (σ = 3.3 × 10−3 S.cm−1) at RT, a high Li-transference (tLi+ = 0.77 ) and wider electrochemical stability window (ESW) above 5 V as well as good mechanical strength (9.3 MPa). More significantly, the PEO-Bp-15 wt% LATP membrane has an excellent inhibitory effect on Li dendrite expansion in Li symmetric cells and presents a long term cyclic stability with current density of 2 mA/cm2 over 1100 h for Li//PEO-Bp-15 wt% LATP //Li. Our results for the measurement of galvanostatic charge-discharge deliver fascinating rate performance at 0.1C. Hence, the present study demonstrates that the UV-irradiated PEO-Bp-LATP membrane can be a promising electrolyte to meet the requirements for the next-generation LMBs.

Lithium batteries (LBs) have become increasingly important energy storage systems in our daily life. However, their practical applications are still severely plagued by the safety issues from liquid electrolyte, especially when the batteries are exposed to mechanical, thermal, or electrical abuse conditions. Gel polymer electrolytes (GPEs) are being considered as an effective solution to replace currently available organic liquid electrolyte for building safer LBs. This review provides recent advancements in GPEs applied for high-performance LBs. On the one hand, from the environmental and economic point of view, the skeletons of GPEs changed from traditional polymer to renewable and degradable polymer. On the other hand, in addition to being as a component with good electrochemical and physical characterizations, the GPEs also need to provide some functions for addressing the concerns of lithium (Li) dendrites, unstable cathode electrolyte interface, dissolution and migration of transition metal ions, “shuttle effect” of polysulfides, and so on. Finally, to synchronously meet the challenges from the advanced cathode and Li metal anode, the bio-based GPEs with multi-functionality are proposed to develop high-energy/power-density batteries in the future.

Compression tests of W-1.5ZrO2 alloy were carried out on a Gleeble-1500D thermal simulator at temperatures ranging from 1000 °C to 1400 °C and strain rates ranging from 0.01 to 1 s−1. The flow stresses, microstructure evolution and processing parameters optimization in different deformation conditions were investigated. The relationship between flow stress, strain rate and deformation temperature were also established based on the Arrhenius model. Furthermore, the law of activation energy and material constants with the variation of true strain was obtained in consideration of the strain influence. During hot deformation, the main restoration mechanism for W-1.5ZrO2 alloy was dynamic recrystallization (DRX) and dynamic recovery (DRV). DRV plays a dominant role in the high-temperature deformation of the W-1.5ZrO2 alloy. Partial DRX occurs in tungsten alloy when the temperature rises to 1400 °C, at the same time high temperature and low strain rate leads to the original grain growth. The obtained processing map of dynamic material modeling is used to analyze the deformation mechanism and the instability mechanism of the W-1.5ZrO2 alloy. For the strain of 0.5–0.6, the optimal processing parameters for the W-1.5ZrO2 alloy were in the temperature range of 1300 °C–1400 °C and strain rate range of 0.1–1 s−1.

Increasing concentration of carbon dioxide (CO2) in the atmosphere is responsible for global warming in the world. Up to date, many technologies have been investigated to reduce the concentration of CO2 in the environment but no technology has got significant successes yet. Recently graphene based membrane has attracted increasing attention for their potential applications in gas separation. In this review, we focus on separation of CO2 from gas mixtures through graphene-based membranes. More specifically, the separation of gas mixtures such as CO2/H2, CO2/CH4, CO2/N2 and CO2/O2 which have similar compositions in flue gas treatment, hydrogen purification and natural gas purification will be discussed. The advantages and disadvantages of these membranes will also be part of discussion and finally, the review ends with several recommendations and suggestions on the future prospect for CO2 separation. Keywords: Carbon dioxide, Global warming, Graphene, Membrane, Separation, Purification

