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Although surfactants have been proved to be effective in controlling the size and morphology to prepare high-quality two-dimensional (2D) MOF nanosheets, the impact of surfactants remaining on the 2D MOF nanosheets on their microenvironment is rarely reported. In this paper, polyvinylpyrrolidone (PVP) was used as surfactant to synthesize Co-TCPP(Pd) (abbreviated as Co-Pd) nanosheets, and the content of PVP attached to Co-Pd nanosheets was controlled by ethanol treatment, to regulate the microenvironment around Co-Pd nanosheets. The XRD, FT-IR, XPS, TEM, and TG were used to confirm that after ethanol ultrasonic treatment, the PVP content on Co-Pd nanosheets was gradually reduced without damaging the original structure and morphology of Co-Pd nanosheets. PVP attached to Co-Pd nanosheets will slow down the electron migration rate, affecting the microenvironment around co-catalyst Pd, which has been confirmed by EIS, PL and DFT etc. The results exhibited that the Co-Pd-6 obtained by ethanol ultrasonic treatment 6 times showed the more excellent photocatalytic hydrogen evolution activity (8284.25 umol·g−1·h−1), which was 4.02 times as that of Co-Pd-0 (2059.59 umol·g−1·h−1) without ethanol ultrasonic treatment), indicating that PVP will have a negative impact on the microenvironment around the co-catalyst, thereby affecting the photocatalytic hydrogen evolution performance. This study indicates that efficient photocatalytic hydrogen evolution can be achieved via adjusting the microenvironment around the co-catalyst to promote electron transfer. • Ultra-thin Co-Pd nanosheets integrate photosensitive TCPP and cocatalyst Pd. • The effects of surfactants on the microenvironment around the active center were studied. • DFT confirmed the negative effects of PVP on the microenvironment around the active center. • Ethanol treatment showed excellent photocatalytic hydrogen evolution activity and stability. [ABSTRACT FROM AUTHOR]

As one of the most commonly used binary alloys, the effect of intermetallic compounds (IMCs) of Al-Cu alloys in powder metallurgy on their structure and properties is instructive for tailoring Al-Cu alloys for different applications. In this investigation, a series of Al-Cu-Ag alloys with varying Cu compositions were fabricated via hot pressing. TEM analysis identified CuAl 2 as the primary intermetallic compounds, with Ag existing in forms including Ag 2 Al, elemental Ag, and an Ag-(Cu) solid solution. The modulation of Cu content influenced the state of Ag and the mechanical behaviors of the Al-Cu-Ag alloy. Particularly, the high Al/Cu alloy, benefiting from a synergistic effect comprising stacking faults, nanoscale precipitates, and solid solutions, exhibited outstanding mechanical properties. Conversely, the Al-50Cu-3Ag alloys displayed significant brittleness, attributed to the adverse impact of large-scale intermetallic compounds and increased grain size due to the formation of CuAl 2. The incorporation of nanoparticles effectively mitigated the grain size in high Al/Cu alloys. This study elucidates the correlation between the evolution of intermetallic compounds and composition in Al-Cu alloys, offering novel insights into the reinforcement of both Al-based and Cu-based alloys. • The effect of IMCs of Al-Cu alloys on their structure and properties is instructive for tailoring Al-Cu alloys for different applications. • Changes in Cu content can greatly affect the properties of intermetallic compounds, and the morphology of Ag. • High Al and high Cu content Al-Cu-Ag alloys attributed to the effect of Orowan strengthening and stacking fault formation. • Massive formation of IMCs leads to mechanical behavior of Al-50Cu-3Ag alloys that similar to ceramics. [ABSTRACT FROM AUTHOR]

This study aimed to improve the corrosion resistance of Mg alloys, and to this end, AZ31 Mg alloy was subjected to laser surface re-melting using a fiber laser. Subsequently, a comparative analysis was conducted on the microstructures of the re-melted surfaces under various laser power settings, and the influence of laser surface re-melting on corrosion characteristics was investigated through a potentiodynamic polarization test. The test results show that laser surface re-melting produced a distinct reduction in the crystallite size of magnesium, ranging from 11.23–15.80 μm within the laser-melted layers. The maximum melted layer thickness of 820 μm was achieved with a laser power of 2100 W. The process of laser surface re-melting notably heightened the hardness, particularly as the power increased, which was attributed to swift solidification. The most noteworthy hardness measurement of 92.1 HV 0.02 was recorded at 2100 W. Thus, the study shows that laser surface re-melting significantly enhances the corrosion resistance of Mg alloys, primarily owing to the formation of a corrosion product. The smaller grain size on the surface contributes to the formation of a dense product film. [Display omitted] • The surface grain size of magnesium alloy decreases with the decrease of laser remelting power. • The surface remelting process can eliminate internal dislocations and reduce crystal defects. • Laser surface remelting induces the strengthening effect by refining the grains and the second phase particles. • After laser remelting treatment, the corrosion rate decreases, resulting in enhanced corrosion resistance. [ABSTRACT FROM AUTHOR]

N ickle (Ni)-rich layered oxides as promising candidate of high-capacity cathode materials have aroused extensive concern primarily regarding their higher specific capacity. However, the major hurdle of Ni-rich cathodes (Ni content ≥0.7) is their poor cycling stability, which often suffers from the release of oxygen, structural degradation and increased impedance during cycling, especially at high voltage or high temperature. Herein, we demonstrated a feasible solid phase method for easy industrialization based on the Al3+/Zr4+ co-doping in LiNi 0.72 Co 0.05 Mn 0.23 O 2 (A X Z Y -NCM) single-crystal cathode. The optimized A 0.5 Z 0.5 -NCM single-crystal material exhibited greatly enhanced structural and thermal stability. XRD refinement results indicated that both Al3+ and Zr4+ were mainly located in transition metal (TM) sites, strengthening the layered structure through strong M-O bonds and inhibiting cation mixing. In-situ XRD revealed that the synergistic rivet effect of Al/Zr co-doping alleviates anisotropic lattice stress-strain during charge/discharge process. Accordingly, the A 0.5 Z 0.5 -NCM cathode can output a high initial capacity of 177.3 mAh g−1 at 1 C, and captured a more desirable capacity retention of 85.10 % than that of U-NCM (74.33 %) at 1 C over 200 cycles. Even at a high voltage of 4.5 V, its capacity retention can still reach 82.37 %, significantly surpassing the unmodified U-NCM (31.0 %). The above results demonstrated that well-designed dual doping is highly effective for strengthen structure stability and cycling performance of Ni-rich cathodes. [Display omitted] • Al/Zr doped LiNi 0.72 Co 0.05 Mn 0.23 O 2 are designed to reveal the synergistic effect of Al/Zr co-doping on boosting structural stability. • The optimized A 0.5 Z 0.5 -NCM achieves the superior thermal stability with their thermal runaway temperature (229.69 oC). • The A 0.5 Z 0.5 -NCM shows excellent cycling stability with 85.1% retention after 200 cycles at 2.8∼4.35 V. [ABSTRACT FROM AUTHOR]

Na super ionic conductor (NASICON)-type Na 3 Zr 2 Si 2 PO 12 (NZSP) electrolytes, with their excellent safety and high energy density, are a promising candidate material for all-solid-state sodium-ion batteries. However, poor sintering performance and interfacial issues have limited its practical application. Herein, we propose the addition of sintering aids to densify grain boundaries and fine-tune the grain to achieve the densest microstructure, improve interfacial contact with sodium, and realize stable Na plating/stripping cycles at room temperature. (CuO) 2 -(B 2 O 3) 3 (CBO) is selected to reinforce grain boundary densification, inhibit dendrite growth, and ensure interfacial stability upon sintering at the lower temperature of 1000 °C. The optimized NZSP-0.2CBO demonstrates an ion conductivity reaching 6.83×10−4 S cm−1 at room temperature, exhibiting a lower activation energy of 0.27 eV compared to bare NZSP. The interface impedance of Na/NZSP-0.2CBO (34.48 Ω cm²) is significantly lower than that of bare NZSP (373.43 Ω cm²). The corresponding Na/NZSP-0.2CBO/Na exhibits stable deposition/stripping cycles over 850 h at 0.1 mA cm−2 and room temperature, with a low polarization voltage of 65 mV. These superior performances can be attributed to the densification effect that enhances conductivity, enabling a uniform and enhanced Na+ flux across the electrode/electrolyte interface without dendrite formation. A Na/NZSP-0.2CBO/Na 3 V 2 (PO 4) 3 battery is assembled accordingly, exhibiting a capacity of 87.4 mAh g−1for 100 cycles with a capacity retention rate of 84.9 % and a high average coulombic efficiency of 97.6 % at room temperature. [Display omitted] • CBO is the newly discovered sintering additive for the Na super ionic conductor (NASICON)-type Na 3 Zr 2 Si 2 PO 12 (NZSP). • CBO promotes densification and seals grain boundaries from electrons to maintain the interface stability of Na/ NZSP. • The lower interface impedance and the enhanced Na+ flux of Na/NZSP-0.2CBO contribute to this notable cycling stability. [ABSTRACT FROM AUTHOR]

