查看更多>>摘要：? 2022 Elsevier B.V.Long-term thermal stability is essential for the use of 6082 aluminium alloy in battery packaging. Precipitate coarsening and property changes in the alloy during 1000 h of thermal exposure at 100, 125, 150, and 175 °C were studied experimentally and theoretically. Variations of tensile properties were exhibited. The microstructural and nanoscale precipitates were characterized by microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Alloys exposed at 100 °C and 125 °C were thermally stable, retaining the strength above 340 MPa after a thermal exposure of 1000 h. Alloys exposed at 150 and 175 °C lost 25% and 48% of their respective strengths after 1000 h of exposure, reaching 253 and 178 MPa. Precipitates gradually increase in size with increasing thermal exposure time or temperature, while their number density decreases. After thermal exposure at 175 °C for 1000 h, the length of precipitates increased from 31 nm to 328 nm, and the coarsening rate of precipitates was 2.22 × 10?30 m3s?1. Comparing the experimental and theoretical coarsening rates showed that the Kuehmann–Voorhees (KV) model is suitable for calculating the precipitate coarsening rate of 6082 aluminium alloy. This study proposes a new method to predict the strength of aluminium alloy after thermal exposure; the effect of precipitate coarsening on alloy properties is also discussed quantitatively.
查看更多>>摘要：? 2022Supported Pt-based bimetallic catalysts are representative types of dehydrogenation catalysts used for alkanes to olefins conversion. The platinum in these catalysts exhibits unique structural features accompanied with changes in electronic states due to the addition of the second metal. To investigate the impact of each effect on the activity for propane dehydrogenation, a series of Pt-M/SiO2 (M= Fe, Cu, Ga, In and Sn) catalysts were prepared and used for propane dehydrogenation. Utilizing various characterization techniques, the geometric and electronic properties of these catalysts were studied. The relationships between the specific activity of bimetallic platinum catalysts in propane dehydrogenation and atomic sizes of alloys (i) and the total density of unoccupied d bands in platinum (ii) were considered. Via alloy formation, it was found that dilution of the active metal Pt occurred in these SiO2 supported bimetallic catalysts, and the lattice parameter of Pt-M alloys decreased on Pt-Fe, Pt-Cu and Pt-Ga alloys, but increased on Pt-In and Pt-Sn alloys when compared with that of Pt foil. Catalytic activity was evidently shown to not be a function of the lattice parameters of Pt-M alloys, but appears closely related with the D-holes of Pt in Pt-M bimetallic catalysts. More d holes show favorably high activity. Among the studied Pt-M/SiO2 (M= Fe, Cu, Ga, In and Sn) catalysts, the prominent and primary role of the electronic effect was demonstrated.
查看更多>>摘要：? 2022 Elsevier B.V.The spin dynamics, magnetic structures and magnetic anisotropy of single crystals PrxY1?xFe3(BO3)4 have been studied using antiferromagnetic resonance (AFMR) in a wide range of frequencies, magnetic fields, and temperatures. The frequency-field dependences of AFMR for the crystals with x = 0.25 and 0.45 are characteristic of antiferromagnets with the easy plane (EP) anisotropy. The crystals with x = 0.75 and 1.0 exhibit frequency-field dependences that are typical for antiferromagnets with the easy axis (EA) anisotropy. In these crystals, a significant decrease in the effective anisotropy fields of praseodymium upon the transition to the spin-flop state has been found. It is shown that this is the main reason for the large lability intervals, within which the regions of coexistence of the collinear and spin-flop states overlap. In the crystal with x = 0.67, the magnetic field applied along the trigonal axis of the crystal leads to the spin reorientation transition from the EA to the EP state. A magnetic phase diagram of the states on the plane “magnetic field - temperature” is built. In this crystal, the effective anisotropy field of praseodymium also decreases upon the transition to the field-induced EP state. Diamagnetic dilution of the praseodymium subsystem leads to the contribution of this subsystem to the total anisotropy field depending almost linearly on the praseodymium concentration.