A novel three-dimensional hierarchical ternary aerogel of TiO2 nanoparticles@porous carbon nanofibers-reduced graphene oxide (TiO2@PCNF-GA) was designed as an advanced anode for lithium-ion capacitors. TiO2@PCNFs were first fabricated by electrospinning assisted by carbonization and a post-etching process, and then assembled into reduced graphene oxide aerogels (GAs) to obtain the TiO2@PCNF-GAs. The uniform distribution of the ultrafine TiO2 nanoparticles in the PCNFs inhibits the aggregation of the TiO2 nanoparticles. Meanwhile, the interconnected three-dimensional network constructed from the TiO2@PCNFs and the GAs inhibits the aggregation of the TiO2@PCNFs. Moreover, the hierarchical porous structure of the TiO2@PCNF-GAs affords numerous Li-ion transport paths. Therefore, the lithium-ion capacitor composed of the TiO2@PCNF-GAs anode and an activated carbon cathode exhibits high energy density versus power density (79.7 Wh kg−1 versus 75 W kg−1, 15.0 Wh kg−1 versus 15 kW kg−1) with superior cycle stability (93.3% retention after 10000 cycles at 5.0 A g−1).

(1 − x)(Na0.5Bi0.5)TiO3–xBi(Mg2/3Nb1/3)O3 ceramics with x = 0.00 mol.% (0BMN), 0.01 mol.% (1BMN), 0.03 mol.% (3BMN), and 0.05 mol.% (5BMN) were synthesized using a solid-state processing technique. The thermogravimetric analysis (TGA) of uncalcined samples up to 730 °C showed that the maximum weight loss was observed for 3BMN, whereas the minimum weight loss was attributed to the 0BMN sample. After that, calcination was performed at 800 °C for 4 h. The XRD of calcined samples showed the successful formation of the perovskite phase with no impurity phases. 1BMN and 3BMN samples showed some of the lattice strain; however, a morphotropic phase boundary (MPB) existed around x = 0.03 between the rhombohedral and tetragonal structure. The TGA of the green pellets showed weight loss up to the sintering temperature (1100 °C) and during the 3 h holding period. 5BMN showed the maximum weight loss up to sintering temperature, as well as during the holding period, whereas 0BMN displayed the minimum weight loss up to sintering temperature, as well as some weight gain during the holding period. The relative permittivity (εr) was maximum at low frequencies, but the addition of BMN improved the εr. The frequency dependence of dielectric loss (tanδ) showed that the maximum loss was observed for 3BMN at lower frequencies, and 5BMN showed the maximum loss at higher frequency among all samples.

High energy-density supercapacitors (SCs) with long operating life, cost-effective, and competitive cycling performance is attracted great research attention to competing in the requirements of the modern age. However, despite these benefits, SC hampers inadequate rate-capability and structural deterioration, which primarily affects its commercialization. Herein, ultra-thin two-dimensional (2D) ZnCo

The highest specific capacity (3860 mAh g−1) and minimum negative electrochemical potential make lithium metal as a perfect candidate for next-generation high energy battery. However, the safety issue caused by the lithium dendrite growth hinders the practical use of lithium metal battery. Herein, a polymer/polymer-ceramic/polymer sandwich structure electrolytes (SWEs) are proposed to address this problem by combing the advantage of inorganic and gel-type polymer electrolytes. The flexible SWEs show a high ionic conductivity (~3.01 ×10−3 S/cm) at room temperature, high lithium transference number (tLi+ = 0.74), and stable electrochemical widows up to 5.0 V. Furthermore, the SWEs can effectively prevent lithium dendrites in a symmetric Li/SWEs/Li test during charge and discharge with a current density of 1 mA/cm2 for 240 h at room temperature. Meanwhile, the lithium metal battery assembled using LiCoO2/SWEs/Li exhibits the high cycling capacity of ~ 110 mAh g−1 at 2 C over 100 cycles and fascinating rate performance (144 mAh g−1@ 1 C and 98 mAh g−1@ 5 C) at room temperature. Our work provides a new design paradigm to exploit the advanced electrolyte for lithium metal battery and flexible devices.