In recent years, Sn(IV)-based inorganic-organic metal halides and their doped compounds have attracted much attentions due to their excellent luminescence properties and good stabilities. However, their concrete performance in materials and devices still strongly depends upon the organic molecular structure and relevant mechanisms. Here, a series of Sb3+-doped 0D Sn(IV)-based halides (C 20 H 20 P) 2 SnCl 6 :x% Sb were synthesized by the antisolvent vapor diffusion technique, showing improved luminescence properties and wavelength-dependent emission character. (C 20 H 20 P) 2 SnCl 6 :20% Sb3+ exhibits an efficient warm white emission, which possesses dual bands at 481 and 637 nm with a photoluminescence quantum yield (PLQY) of 99.2%, at the 320 nm excitation. Moreover, it also gives efficient orange-red emission band at 637 nm with PLQY of 97.1% at the 365 nm excitation. In this 0D Sn(IV) compound, Sb doping tends to form [SbCl 5 ]2-, whose high-energy emission band at 481 nm is from the self-trapped exciton (STE) out of the Sb singlet, and low energy orange-red emission band at 637 nm from the STE out of the Sb triplet. The latter is also accompanied with a DAP (donor-acceptor pair) transition between neighbouring SbCl 5 and SnCl 6 clusters. Their tunable and bright emission and excellent stability of (C 20 H 20 P) 2 SnCl 6 :20% Sb suit for a single-component WLED with warm white light emission as well as an information encryption system as shown. [Display omitted] • A series of 0D Sb3+-doped Sn(IV)-based halides (C 20 H 20 P) 2 SnCl 6 :x% Sb was synthesized. • Both the orange-red emission and warm white emission of (C 20 H 20 P) 2 SnCl 6 :20% Sb have near-unit PLQY. • The incorporated Sb3+ show with five coordination number due to the electronegativity difference between Sb(III) and Sn(IV). • The as-prepared powders show potential applications in solid state lighting and information encryption. [ABSTRACT FROM AUTHOR]

Two-dimensional materials have emerged as potential electrodes for lithium-ion storage, attributed to their adjustable band gap, abundant active sites, and efficient ion/electron transport properties. In this study, we synthesized Sb 2 Si 2 Te 6 with layered structures via mechanical alloying and subsequent annealing, investigating its suitability as an anode material for lithium-ion batteries. We employed polyacrylonitrile (PAN) pyrolysis to encapsulate Sb 2 Si 2 Te 6 in an amorphous carbon layer, resulting in the decomposition of Sb 2 Si 2 Te 6 into Sb 2 Te 3 , Si and Te (denoted as Sb-Si-Te@C composite). This composite electrode exhibited excellent cycling stability, maintaining 505.6 mAh g−1 after 200 cycles (92.2% capacity retention), and enhanced rate performance compared to uncoated Sb 2 Si 2 Te 6 , which showed only 98.7 mAh g−1 after 200 cycles (33.1% capacity retention). Furthermore, the electrode expansion rate was significantly curtailed to 80.6% for Sb-Si-Te@C, compared to 174.3% for Sb 2 Si 2 Te 6 after 100 cycles. This reduction indicates that the amorphous carbon layer enhances electron transfer during charging and discharging, effectively mitigating the electrode volume changes associated with cycling. These results underscore the potential of two-dimensional Sb 2 Si 2 Te 6 -derived composites as a promising anode material in lithium-ion batteries. • Two-dimensional silicon-based materials, Sb 2 Si 2 Te 6 , were obtained via solid-state reaction. • An amorphous carbon layer was coated onto Sb 2 Si 2 Te 6 through polyacrylonitrile pyrolysis. • The electrochemical performance of Sb-Si-Te@C composite anodes for lithium-ion batteries was investigated for the first time. • The Sb-Si-Te@C composite anode exhibited long cycling stability and high-rate performance. [ABSTRACT FROM AUTHOR]

Silicon has much higher theoretical specific capacity than traditional graphite materials (3579 mAh g−1 vs. Graphite: 372mAh g−1). However huge volumetric expansion (∼300%) of silicon seriously reduces its cyclic stability as anode in lithium-ion batteries. Though reduce the size of silicon based composites to nanoscale and tuning their porosity have been extensively studied, above strategies reduce the vibration density of the anode material unsurprisingly, which is not conducive to the advantage of high volumetric capacity anode. In this work, we design a unique graded silicon/carbon powder to maintain excellent energy storage performance at high vibration density. The composite of graded structure is constructed by first particles and second particles. The construction strategy is proved to be adoptable to achieve cost effective production of high performance silicon/carbon composite anode for development of advanced lithium-ion battery. Under the premise of industrial powder materials' production technologies, a graded structure silicon/carbon composite with optimized synthetic condition shows high-reversible capacity of 827.4 mAh g−1 at 200 mAh g−1 (equal to 1464.5 Ah L−1) and it capacity remains at 715.0 mAh g−1 after 800 cycles, with a capacity retention rate of 86.37%, which shows high cycle life. • Composite of silicon/carbon is prepared via industrial compatible processing methods. • It could be easily scaled up without limitation. • Graded structure makes it of high capaciatance, stability and initial coulombic efficiency. • Embedding silicon into volumetric variation tolerable carbon matrix is crucial to achieve above properties. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction (NRR) is regarded as a promising alternative to traditional Haber-Bosch process for ammonia (NH 3) production. Transition metal tellurides (TMTs) are believed to possess advantageous properties for NRR, but the related investigations remain lacking, let alone the comparison of their NRR catalytic activities under the identical conditions. Herein, a series of single-phase TMTs nano-/micro- materials were prepared by one-step hydrothermal method, including NiTe 2 NRs, Cu 7 Te 4 NPs, ZnTe MPs, Ag 2 Te NWs, CdTe NPs and Bi 2 Te 3 NSs, which were identically evaluated as NRR electrocatalysts in 0.1 M HCl. The most optimal FE of 26.3% and NH 3 yield rate of 43.8 μg h–1 mg cat. –1 are achieved at −0.4 V vs. RHE for NiTe 2 NRs, which are superior to other TMTs samples and the most of recently reported transition metal chalcogenides based electrocatalysts. [Display omitted] • A series of single-phase TMTs nano-/micro- materials were prepared by one-step hydrothermal method. • The NRR catalytic performances of TMTs samples were evaluated under the identical conditions. • The most optimal FE of 26.3% and NH 3 yield rate of 43.8 μg h–1 mg cat. –1 were achieved at −0.4 V vs. RHE for NiTe 2 NRs. [ABSTRACT FROM AUTHOR]

The role of lithium in hydrogen embrittlement (HE) and trapping of Al-Cu-Li alloys were investigated in experimental and density functional theory (DFT) calculations. The tensile curves and fracture morphology show that the Li-contained samples are more sensitive to HE than the Li-free samples and the HE sensitivity increases with the aging time expansion. The Transmission Electron Microscope (TEM) analyses reveal that the number density of T 1 (Al 2 CuLi) precipitates increases about 66.8% with aging process, suggesting that HE sensitivity is exacerbated by T 1 precipitates. In addition, the lithium in T 1 precipitates, solid solution matrix and solute segregation grain boundaries (GBs) always has a high affinity to hydrogen according to DFT calculations, where T 1 precipitates have the highest hydrogen trapping energy with 0.736 eV/H atom. Moreover, the influence of hydrogen on Al-Cu-Li alloys was investigated using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and electrochemical corrosion analysis. These analyses indicate that hydrogen exists in the form of hydrogen atoms, which results in a reduction in corrosion potential (E corr) from −676.3 mV to −699.3 mV by approximately 20 mV and an increase in corrosion current density (i corr) from 2.1×10−6 A/cm2 to 10.8×10−6 A/cm2 by an order of magnitude. The accumulated hydrogen atoms eventually lead to corrosion pits and blisters on the surface of alloys. [Display omitted] • The Li-contained alloys are more sensitive than the Li-free alloys to hydrogen embrittlement (HE). • The hydrogen trapping energy of T 1 precipitates is higher than those of other in DFT calculations. • The trapped hydrogen atoms decrease the surface corrosion resistance and lead to the corrosion pits and cracks. • The interactions between hydrogen and lithium intensify the transformation of the ductile to brittle fracture. [ABSTRACT FROM AUTHOR]