查看更多>>摘要：? 2022 Elsevier B.V.Tin sulfide is considered as a promising semiconducting material for heterojunction solar cells in photovoltaic industry due to its suitable electrical and optical characteristics. Herein, we report a novel heterojunction tin sulfide (SnS)-based thin-film solar cell introducing cuprous oxide (Cu2O) as hole transport layer (HTL). Photovoltaic performances of the designed SnS solar device are evaluated by one-dimensional Solar Cell Capacitance Simulator (SCAPS-1D) program. The device outputs are assessed by varying thickness, carrier concentration, and defect density for the absorber. In addition, the thickness and doping density of HTL, defects at HTL/SnS and SnS/buffer interfaces, operative temperature, and work function of back contact are altered to evaluate the solar cell characteristics. Moreover, several HTLs including Cu2O, copper iodide (CuI), and nickel oxide (NiOx) are inspected to realize the outputs of suggested SnS solar device. The physical key parameters of the designed solar cell have been optimized to achieve excellent power conversion efficiency. The optimal thickness of the SnS absorber is found to be 1.0 μm for designing a highly efficient PV device. The conversion efficiency of 4.225% for the experimentally developed SnS-based thin-film solar structure without HTL is verified numerically. The efficiency of 29.68% with Voc = 1.01 V, Jsc = 34.19 mA/cm2, and FF = 85.74% is obtained numerically employing device parameters optimized for the proposed SnS solar cell with Cu2O HTL. These results suggest that the anticipated less-toxic Cu2O can be employed as a promising HTL to develop environmental friendly, low-cost, and highly efficient SnS thin-film heterojunction solar cell.
查看更多>>摘要：? 2022 Elsevier B.V.Owing to compositional advantages of the high theoretical capacity and 3D porous nanoarchitecture, the strategies for coupling of metal sulfide and metal-organic frameworks (MOFs) derived carbon materials have drawn considerable attention for high performance lithium storage. Herein, we present SnS decorated zeolitic imidazolate framework-8 derived ZnS/3D porous carbon composite (denoted as ZnS/PC) using the vacuum quartz capsule-assisted decoration method (denoted as ZnS/SnS/PC). In the composite, 3D-porous carbon could play the part of a conductive matrix as well as the buffer support for volume variation, while the decoration of ZnS/PC with SnS could provide abundant redox reactions, which could reinforce the storage properties and ions/electrons transfer driving force of ZnS/PC. Significantly, the synergistic coupling effect between the mixed metal sulfides and robust carbon matrix could further improve the electrochemical behavior. When compared with ZnS/PC anode for lithium-ion battery, ZnS/SnS/PC composite manifests obvious improvement in electrochemical performance for lithium storage, as well as appreciable lithium storage properties in a full lithium-ion battery.
查看更多>>摘要：? 2022 Elsevier B.V.Solid polymer electrolytes (SPEs) based solid-state lithium metal batteries (SSLMBs) are widespreadly practiced as one of the main technical routes aiming for chemically essential safety with acceptable energy density. However, uncontrollable Li dendrites growth and sluggish Li+ transport remain obstacles to the further development of SPEs-based SSLMBs. Herein, a porous g-C3N4 (PCN) is designed and introduced into polyethylene oxide (PEO). Within the following synthesized PEO-based composite solid electrolyte (PEO/PCN/LiTFSI CSE), PCN is found to be an attractive multifunctional filler. For its porous morphology and high specific surface area, abundant Lewis basic active sites are exposed, which facilitates Li+ to be uniformly distributed in PEO/PCN/LiTFSI CSE and thus more effectively mitigates the Li dendrites growth comparing to those with bulk g-C3N4 filler, making PCN-involved Li symmetrical cell (Li|PEO/PCN/LiTFSI|Li) run steadily for 1400 h under the current density of 0.1 mA cm?2 at 60 °C. PCN also accelerates Li+ transport in the manner of reducing PEO crystallinity and promoting LiTFSI dissociation. The Li+ conductivity of PEO/PCN/LiTFSI CSE reaches 3.47 × 10?4 S cm?1 at 60 °C. Therefore, long life span and high rate performances are together achieved in SSLMB assembled with PEO/PCN/LiTFSI CSE. This work reveals a feasible strategy to fabricate dendrite-free SSLMBs cycling within a fairly long time.