A binder-free composite composed of two-dimensional (2D) vanadium oxysulfide nano-spindles (VoS-NS) directly grown on carbon textile (CT) substrate (VoS-NS@CT) is prepared as a novel electrode for high-performance pseudocapacitors (PCs). Benefiting from the merits of highly exposed active sites and enhanced electrical conductivity, optimized VoS-NS@CT exhibits remarkable specific capacitance of 1305 Fg−1 at 4 Ag−1 with superb retention of 97.7% after 15,000 cycles and possesses good rate capability. Furthermore, the VoS-NS@CT delivered high pseudocapacitive charge storage properties (80%, capacitive) at 15 mVs−1.

High energy-density supercapacitors (SCs) with long operating life, cost-effective, and competitive cycling performance is attracted great research attention to competing in the requirements of the modern age. However, despite these benefits, SC hampers inadequate rate-capability and structural deterioration, which primarily affects its commercialization. Herein, ultra-thin two-dimensional (2D) ZnCo2O4nanosheets arein situanchored on the conductive surface of nickel foam (denoted as ZCO@NF) by hydrothermal process. The binder-free ZCO@NF is employed as an electrode for SCs and shows impressive charge storage properties. ZCO@NF electrode exhibited a high capacitance of 1250 (750) and 733 F g-1(440 C g-1) at 2.5 and 20 A g-1, respectively, demonstrating the outstanding rate-capability of 58.6% even at 8 times larger current density. Furthermore, the ZCO@NF electrode exhibits admirable capacitance retention of 96.5% after 10 000 cycles. This impressive performance of the ZCO@NF electrode is attributed to the high surface area which gives a short distance for ion/electron transfer, a high conductivity with extensive electroactive cities, and strong structural stability. The binder-free approach provides a strong relationship between the current collector and the active material, which turns into improved electrochemical operation as an electrode material for SCs.

3D Porous manganese oxide nanorods (pMn-NRs) are produced via hydrothermal approach and utilized as an electrode material for pseudocapacitor. The pMn-NRs supported on carbon textile exhibit high pseudocapacitive charge storage in an aqueous electrolyte. Interestingly, the pMn-NRs electrode can operate up to a potential window of 1.0 V and exhibits admirable capacitance of 1243F g−1 at 1 A g−1 (approaching theoretical value) with superb cycling stability (98%) over 15,000 cycles.

The current study focused on the improvement of thermoelectric properties of Cu2ZnSnS4 (CZTS) thin films grown by the chemical solution method by our engineering other secondary phases. The density of copper mono-sulfides (CuS) related secondary phases was controlled by our varying the molar concentration of sulfur during the growth process. Data from thermoelectric studies suggested that the Seebeck coefficient, electrical conductivity, and power factor were increased from 148 to 393 μV/°C, from 18.51 to 76 S/cm, and from 4.05 × 10−5 to 1.17 × 10−3 W/m K2, respectively, as the concentration of sulfur atoms increased from 2 to 8 mM. This huge improvement in thermoelectric properties was linked to the development of CuS-based secondary phases due to extra sulfur atoms in the CZTS crystal. For verification of secondary phases, we used a number of characterization techniques, such as X-ray diffraction (XRD), conductivity measurements, Raman spectroscopy, photoluminescence spectroscopy, UV/vis spectroscopy, and scanning electron microscopy measurements. The XRD data verified the tetragonal structure of the CZTS thin films, and the crystalline size was found to decrease as the sulfur content increased. It is also demonstrated by the XRD data that CuS-based secondary phases started to develop for the samples with higher molar concentration of sulfur along with intensity reduction of the CZTS peaks. The vibrational modes of CZTS thin films were also confirmed by Raman spectroscopy with 288 and 334 cm−1 A1g, 350 cm−1 B (TO), and 367 cm−1 B (LO) lattice vibrational modes. However, the Raman peak intensity of sulfur-based secondary phases such as CuS, Cu2S CuxS, and Cu2-xS was found to increase with increasing concentration of sulfur. Scanning electron microscopy images of CZTS thin films showed that the sample prepared with a sulfur concentration of 8 mM has a rough surface as compared with samples prepared with a lower concentration of sulfur The UV/vis spectroscopy data suggest that the band gap of CZTS thin films decreased from 2.19 to 1.91 eV as the concentration of sulfur atoms increased from 2 to 8 mM. Photoluminescence measurements also supported our argument.