CdS Quantum dots (QDs) anchored onto the surface of MOF-808 (hereafter designated as CdS QDs@MOF-808) were constructed by solvothermal method and applied for degradation of ciprofloxacin (CIP) under visible light irradiation. The impacts of pH values and initial concentrations of CIP on adsorption and photocatalytic activity were explored in detail. The as-prepared CdS QDs@MOF-808 composites showed enhanced synergistic adsorption capacity and photocatalytic properties, especially for the CM-20 sample with 20 % CdS QDs loading exhibiting about 5.2 times adsorption capacity (130 mg/g) and approximately 5.5 times photocatalytic removal rate (82 %) for CIP compared with the pristine CdS and MOF-808. Various techniques such as XPS, UV‐vis DRS, Zeta potential, EIS, PL as well as transient photocurrent responses have demonstrated that the synergistic effect of CdS QDs and MOF-808 is ascribed to the enhanced electrostatic interactions and Zr-S forces, improving the utilization of visible light and effectively photogenerated electrons transported from the conduction band of CdS to that of MOF-808. Gas chromatography-mass spectroscopy (GC-MS) was used to detect the possible intermediates in the degradation process of CIP. [Display omitted] • CdS QDs@MOF-808 composites were constructed by solvothermal method and applied for degradation of ciprofloxacin (CIP). • The impacts of pH values and initial CIP concentrations on adsorption and photocatalytic activity were explored in depth. • The CM-20 with 20% CdS QDs loading exhibits excellent adsorption and photocatalytic properties. • The GC-MS was used to analyze the possible intermediates in the degradation process of CIP. [ABSTRACT FROM AUTHOR]

To attain superior electrochemical performance, a new series of high-entropy double perovskites are investigated as cathodes for solid oxide fuel cells. In this study, three PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5 double perovskites with different dopings of La, Pr, Sm, Gd, Nd, Y elements in A-site, high-entropy oxides (HEOs) cathodes are successfully prepared by EDTA-citrate combustion method and used as potential cathodes for SOFC at intermediate temperature. Three HEOs cathodes all form single phase double perovskite structure and match chemically well with Gd 0.2 Ce 0.8 O 2-δ (GDC) electrolyte. Linear thermal expansion coefficient of (La 0.2 Pr 0.2 Sm 0.2 Gd 0.2 Nd 0.2)Ba 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5 (LPSGNBSCF) at 200–1000 °C range is found to be moderate, 18.39 × 10−6 K−1. Typical anode supported SOFC with LPSGNBSCF cathode exhibits an excellent output performance of 1000 mW cm−2 with a lower polarization resistance of 0.3 Ω cm2 at 800 °C. These results might suggest that LPSGNBSCF can be a potential excellent cathode for SOFC. • High entropy PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ cathodes with A-site dopings are prepared. • SOFC with LPSFNBSCF cathode exhibits output performance of 1000 mW cm−2 at 800 °C. • LPSGNBSCF can be a potential cathode for SOFC. [ABSTRACT FROM AUTHOR]

The effects of Si and Cu doping on crystal structures, magnetism, and the magnetocaloric effect of EuAl 4 have been investigated. EuAl 4 , EuAl 3.35 Si 0.65 , and EuAl 3.82 Cu 0.18 single crystals grown by the Al flux method are isotypic and crystallize in BaAl 4 -type structure with space group I 4 /mmm. Compared to the pristine compound EuAl 4 , the lattice parameter a keeps almost unchanged and c decreases obviously by Si doping, while a decreases and c increases upon Cu-substitution. These irregular changes in the lattice parameters may contribute to the electronegativity difference between Si and Cu. Cu and Si doping enhances the ferromagnetic interaction, and the direction of easy magnetization changes from the ab plane to the c axis upon the Cu-substitution. Multiple-step metamagnetic transitions are still observed in EuAl 3.35 Si 0.65 as applying the magnetic field along the c axis, while EuAl 3.82 Cu 0.18 shows ferromagnetic behavior along the ab plane and c axis. As a consequence, the low-field magnetocaloric effect is significantly enhanced. The maximum magnetic entropy change under a field change of 20 kOe increases from − 8.4 J/kg K for EuAl 4 to − 12.9 J/kg K for EuAl 3.35 Si 0.65 and − 15.9 J/kg K for EuAl 3.82 Cu 0.18. The corresponding values of refrigerating capacity are 67, 140, and 147 J/kg, respectively. The remarkable magnetocaloric performances suggest that the Cu-doped EuAl 4 compound is an excellent candidate material for low-temperature magnetic refrigeration. • The doping of Si and Cu leads to the contraction of cell volume in EuAl 4 compounds. • Cu substitution enhances the ferromagnetism, and changes the direction of easy magnetization from the ab plane to c axis. • Large low-field magnetocaloric effect is acquired in Cu-doped EuAl 4 single crystal. [ABSTRACT FROM AUTHOR]

Recently, para -aramid nanofiber separators have attracted more attention in lithium metal batteries (LMBs); however, the balance between safety and electrochemical performance remains challenging. Herein, a robust, porous, and thermotolerant separator (ZPBIA) is proposed based on electrospun heterocycle aramid nanofibers and in-situ grown metal-organic framework (MOF). First, introducing H 2 SO 4 enables improved electrospinnability of rigid-chain poly(p-phenylene -benzimidazole-terephthalate) (PBIA) due to hierarchical hydrogen bonds crosslinking network formation. Next, zeolitic imidazolate framework-67 (ZIF-67) nanosheets anchored in situ on PBIA nanofibers confer high porosity (91%) and good electrolyte wettability to the ZPBIA separator. As a result, the assembled LFP/ZPBIA/Li cell with a high LiFePO 4 (LFP) loading (12 mg cm−2) delivers excellent rate capacity at 5.0 C (76 mAh g−1) and impressive long-term cycling stability at 1.0 C (a minor capacity decay of 0.031% per cycle after 500 cycles). Benefiting from the intrinsic properties of PBIA, the ZPBIA separator possesses high mechanical strength to prevent Li dendrites puncture. Moreover, the open circuit voltage stabilizes at ∼3.4 V from 30 to 150 ℃ for LFP/ZPBIA/Li cell, which is probably applied in high-temperature conditions. This work provides a novel fabrication of functional separators to balance the safety and electrochemical property of LMBs. [Display omitted] • The electrospun heterocyclic aramid nanofibers were prepared for the first time. • Hierarchical hydrogen bond network enhances the electrospinnability of H-aramid. • ZIF-67 in-situ modified H-aramid nanofiber separator was prepared. • The ZPBA separator possesses high porosity and excellent mechanical strength. • LIBs with ZPBIA separator shows superior rate and long-term cycle performance. [ABSTRACT FROM AUTHOR]

Rational designing Mo-based heterojunction catalysts as hydrogen evolution catalysts is seriously significant for the widespread utilization of hydrogen energy. Here, the ingenious hierarchical construction of MoP 2 /MoS 2 nanowires was delivered with high conductivity of porous MoP 2 and abundant active sites of defect-rich MoS 2. Under synergistic effect of two materials, this catalyst achieves a dramatically optimized electronic structure to boost hydrogen evolution in all-pH range. The optimal MoP 2 /MoS 2 /CC nanoreactor showed overpotentials of 47.11, 60.16, and 89.83 mV to drive −10 mA cm−2 and Tafel slopes of 51.69, 52.04, and 73.79 mV dec−1 in acidic, alkaline, and neutral media, respectively. This finding may provide an effective approach for elevating the pH-universal electrocatalytic performance in order to achieve industrial hydrogen evolution. • Delicate hierarchical construction of MoP 2 /MoS 2 lead to favorable preformace for HER. • High-dose thiourea hydrothermal prepares defective MoS 2 with plentiful active sites. • Porous semimetallic MoP 2 frame accelerates electron transport. • The MoP 2 /MoS 2 showes tiny overpotentials and robust stability over a wide pH range. [ABSTRACT FROM AUTHOR]

MnO attracts increasing attention as a lithium-ion battery anode material due to large theoretical capacity and relatively low cost, but its highly instable structure and low conductivity severely plague cycling stability. In addition to improved performance, easy preparation is also important for the development of MnO anode, and hence both of these aspects need attention. Toward this end, herein, a high-performance MnO-based anode material, composed of carbon coated porous nanoclusters assembled from smaller secondary Fe-doped MnO nanoparticles (denoted as Fe-MnO@C), has been prepared through a facile route. The findings demonstrate that the combination of Fe doping and carbon coating enables Fe-MnO@C to have higher structural stability and faster electrochemical kinetics than MnO and MnO@C counterparts. As a result, Fe-MnO@C anode shows outstanding lithium storage performances, maintaining 1038.4 and 512.3 mAh g−1 at 200 and 1000 mA g−1 after 320 and 400 cycles, respectively. Finally, this work not only offers a feasible method for improving MnO anode performance, but also gives a constructive reference for designing facile methods to prepare other advanced metal oxide-based anode materials. [Display omitted] • Dual modification strategies of Fe doping and carbon coating of MnO were achieved simultaneously. • This way offered MnO improved structural stability and electrochemical kinetics. • The as-prepared Fe-MnO@C anode exhibited long life and high capacity. • The findings gave a constructive reference for improving other metal oxide anodes. [ABSTRACT FROM AUTHOR]