查看更多>>摘要：? 2022 Elsevier B.V.Transition metal dichalcogenides (TMDs) are one of the promising materials in the field of electronics and optoelectronics. The multifunctional TMD based nanocomposites such as WSe2-FeS2 can also become a potential candidate for these applications. In this work, WSe2-FeS2 nanocomposite thin films have been fabricated and studied for electrical transport and photoconductivity studies for the first time. Structural and optical analysis has been done, probing nanocomposite formation and defect states present in the deposited film. XPS analysis of WSe2-FeS2 shows solid interfacial bonding in the deposited films. Raman analysis shows the presence of E12 g mode for WSe2 and Eg, Ag, Tg modes for FeS2 and shift in Raman peaks corresponds to the disorder in the film. Also, the blue (red) shift of FeS2 (WSe2) PL emission probes the presence of defect/trap states. Temperature-dependent (173–350 K) resistivity results reveal the presence of more than one type of carrier transport mechanism - thermally activated conduction and hopping transport. The chalcogenide vacancies in WSe2-FeS2 affect the formation of trap states responsible for forming localized states. These localized states play a crucial role in the variable range hopping conduction at low temperatures. Whereas photoconductivity study yields a non-significant effect of light on photocurrent due to entrapment of carriers in trap states up to 250 K. Afterwards, a significant photocurrent increase was observed. The detailed mechanism considering all these aspects is explained in this work. It provides substantial new understandings for the carrier transport in WSe2-FeS2 nanocomposite thin films.
查看更多>>摘要：? 2022 Elsevier B.V.Recently, aqueous Zn/MnO2 batteries have attracted considerable attention due to their safety, low cost, and environmental friendliness. However, capacity decay caused by Mn dissolution greatly limits their further development. Herein, the synergistic effect of cathode passivation and electrolyte engineering was employed to widen the voltage window and improve the cycling stability of Zn/ε-MnO2 batteries. The cathode passivation process not only inhibits water decomposition at high voltage but also suppresses the Mn dissolution during discharge process. Meanwhile, the addition of LiTFSI in electrolyte can also effectively suppress the hydrogen evolution, significantly improving the Coulombic efficiency (CE) and stability of Zn stripping/plating processes. As a result, voltage window of 0.8–2.4 V is achieved and the dissolved Mn2+ ions are redeposited on the cathode at ≈ 2.2 V. The Mn2+-additive free Zn/ε-MnO2 battery maintains 80% capacity even after 300 cycles at 0.5 A g?1 and exhibits long term stability of more than 2000 cycles at 5.0 A g?1 with a specific capacity of 113 mAh g?1.
查看更多>>摘要：? 2022 Elsevier B.V.Recently, nanosized titanium oxides have attracted much attention for the technology of interfacial solar driven water evaporation (ISDWE). Various titanium oxides, such as TiO2 nanocage, Ti2O3 nanoparticle, and TiO2 nanotube, are favorable to provoke high water evaporation performance. In this work, ultrathin TiO2 nanosheets coated Ti plates were developed and applied on ISDWE. The ultrathin TiO2 nanosheet was obtained through hydrothermal treatment of Ti plate in aqueous NaOH solution, and C, N co-doping was realized through adding methionine in the solution. As the formation of nanosheet and C, N co-doping, the TiO2 nanosheets coated Ti plate exhibited enhanced solar light absorbility, water pumping ability, and specific surface area. Molecular dynamics simulations also indicated that the water-water and TiO2-water interactions can be weakened by C, N co-doping. Owning to the above reason, a notable high water evaporation rate of 1.57 kg?m?2?h?1 was achieved. Furthermore, the shape of Ti plate also affected the ISDWE performance, C, N co-doped TiO2 nanosheets coated square Ti plate showed a higher water evaporation rate than other shapes. Lastly, the enhanced photocatalytic activity of C, N co-doped TiO2 nanosheets coated Ti plate also enabled purification of unevaporated water and stable water evaporation rate during ISDWE experiment on RhB solution. This report highlights the advantages and potential of TiO2 nanosheet in the application of ISDWE on water purification.
查看更多>>摘要：? 2022 Elsevier B.V.The influence of mechanical stress on magnetization processes in an amorphous metal alloy have been investigated. The rapidly quenched amorphous metallic ribbons with nominal composition Fe73.5Cu1Nb3Si13.5B9 (precursor of FINEMET) were chosen for this study. The significant differences in the magnetic properties of the studied material were observed at different degrees of mechanical stress applied to the sample. The origin of these effects arises from changes in the dynamics of domain walls. They are primarily caused by variation of their fundamental properties (thickness, energy per unit area of the domain wall) as well as changes in the properties of internal stress areas, which are obstacles to their movement. Impact of stress areas was demonstrated by analysis of influence of mechanical load on the internal demagnetization factor.
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