Highly flexible pseudocapacitors (PCs) have great potential in modern electronics such as portable and wearable devices. However, they are not yet mature enough to reach the market due to low energy density. In this study, for the first time, we are reporting an efficient synergetic approach by optimizing the feeding ratio of cobalt:gallium (Co:Ga) with a binder-free architecture composed by novel hexagonal-shaped nanoplates on carbon cloth (CC) substrate with high surface area to achieve high-energy electrode for asymmetric supercapacitor (ASC). Owing to the integrated strengths including enhanced electronic/ionic transportation and structural stability, the optimized sample with feeding ratio of Co:Ga = 1:2 (Co1Ga2O4@CC) electrode exhibited excellent charge storage performance, including high capacitance of 1525 F g−1 (915 C g−1) at 5 A g−1 with superb rate-capability and superior cycling stability of 95% up to 10000 cycles. The charge storage mechanism was analyzed using typical electroanalytical methods and ex-situ XPS analysis, which reveals the hybrid-type charge storage characteristics in the aqueous electrolyte. Furthermore, the all-solid-state flexible asymmetric supercapacitors (Co1Ga2O4@CC||AC@CC-ASC) were assembled and explored their energy storage properties. The Co1Ga2O4@CC||AC@CC-ASC shows good performance by achieving a high capacitance of 239 F g−1 (382 C g−1) at 1.5 A g−1 and can be operated at an extended potential window of 0.0–1.6 V. The Co1Ga2O4@CC||AC@CC-ASC also demonstrates interesting features such as light-weight (491.43 mg), ultra-thin (0.08 cm), high-energy and power densities (84 Wh kg−1, 1.85 Wh cm−3 at the power density of 1200 W kg−1, 26.4 W cm−3), and excellent flexibility. Our new approach, anchoring the CoGa2O4 hexagonal nanoplates on the highly flexible carbon cloth substrate, may provide useful insights into the reaction mechanism of high-energy electrode materials for prompting energy storage applications.

The magnetic ZnFe2O4 nanoparticles were synthesized and combined with carbon nanotubes (CNTs) to form a unique tangled structure (ZnFe2O4@CNT), and then used as wave absorbing functional nanofillers of polyvinylidene fluoride (PVDF) matrix. The effects of ZnFe2O4@CNT functional nanofillers on the microstructure, crystallization behavior and electromagnetic wave absorption properties of PVDF were studied. The ZnFe2O4@CNT/PVDF composite membranes containing 7 wt% nanofillers presented an optimal reflection loss of −54.5 dB with a sample thickness of 2.4 mm when the processing temperature was 60 °C. If the processing temperature of 150 °C was adopted, the composite membranes with a thickness of only 2.0 mm surprisingly achieved an effective absorption of the whole X-band. The combination of interfacial polarization, polarization relaxation loss, dipole polarization, conductivity loss, and ferromagnetic resonance loss promoted the excellent microwave energy dissipation capacity of ZnFe2O4@CNT/PVDF system.

A non-target analysis was developed for the analysis of extractables from multi-layer coextrusion bags exposed to 4% benzyl alcohol solution and 0.1 M sodium acetate at pH = 5 for defined periods (15 day, 45 day and 90 day) according to manufacturer instructions based on the ultra-performance liquid chromatography (UPLC) quadrupole-time of flight mass spectrometry (Q-TOF MS). In order to confirm the extractables, principal component analysis (PCA) was used to indicate the differences among samples of different periods. Then, the extractables were identified based on searching the self-built library or online searching. The total content of extractables of 90 day samples was 589.78 μg/L, and the content was in the range of acceptable levels for pharmaceutical manufacturers. The risk assessment of the extractables were evaluated by Toxtree and T.E.S.T. software to avoid the animals bioexperiment.