The structural dimensions of the materials and the design of the components are important factor to optimize the electromagnetic wave (EMW) absorption. Herein, Ni nanoparticles and nitrogen-doped carbon-based composites (Ni@NC/NCNTs) were successfully synthesized under high-temperature carbonization by introducing dicyandiamide (DCDA) into flake-assembled flower spherical Ni-based metal-organic framework (Ni-MOF). The influence of the composition and structure of Ni@NC/NCNTs on the absorption properties of EMW are revealed by changing the carbonization temperature. It could be found that the Ni@NC/NCNT-600 composite exhibits a good absorption capacity in the C-band (4–8 GHz). At a filler loading of 30 wt%, its optimal reflection loss (RL) is −34.22 dB at 4.88 GHz. In addition, the effective absorption bandwidth (EAB) of 4.2 GHz could be obtained at 1.8 mm. And Ni@NC/NCNT-1000 composite also achieve the same bandwidth at thin thicknesses (1.21 mm). The reasonable adjustment of the filler loading and carbonization temperature would effectively improve the permittivity and achieve a good impedance matching. The multiple loss mechanisms make Ni@NC/NCNTs have excellent EMW absorption performance. The optimal RL of Ni@NC/NCNTs-800 composite could reach −56.05 dB at 3.32 mm thickness with 25 wt% filler loading. Therefore, it provides some ideas for developing high-performance carbon-based composites with three-dimensional conductive network structure. • The conductive network anemone-like Ni@NC/NCNTs composites were obtained at high temperature. • The pyrolysis temperature affects the electromagnetic wave (EMW) absorption properties. • One-dimensional CNTs as conductive bridges enhanced the EMW absorption performance. • Multiple loss mechanisms cooperate to improve the attenuation ability of EMW. [ABSTRACT FROM AUTHOR]

Three ageing treatments, known as T6, T74, and P-T74 (a pre-ageing treatment followed by a T74 treatment) were carried out to investigate their effects on aluminium alloy 7N01. The aspects investigated included the alloy's mechanical properties, microstructure, electrochemical behaviours, and resistance to stress corrosion cracking (SCC). The experimental results showed that in comparison with T74, P-T74 can effectively increase the density of GPI zones in the early stage giving rise to more nucleation sites for the subsequent η′ phase. T74 guarantees more GPII zones than does T6, but only a fraction can transform into the η' phase, which leads to the lowest hardness and mechanical strength of all treated alloys studied here. Compared with the T6 and T74 ageing treatments, P-T74 showed the highest self-corrosion potential, lowest self-corrosion current density, and largest spacing between the η phase along the grain boundaries, which was an indicator of its increased resistance to SCC. • The P-T74 treatment can effectively increase the density of GPI zones and GPII zones in the early stage and giving more nucleation site for the subsequent η′ phase. • Compared with alloy in T6 and T74 aging, the alloy in P-T74 shows an increase in the resistance to SCC. [ABSTRACT FROM AUTHOR]

Flexible supercapacitors (SCs) are pivotal in the development of wearable and portable electronic devices because of their exceptional power density, high charge/discharge rates, extended cycle life, lightweight, and flexibility. Graphene (G)-based macroscopic materials, such as one-dimensional fibers, two-dimensional films, and three-dimensional aerogels, exhibit a large specific surface area, low mass, excellent flexibility, and high conductivity. These properties make them highly suitable for use as flexible electrode materials in SCs. However, the low energy density of G-based materials hinders their application in certain fields. Iron oxide (Fe 2 O 3) has garnered considerable attention as a negative electrode material because of its low cost, high theoretical capacity, and environmentally friendly nature. However, its practical application is limited because of its poor cycling stability, easy agglomeration, and low electrical conductivity. The combination of G with Fe 2 O 3 to form a composite material not only addresses the issues of volume change and agglomeration associated with Fe 2 O 3 , but also establishes a robust conductive network that improves the electrochemical performance of composite electrodes. Therefore, the construction of SCs using Fe 2 O 3 /G composite electrodes has gained considerable research attention in recent years. We present a comprehensive review of the recent progress in the design of Fe 2 O 3 /G composites as electrode materials for flexible SCs. In addition, we discuss the current challenges and future prospects associated with the use of Fe 2 O 3 /G composites in flexible SCs. [Display omitted] • Recent progress in the design of iron oxide/graphene composites as electrode materials for flexible SCs is reviewed. • The fabrication methods are discussed in depth to provide insight into various development strategies. • The design strategies of iron oxide/graphene composites with different dimensions were comprehensively discussed. • Challenges in iron oxide/graphene composites-based flexible supercapacitors development were described. [ABSTRACT FROM AUTHOR]

The rapid surge in sales of electronic devices and electric vehicles has created an ever-increasing demand for batteries that excel in terms of both safety and energy density. Solid-state batteries (SSBs), as compared to conventional liquid electrolyte-based lithium-ion batteries, have emerged as pioneers at the forefront of the transformation of lithium-ion battery technology, distinguished by their exceptional safety features and elevated energy density. Among the numerous candidate materials in the realm of solid-state electrolytes (SSEs), the garnet-type Li 7 La 3 Zr 2 O 12 (LLZO) stands out due to its exceptional ionic conductivity, shear modulus, and chemical stability. However, inadequate contact between LLZO and the cathode, anode, and even within LLZO itself have been a substantial impediment to the practical application of solid-state batteries. In this review, we delve deeply into the diverse types of interfaces and the associated challenges they present, providing a meticulous analysis of improvement strategies tailored to each specific issue. Finally, we offer an extensive discussion on the challenges and prospective future developments of LLZO in the realm of SSBs, with the aim of contributing to the sustainable advancement of energy storage technologies. [ABSTRACT FROM AUTHOR]

Two-dimensional Ti 3 C 2 MXene with high bulk density can act as prospective electrode material to construct high volumetric energy density supercapacitors. Herein, a series of nitrogen-doped Ti 3 C 2 (N-Ti 3 C 2) films are successfully synthesized by adjusting the quantity of urea using a facile solvothermal method. The incorporation of nitrogen atoms can enlarge interlayer spacing and diminish -F terminal groups of Ti 3 C 2 to promote the diffusion and intercalation of electrolyte ions, and bring about defect sites to provide more electrochemical reactive sites, thus improving the specific capacitance of N-Ti 3 C 2. As a result, the 2.0 N-Ti 3 C 2 film shows the highest volumetric capacitance of 2898.5 F cm−3 at scan rate of 2 mV s−1 in 3 M H 2 SO 4 solution, which is mainly attributed to its high pyridinic N content and low -F terminal groups. Density functional theory (DFT) calculations indicate that the doped N atoms have a higher adsorption energy for protons to enhance the pseudocapacitance of 2.0 N-Ti 3 C 2 electrode, and the increased density of states demonstrate the improvement of its electric conductivity after N doping, which promotes the rate performance of 2.0 N-Ti 3 C 2 electrode. The assembled symmetric supercapacitor based on 2.0 N-Ti 3 C 2 film delivers a high volumetric energy density of 40.8 Wh L−1 and good cycling stability. Our work provides an effective and alternative strategy to improve capacitance of other MXenes for high-performance supercapacitors. [Display omitted] • Flexible nitrogen-doped Ti 3 C 2 films are synthesized by a solvothermal method. • Nitrogen atoms can enlarge interlayer spacing and generate defect sites in Ti 3 C 2. • High pyridinic N can act as electron-donors to absorb more electrolyte ions of H+. • Low -F terminal groups are beneficial to enhance pseudocapacitance of N-Ti 3 C 2. • Optimal 2.0 N-Ti 3 C 2 shows a volumetric capacitance of 2898.5 F cm−3 at 2 mV s−1. [ABSTRACT FROM AUTHOR]

The magnetism and magnetocaloric effect (MCE) of some rare-earth (RE)-based oxides have attracted special attention due to their interesting physical and chemical properties, such as easy fabrication and high chemical stability. In this paper, the CaErAlO 4 polycrystal compound synthesized by the high-temperature solid-state method manifests the considerable second-order reversible MCE near the temperature of liquid helium. This compound crystallizes in the perovskite-like K 2 NiF 4 -type structure with the space group of I 4/mmm. The negative paramagnetic Curie temperature suggests that antiferromagnetism is dominant in the material and the moderate magnetization is mainly contributed by the ferromagnetic interaction in the sample. The measured isothermal magnetic entropy changes (∆ S M) at 3 K are 14.3 and 22.9 J/kg K under 0–20 and 0–50 kOe field changes, respectively. They are greater than those of most RE-based oxides. Our results indicate that the CaErAlO 4 compound is a promising candidate for cryogenic magnetic refrigeration. • Polycrystal CaErAlO4 was synthesized by the high temperature solid state method. • The antiferromagnetic interaction is dominant in the ground state of the material. • Magnetic entropy changes of CaErAlO4 surpass those of many materials near 3 K. [ABSTRACT FROM AUTHOR]

Microporosity and second phases are typical components for casting 2050 alloy. In this paper, the evolution of both microporosity and the second phases during hot deformation of casting 2050 Al-Li alloy was studied. Firstly, based on industrial CT technology, the typical morphology characteristics of micropores during the hot deformation process of the alloy were studied and related statistics were carried out. The results show that with the increase of deformation strain, the volume, volume ratio, and porosity of the micropores gradually decreased, and the roundness gradually increased. Secondly, the detailed evolution mechanism of the second phases during hot deformation was studied by SEM, XRD, and TEM. It was found that with the increase of deformation strain, the thin plate T 1 phase gradually undergoes shearing and exhibits bend-shaped morphology in the SEM image, which was essentially a process of stress transfer from Al matrix to the T 1 phase. Meanwhile, the T 1 phase also experienced thinning and secondary precipitation. This is mainly attributed to the intensive interaction between the alloying elements within T 1 phase and the dislocations pile-up around T 1 phase during the hot deformation process. While for the large-size intermetallic phase AlCuFeMn, it breaks up gradually and oxide inclusion is generated at the broken site, which provides favorable conditions for the initiation and propagation of cracks during hot deformation. From TEM observation, it is found that there is Al 6 Mn intermetallic phase in the alloy matrix with different morphologies under different deformation strains. When the deformation strain reaches 70%, a large number of nanometer Al 6 Mn particles are dynamically precipitated near the dislocations. • Based on industrial CT technology, the typical morphological characteristics of microporosity during the hot deformation of 2050 Al-Li alloy were studied. • The second phase present in the as-cast and hot-deformed forms of 2050 Al-Li alloy were investigated to reveal the evolution of second phase during the hot-deformation process. • The second phase present in the as-cast and hot-deformed forms of 2050 Al-Li alloy were investigated to reveal the evolution of second phase during the hot-deformation process. • The Al6Mn intermetallic phase shows different morphologies during hot deformation. And a large number of nanoscale Al6Mn particles are dynamically precipitated near the dislocations. [ABSTRACT FROM AUTHOR]

The effects of burnishing-assisted two-stage aging (BATSA), including pre-aging, burnishing, and subsequent aging (SA) on the microstructural evolution, precipitation, and hardening behavior of Al-Zn-Mg-Cu alloy were systematically investigated. Transmission electron microscopy, X-ray diffraction, small-angle X-ray scattering, and Vickers microhardness tests were used to analyze the above-mentioned characteristics of the burnished-layer alloys and the matrix-layer alloys, respectively. The BATSA treatment promotes a concentrated distribution of precipitate sizes, delaying phase coalescence and maintaining a relatively dispersed precipitate distribution. Moreover, the persistent nucleation of Guinier-Preston (GP) zones in burnished alloys was observed during SA. These results are conducive to the enhancement of the dislocation storage capacity of nano/ultra fine-grained alloys (the decrease in dislocation density of pre-aged burnished alloy was about 65% that of non-pre-aged burnished alloy). Based on this, dynamic nucleation induced by pre-aging and burnishing resulted in a better synergy of multiple strengthening mechanisms, significantly shortening the time to peak hardness in pre-aged burnished alloys to about 1/3 that in non-pre-aged matrix alloys, and maintaining hardness stability. Moreover, it was found that the critical width of the in situ phase transformation from GPII zone to η' precipitate can be as low as 3–4 at. planes. [Display omitted] • Burnishing-assisted two-stage aging accelerates hardening and stabilizes hardness. • Delayed intragranular phase coalescence enhances dislocation storage capacity. • Burnishing optimizes multiple hardening mechanisms through dynamic nucleation. • In-situ η' phase nucleation can occur in GPII zone with 3–4 at. layers. [ABSTRACT FROM AUTHOR]

The thermal shock stability and oxidation resistance of Al 2 O 3 –C refractories are of critical importance for iron and steel making processes. In rapid and repeated thermal shock environments, materials require excellent thermal shock stability and oxidation resistance. In this study, nano-BN synthesized was used to introduce Al 2 O 3 –C refractories, as well as in evaluating the oxidation resistance and thermal shock resistance of the materials. The results shows that B 2 O 3 was formed rapidly in the refractory containing nano-BN under low temperature oxidation, hence, it led to the decrease of the formation temperature of the dense insulating layer. As a result, the low temperature oxidation resistance of the material was improved. Simultaneously, at high temperatures, Al 18 B 4 O 33 enhanced the formation kinetics of Al 6 Si 2 O 13 by providing epitaxial nucleation sites, forming a synergistic structure of Al 18 B 4 O 33 and Al 6 Si 2 O 13. This change promoted the connection of the oxide layer, thereby greatly improving the oxidation resistance of the material. Moreover, the introduction of nano-BN was beneficial for improving the thermal shock stability of Al 2 O 3 –C refractories. • Oxidation resistance and thermal shock resistance of low-carbon Al 2 O 3 –C refractories were improved by synthesize nano-BN. • An oxidation model of the synergistic effect of mullite-type Al 18 B 4 O 33 and Al 6 Si 2 O 13 were proposed. • Oxidation resistance mechanism of low-carbon Al 2 O 3 –C refractories were clarified. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) of alloys has attracted much attention in recent years for making geometrically complex engineering parts owing to its unique benefits, such as high flexibility and low waste. The in-service performance of AM parts is dependent on the microstructures and grain boundary networks formed during AM, which are often significantly different from their wrought counterparts. Characteristics such as grain size and morphology, texture, and the detailed grain boundary network are known to control various mechanical and corrosion properties. Advanced understanding on how AM parameters affect the formation of these microstructural characteristics is hence critical for optimising processing parameters to unlock superior properties. In this study, the difficult-to-weld nickel-based superalloy Inconel 738 was fabricated via electron-beam powder bed fusion (EPBF) following linear and random scanning strategies. Random scanning resulted in finer, less elongated, and crystallographically more random grains compared to the linear strategy. However, both scanning strategies achieve unique high grain structure stability up to 1250 ℃ due to the presence of carbides pinning the grain boundaries. Despite significant difference in texture and morphology, majority of grains terminated on {100} habit planes in both linear and random built samples. The results show potential for controlling grain boundary networks during EPBF by tuning scan strategies. • Electron powder bed fusion Inconel 738 builds possess thermally stable grain structures up to 1250 ℃. • Change of scanning strategy from linear to random results in texture randomization and grain refinement. • The unique thermal stability can be due to the pinning of grain boundaries by carbides. • Grain boundaries mostly terminate on {100} habit planes irrespective of the scanning strategy. [ABSTRACT FROM AUTHOR]

Electromagnetic pollution resulting from the electronic communication can be mitigated by using microwave absorbers. The magnetic N-doped carbon foams with diverse surface morphologies as absorbers were synthesized via alkalization treatment, hydrothermal reaction, and carbothermic reduction reaction. The microstructure, electromagnetic parameters, and microwave absorption properties can be tailored by adjusting thermal treatment temperatures. The results indicated that the composites exhibit exceptional microwave absorption properties, with a minimum reflection loss of −44.15 dB at 11.18 GHz and an effective absorption bandwidth of 5.3 GHz at a thickness of 1.53 mm. The exceptional microwave absorption properties can be attributed to the synergistic effect of superior impedance matching, robust dielectric loss, and magnetic loss. The far-field radar cross section (RCS) is also reduced, achieving a maximum RCS reduction value of 14.6 dBm2. The present study presents a novel concept for the fabrication of lightweight and broadband microwave absorbing materials. • The magnetic foams with diverse surface morphologies were synthesized. • The composite exhibits high-performance microwave absorption. • Electromagnetic properties and absorption mechanisms were investigated in detail. • An effective absorption bandwidth of 5.3 GHz can be achieved. [ABSTRACT FROM AUTHOR]

In this work the effects of Al and Ti element addition on the microstructure and mechanical properties of CoCrNi medium-entropy alloys (MEAs) has been investigated. A novel (AlTi) 2x (CoCrNi) 100–2x MEAs was fabricated by using powder plasma arc additive manufacturing technique. The influences of Al and Ti elements on the microstructure, mechanical properties and strengthening mechanisms were analyzed by XRD, EBSD and TEM. The (AlTi) 2x (CoCrNi) 100–2x MEAs exhibited columnar crystal structure, but the average grain size and texture decreased continuously with increasing values of x. Moreover, tensile test results showed that (CoCrNi) 90 Al 5 Ti 5 alloy possessed strength-ductility balance (yield strength, ultimate tensile strength and elongation to failure of 664 MPa, 897 MPa and 19.3 %, respectively). The analysis on the strengthening mechanism showed that the solid solution strengthening effect was more dominant with increasing of the x in all alloys. (CoCrNi) 94 Al 3 Ti 3 and (CoCrNi) 90 Al 5 Ti 5 have similar average grain sizes, wherein the difference in mechanical properties between both the alloys can be mainly attributed to the formation of fine grain sizes. (CoCrNi) 90 Al 5 Ti 5 has a small amount of dislocations, solid solution strengthening and grain boundary strengthening are the main sources of the excellent properties. • A novel (AlTi) 2x (CrCoNi) 100–2x MEAs were firstly produced by powder plasma arc additive manufacturing. • The (CoCrNi) 90 Al 5 Ti 5 MEA reaches a balance between strength and ductility well comparing with the current HEAs/MEAs. • The main strengthening contributions are solid solution strengthening and grain boundary strengthening. [ABSTRACT FROM AUTHOR]

Intermediate-temperature solid oxide electrolysis cells (IT-SOECs) have recently attracted great interest in steam electrolysis. However, the performance of IT-SOECs is substantially influenced by the polarization loss encountered at the traditional hydrogen electrode interface. Herein, we reported an innovative approach to address this challenge by modifying the interface of hydrogen electrode and electrolyte. NiO-BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (NiO-BZCY) nanocomposite with an even distribution of NiO and BZCY was synthesized by a one-step combustion method and utilized to fabricate a hydrogen electrode functional layer (HFL). In comparison with the conventional hydrogen electrode fabricated by the ball-milling method, the developed double-layer hydrogen electrode structure exhibits a gradient porosity with macropores at the electrode substrate and micropores at HFL. The optimized electrode microstructure provides both adequate gas diffusion pathway and enlarged three-phase-boundary for effective electrochemical reaction. Consequently, the polarization loss is significantly reduced, leading to a discernible enhancement in the electrolysis performance of the IT-SOECs. [Display omitted] • The cathode microstructure is modified with hydrogen electrode functional layer made by one-step combustion of NiO-BZCY. • The graded-porous structure improves gas diffusion and triple-phase boundary length in hydrogen electrode. • High current density of 0.74 A cm−2 is achieved at 1.3 V and 700 °C. • The polarization loss is effectively reduced at the cathode/electrolyte interface. [ABSTRACT FROM AUTHOR]

Lead halide perovskite solar cells can be significantly improved with multifunctional additives such as carbon dots (CDs) with amine terminals via defect passivation and band alignment. Here, we determine rational guidelines for the usage of such quantum dots in perovskite solar cells by systematically studying their effects on crystal quality and carrier transport. The amine-terminated CDs homogeneously dispersed in precursors improve the crystal quality of perovskite films, but they reduce the hole mobility hampering hole extraction. In contrast, CDs deposited between the electron transport layer and active layer could promote spin-coated film quality and electron's extraction efficiently. So, the approaches of the carbon dots in device alters semiconductor properties and energy level structure. Interface engineering achieve better crystal quality and energy level alignment, which in turn affects charge collection, thereby increasing current density and power conversion efficiency. According to the findings of this study, when considering defect passivation by additives, the energy band alignment of the device should also be considered, since this could change carrier dynamics and device performance differently. [Display omitted] • Based on the effects of amine-terminated carbon dots, a rational guideline for the use of such CDs in perovskite solar cells was determined. • Carbon dots are able to passivate grain boundaries, optimize device interfaces, improve film morphology, align energy levels, and enhance carrier mobility. • The CDs homogeneously dispersed in precursors improve the crystal quality of perovskite films, but they increased energy barrier and hampered hole extraction. • The interface engineering via depositing the CDs between the electron transport layer and the active layer improves film quality and promotes electron extraction. • The interface engineering suggested comprehensive improvements over the precursor engineering, thereby leading to current density and power conversion efficiency changes. [ABSTRACT FROM AUTHOR]

The glass with components of 50SiO 2 -20B 2 O 3 -20Na 2 O-6ZnO-3MoO 3 -1Y 2 O 3 (mol%) was synthesized by the melt-quenching method, and the corresponding glass-ceramics were obtained after heat treatment. The crystallization behavior of the glass was characterized by the DSC test. By carefully examining the structure and grain size of the NaY(MoO4) 2 crystals with scheelite structure using XRD and SEM, it can be confirmed that the crystal size steadily increases after increasing the crystallization temperature or extending the crystallization time, which is in the range of 27–45 nm. The transmittance of glass-ceramics somewhat declines compared to the precursor glass, although it remains high (>80 %). Under the excitation of 365 nm, the glass-ceramic shows a broad emission band, which is related to the charge transfer of Mo6+→O2- in the [MoO 4 ]2- unit. The glass-ceramic is heat-treated at 590 °C for 3 h as the optimal heat treatment schedule, and its CIE chromaticity coordinate is located in the blue-light region, indicating the potential application of the non-rare-earth-doped self-activated light-emitting glass-ceramics containing single-phase NaY(MoO4) 2 in the blue light-emitting field. • Transparent glass-ceramics with single-phase NaY(MoO4) 2 were obtained. • Optimum heat treatment schedule was determined to be 590 °C for 3 h. • A kind of self-activated blue luminescent material without rare earth was prepared. • Glass-ceramic containing NaY(MoO4) 2 can be applied to blue light display devices. [ABSTRACT FROM AUTHOR]

The development of wide-band microwave absorbing materials based on carbonaceous fillers remains a great challenge. In this study, carbon nanotubes (CNT) assembled coronal hollow clusters with efficient microwave absorbing performance have been obtained through successive hydrothermal and calcination process. Microstructural analysis reveals the distinct features of multiple assembly structures in the fabricated materials. The electromagnetic responses of Ni/CNT assembled clusters were examined across a frequency range of 2–18 GHz. Results demonstrate that the microwave frequency dispersion of electromagnetic parameters and reflection loss of Ni/CNT clusters are strongly influenced by weight loading. Multi-absorbing peaks with reflection loss better than − 40 dB could be achieved, while the equivalent absorbing band for RL < −10 dB covers 3.2–18 GHz, which account for 92.5% of the whole evaluated frequency range, and 62.5% for condition of RL < −20 dB. Furthermore, intrinsic attenuation beyond thickness derived semi-wavelength resonant absorption makes a major contribution to this superior performance. The underlying mechanism of dielectric response was investigated through Cole-Cole analysis and finite element simulation. 'Micro-dipoles' relaxation and hopping relaxation originated from defects within CNT and barrier between CNT, while the high magnetic dissipation capability of Ni nanoparticles make a major contribution to overall absorbing performance. All these are beneficial to regulation and optimization of microwave absorption performance of novel Ni/ CNT functionalized multistage architecture. [Display omitted] • Ni/CNT clusters were prepared through a sample solvothermal method; • Carbon nanotubes were assembled in situ into coronal hollow spherical multilayer carbon nanotube clusters; • The absorption efficiency of CNT is improved by anisotropic strong dielectric loss and multi-layer structure. • The microwave absorption of the new Ni/ CNT functionalized multistage structure greatly improves the performance. [ABSTRACT FROM AUTHOR]

(Zr 0.25 Hf 0.25 Ti 0.25 Ta 0.25)C high-entropy ceramics (ZHTTC) with exceptional compressive strength were prepared by spark plasma sintering at different temperatures (1900–2200 ℃). The effect of average grain size on compressive strength were investigated. The results indicate that the compressive strength degrades with the increase of the average grain size. The grain growth from 3.309 ± 0.603–9.25 ± 1.98 µm as the temperature elevated from 1900 to 2200 ℃. The ZHTTC-1900 achieves the maximum compressive strength of 3620 ± 180 MPa, while the compressive strength of ZHTTC-2200 is 1912 ± 203 MPa, which is 47 % lower than that of ZHTTC-1900. The increase of sintering temperature not only causes the increased average grain size, but also induces the decrease of grain boundary precipitation sites and adhesion of grain boundaries. The above reasons result in the degradation of compression properties. • ZHTTC-1900 with exceptional compressive strength of 3620 ± 180 MPa was achieved. • The segregation of Zr, Hf at the GB and grain refinement result in the exceptional compressive strength of ZHTTC-1900. • Effect of SPS conditions on grainsize was addressed, increased grainsize causes a 47 % decrease of compressive strength. [ABSTRACT FROM AUTHOR]

The green and facile synthesis of high performance anodes is of significant importance for development of lithium ion batteries (LIBs). Herein, a novel coordination chemistry-assisted method is demonstrated to successfully prepare a superior performance Fe 2 O 3 /C composite anode for LIBs. This method does not involve time-consuming pre-preparation of carbon materials and use of expensive sophisticated instruments and multiple harmful reagents, exhibiting relatively green and facile features over most of other methods. This Fe 2 O 3 /C composite consists of Fe 2 O 3 nanoparticles embedded in a porous carbon sheets assembled hierarchical matrix. Moreover, it finds that this beneficial architecture endows as-prepared Fe 2 O 3 /C with improved conductivity, enhanced kinetics, high capacitive contribution and good structure stability. In consequence, this Fe 2 O 3 /C anode exhibits superior electrochemical properties such as high capacity, long life and good rate performance, with 756.1 and 545.4 mA h g−1 after 200 cycles at 200 and 1000 mA g−1, respectively. The relatively ecofriendly and simple preparation process as well as superior electrochemical performance make this Fe 2 O 3 /C anode promising for LIB application. This work also offers a guiding significance for designing and developing ecofriendly and facile preparation methods of other metal oxides/carbon composites for advanced LIB anodes. [Display omitted] • A novel coordination chemistry-assisted method was used to prepare Fe 2 O 3 /C composite. • This method exhibited relatively green and facile features over other methods. • The effect of structure on lithium storage performance of Fe 2 O 3 /C was clarified. • The as-prepared Fe 2 O 3 /C showed superior performance as LIB anodes. • This work offered a guiding significance for preparing other metal oxide/carbon composite anodes. [ABSTRACT FROM AUTHOR]

YbFeO 3 exhibits spin switching (SSW) and spin reorientation transition (SRT) at low temperatures, but its mediocre magnetocaloric properties limit its further applications. As for TbFeO 3 showing a large magnetocaloric effect, its SSW is missing. Motivated by this, we chemically put Yb and Tb with a ratio of 1:3 on the rare-earth site. Potential applications of magnetic and magnetocaloric properties are both preserved in one single phase Yb 0.25 Tb 0.75 FeO 3 , which is exceptional among the rare-earth orthoferrites. Spin switching temperature (T SSW) in the field-cooled-cooling mode increases to around 100 K compared with YbFeO 3. A novel multiple SSW emerges in the field-cooled-warming mode originating from the complex competing magnetic interactions between Yb/Tb and Fe sublattices. We also addressed the mechanism of spin modification of magnetic ions with temperatures. Arrott plots created from the isothermal magnetization curves demonstrate that SRT is a second-order phase transition. The negative entropy change (refrigeration capacity) vs. temperatures [ − ∆ S m (RC) vs. T ] diagrams indicate that the − ∆ S m (RC) are effectively increased compared with YbFeO 3 by rare-earth doping. The pronounced magnetic refrigeration performance and SSW effect with a low-field dependence make it promising to be employed in both magnetic sensing and refrigeration devices. [Display omitted] ● The spin-switching effect appears in both cooling and warming mode. ● The multiple spin-switching effect are observed. ● The intronic mechanism of magnetic sublattices spin flipping is depicted. ● The giant magnetocaloric effect is observed. ● Magnetic refrigeration is highly improved compared with YbFeO 3. [ABSTRACT FROM AUTHOR]

The lead-free BiFeO 3 -BaTiO 3 (BF-BT) based ceramics with large piezoelectric coefficient (d 33) have been desired for promising applications in high-temperature fields. Herein, the 0.7Bi(Fe 0.9985 Mn 0.0015)O 3 -0.3BaTiO 3 ceramics with different grain sizes are intentionally prepared by solid-state method, and a large d 33 (232 pC/N) and high Curie temperature T c (501 °C) are simultaneously achieved in the case of large grain size (>9 µm). X-ray diffraction and Rietveld refinement analyses indicate that these coarse-grained samples possess stronger rhombohedral distortion and enlarged lattice parameter compared to fine-grained samples, which make domain switching easier and give rise to the increase in strain. As a result, the piezoelectric and ferroelectric properties of such samples are significantly improved with increasing grain size from 3.05 µm to 9.07 µm. In addition, electric domain configuration and field-induced strain further prove that the strong piezoelectric response in coarse-grained samples is attributed mainly to enhanced non-180° domain mobility. This study reveals the origin of large piezoelectric response in coarse-grained BF-BT ceramics, and proposes an effective approach to improve the piezoelectric properties of BF-BT ceramics. • High d 33 and T c are simultaneously achieved in BF-BT ceramic by adjusting grain size. • The origin of piezoelectric response in coarse-grained BF-BT ceramic is uncovered. • The effects of grain size on the electric properties of BF-BT ceramic are explored. [ABSTRACT FROM AUTHOR]

Supercapacitors based on flexible fabrics are considered promising wearable energy storage devices due to their skin adaptability and high mechanical properties. However, enhancing the electrical conductivity of flexible fabric substrates and optimizing the loading of active materials remains a challenge. Here, we propose a concept of functionalized ink interlayer to improve the performance of fabric-based supercapacitors. The functionalized ink interlayer not only has good electrical conductivity but also guides the loading of polyaniline (PANI) and facilitates charge transfer at the electrode/electrolyte interface, generating a synergistic effect with the active material. The areal capacitance (323.3 mF cm−2) of cotton fabric/conductive carbon oil/ink@PANI supercapacitor is greater than the sum (210.2 mF cm−2) of cotton fabric/conductive carbon oil/ink supercapacitor and cotton fabric/conductive carbon oil@PANI supercapacitor. Additionally, the maximum energy density of supercapacitor with ink interlayer is 28.5 μWh cm−2 and the maximum power density is 2057 μW cm−2. The electrode with ink interlayer can maintain a fast electrodynamic process and the cycling stability is also improved. Finally, interdigital and tree-like clothing appliques were prepared and sewn onto clothing to realize wearable energy storage function using ink@PANI-based electrodes. This work provides important references for the development of fabric-based supercapacitors. • A functionalized ink interlayer is proposed to prepare fabric-based supercapacitors. • The ink interlayer can regulate the loading of PANI and enhance the performance. • Conductivity and capacitance of fabric electrode are improved with ink interlayer. • Wearable energy devices are demonstrated based on ink-assisted fabric electrodes. [ABSTRACT FROM AUTHOR]

Ni2+ doped and Ni2+/Er3+ co-doped Gd 2 MgTiO 6 (GMT) phosphors have been synthesized by conventional high-temperature solid-state reaction method. First-principles calculation and X-ray diffraction analysis proves that Ni2+ ions occupy the Mg2+ sites in the Gd 2 MgTiO 6 matrix at low Ni2+ doping concentration and begin to occupy Ti4+ sites at high Ni2+ doping concentration. The near infrared emissions of Ni2+ ions occupying Mg2+ and Ti4+ sites peak at 1344 nm and 1412 nm, respectively, forming a broad near infrared emission band from 1100 nm to 1700 nm. It is found that Ni2+/Er3+ co-doped Gd 2 MgTiO 6 phosphor is capable to up-convert near infrared photons in the wavelength range of 870–1700 nm to visible 532 nm, 555 nm and 666 nm emission, caused by the energy transfer sensitization process from Ni2+ to Er3+. The Ni2+ and Er3+ concentration dependent up-conversion properties have been investigated and it is found that the Gd 2 MgTiO 6 : 2%Ni2+/5%Er3+ phosphor shows the strongest up-conversion emission, in which the energy transfer efficiencies from the Ni2+ ions occupying Mg2+ and Ti4+ sites to the Er3+ ions are 81.5% and 79.3%, respectively. The Gd 2 MgTiO 6 : 2%Ni2+/5%Er3+ phosphor shows yellow emission under the irradiation of 1342 nm and 1550 nm lasers, and green and orange-red emissions under the irradiation of 980 nm and 1064 nm laser, respectively. The broad band excitability and multi-color up-conversion performance of the Ni2+/Er3+ co-doped Gd 2 MgTiO 6 phosphor suggest that it has wide application prospect in anti-counterfeiting, solar cell efficiency enhancement, infrared detection and so on. • Broadband near infrared emission of Ni2+ is firstly witnessed in Gd 2 MgTiO 6. • Gd 2 MgTiO 6 : Ni2+/Er3+ can up-convert 900–1700 nm light into visible emission. • Ni2+→Er3+ energy transfer and Er3+ excited absorption performs the up-conversion. • The phosphor shows different up-conversion color excited at different wavelength. [ABSTRACT FROM AUTHOR]

Rutile TiO 2 is a competitive white pigment due to its high refractive index and inertness. Uncolored Mg2+ is a promising dopant for the production of TiO 2 pigment because it promotes the anatase-to-rutile phase transition of TiO 2 at lower temperatures (vs. Al3+). However, research on the impact of Mg2+ concentration on TiO 2 phase transition is scarce, and the defect structures are still unknown. In this study, the effect of Mg2+ doping concentration on TiO 2 phase transition was investigated, and the defect structures of Mg2+ doped TiO 2 were proposed. Over 96% conversion of anatase to rutile was achieved with 1.48% Mg doping at 875 °C (vs. Al3+, 1050 °C) for 1 h. By using the Rietveld method, two defect structures—interstitial Mg2+ (Mg int) and substitute Mg2+ (Mg sub)—were quantified. A correlation between the defect structures and the effect on phase transition was established. At low Mg doping level (<1%), the Mg int dominates and weakly promotes the phase transition; At high Mg doping level (>1%), the Mg sub dominates and strongly promotes the phase transition. Additionally, a possible mechanism for the formation of defect structures and how that affects phase transition was proposed. The present results may provide insights into TiO 2 pigment production and modulation of TiO 2 defects for phase transition control and other applications. • 96% conversion of anatase to rutile was achieved at 875 °C (1050 °C in industry). • The two defect structures of Mg2+ doped TiO 2 —interstitial Mg2+ and substitute Mg2+—were quantified by Rietveld method. • The correlation between defect structures and phase transition is established. • The possible mechanism for the formation of defect structures and how that affects phase transition was proposed. [ABSTRACT FROM AUTHOR]

In this study, a novel rare-earth element-free Mg–Bi–Sn–Mn alloy system (with Bi and Sn as double principal elements) was developed to overcome the applicability limitations of Mg alloys while avoiding the use of rare-earth elements. The characteristics of the precipitates and creep performance of a peak-aged Mg–5Bi–5Sn–0.5Mn (BTM550) alloy were investigated. The results indicated an unexpected deterioration in the creep properties of the rare-earth element-free alloy after peak-aging treatment. This is primarily due to the change in the orientation relationships (ORs) of numerous static and dynamic precipitates (containing Mg 2 Sn and Mg 3 Bi 2) to a basal plane orientation that has a limited ability to block dislocations. The ORs of Mg 2 Sn and Mg 3 Bi 2 precipitates with the matrix are (022) Mg2Sn //(0002) Mg , [01-1] Mg2Sn //[1−210] Mg and (10−10) Mg3Bi2 //(0001) Mg , [0001] Mg3Bi2 //[1−210] Mg , respectively. Both, submicron Mg 2 Sn and Mg 3 Bi 2 precipitates, exert equivalent effects on the deterioration of the creep properties. Additionally, based on the calculated stress exponent values and transmission electron microscopy results, we determined that the creep process is controlled by cross-slip in the peak-aged BTM550 alloy. [ABSTRACT FROM AUTHOR]

As typical energy storage devices, the extensive application of the supercapacitors is largely restricted by their relatively low energy storage efficiency, which motivates the development of various advanced electrode materials with sophisticated architectural design. Herein, we put forward a robust and controllable approach to construct a series of hybrid nanoarchitectures consisting of nanoflower-shaped MnO 2 nanocrystals grown on super-thin Ti 3 C 2 T x MXene nanosheets (MNF/Ti 3 C 2 T x) via a convenient co-precipitation process. Such a delicate configuration enables the nanoarchitectures to provide prominent structural merits, such as 2D thin-sheet structure with large surface area, porous MnO 2 nanoflower frameworks, activated electronic structure, and high electron conductivity. As a consequence, the optimized MNF/Ti 3 C 2 T x electrode manifests superior electrochemical capacitive properties with a maximum specific capacitance of 348.5 F g−1 at 0.5 A g−1, excellent rate property, and reliable cycling stability with 91.9% retention of initial capacitance after 5000 cycles, all of which are more competitive than those of conventional MnO 2 and Ti 3 C 2 T x electrodes. [Display omitted] • The stereoassembly of ε-MnO 2 nanoflowers on 2D Ti 3 C 2 T x MXene nanosheets is achieved. • MXene nanosheets are able to optimize the electronic and geometric structures of MnO 2. • The nanoflower-shaped MnO 2 affords numerous accessible electrochemically active sites. • The derived nanoarchitectures are expected to serve as promising electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

With the development of electronic products to miniaturization and high frequency, high-performance flexible electromagnetic interference (EMI) shielding materials are urgently needed to deal with electromagnetic pollution. Two-dimensional transition metal carbide/polyimide (Ti 3 C 2 T x MXene/PI) films were synthesized by in situ polymerization and a simple scratch method in this paper. The Ti 3 C 2 T x MXene nanosheets give the films good EMI shielding effectiveness (SE) and electrical conductivity. Specifically, the film with a thickness of 0.11 mm (Ti 3 C 2 T x content of 30 wt%) exhibits an EMI SE of 34.73 dB and a specific EMI SE (SE/thickness) of 315.73 dB/mm in the frequency range of 8.2–12.4 GHz (X-band). In addition, the films have a tensile strength of 67.58 MPa, and a high decomposition temperature of 510 ℃ in N 2 atmosphere. Therefore, we believe that the prepared Ti 3 C 2 T x /PI films with good comprehensive performance have enormous potential in the field of lightweight and flexible EMI shielding materials. • Ti 3 C 2 T x MXene/Polyimide composites film was synthesized by in situ polymerization and scraping method. • With the increase of Ti 3 C 2 T x MXene content, the electrical conductivity and EMI SE of the films increased. • The films exhibit good flexibility and tensile properties. • The film with thickness of 0.11 mm exhibited 34.73 dB EMI SE when Ti 3 C 2 T x MXene was added at 30 wt%. [ABSTRACT FROM AUTHOR]

Lithium-metal batteries (LMBs) have attracted special interest owing to their high energy densities. Nevertheless, the unfavorable reactivity of lithium metal (Li metal) leads to the uncontrolled growth of dendrites and formation of unstable solid electrolyte interlayers, which shorten the cycle life of Li metal and limit its wide application. Herein, a conformal and thin protective layer, composed of Sn, an Sn–Li alloy, lithium fluoride (LiF), and polyethylene oxide (PEO) (denoted as Li-Sn-LiF@PEO), is constructed in situ on Li metal via a facile one-step method. This conformal artificial layer not only reduced the subsequent surface reactions of lithium with the electrolytes, but also effectively accommodated the large volume change of the Li-metal anode and suppressed the growth of Li dendrites. Symmetric cells with Li-Sn-LiPEO-modified Li-metal anodes exhibited small voltage hysteresis and outstanding plating/stripping cyclability over 400 h at high current densities and capacities of 20 mA cm−2 and 20 mAh cm−2. When coupled with NCA/NCM523/LiFePO 4 cathodes, the corresponding LMBs exhibited remarkable cycling life and superior rate properties. These encouraging results demonstrate a novel and promising method for long-life and large-scale stable LMBs. [Display omitted] • A conformal and thin protective layer for the Li metal anode is synthesized. • The Li-Sn-LiF@PEO coating layer suppresses the Li dendrite growth effectively. • The modified Li shows good cyclability over 400 h at 20 mA cm−2 and 20 mAh cm−1. • The constructed LMBs achieve superior rate capability and long cycle life. [ABSTRACT FROM AUTHOR]

Tetragonal BaTiO 3 (BT) powder with appropriate size and dispersity is essential for the dielectric layers in multilayer ceramic capacitor technology. In this work, high tetragonality BT powder with controllable dispersion, and particle size was synthesized using combined dispersants and a two-step hydrothermal method. Owing to the synergistic effect of chemical bond force and electrostatic adsorption force between cetyltrimethylammonium bromide (CTAB) and polyvinyl-pyrrolidone (PVP) composite dispersants at a high temperature, the ultrafine BT powder with a high c/a of 1.0090, small size of 236 ± 15 nm and low polydispersity index of 0.336 was achieved. This idea shows great significance for the synthesis of BT powder with high tetragonal, high dispersion, and small particle sizes. • High tetragonality BT powder with controllable dispersion, and particle size was synthesized using combined dispersants and a two-step hydrothermal method. [ABSTRACT FROM AUTHOR]

In this manuscript, an introduced ionic liquids-ethylene glycol-KOH electrolyte system is proposed. Theoretical calculations and experiments show that ionic liquids with stronger hydrophobicity provide better corrosion inhibition for their spontaneous adsorption behavior and water molecule segregation. In this process, the imidazole ring cations play a major role. The electrolyte system reconstructs the Al/electrolyte interface with poor H 2 O, thus has lower self-corrosion rate for [BMIM]PF 6 and contributes to the uniform dissolution of Al anode. Additionally, discharge performance of the full-cell feature same trend, endowing an outstanding capacity of 1971 mAh g−1 and anode utilization of 66.2% in alkaline [BMIM]PF 6 -ethylene glycol electrolyte. In terms of maintaining the activity of the Al-6061 anode whilst keeping low corrosion rate level, the proposed electrolyte system seems to be potential alternative. [Display omitted] • An aluminum-ionic liquid-alkaline electrolyte interface is constructed for Al-air batteries. • Al-molecular H 2 O-poor interface significantly suppresses the self-corrosion via the initiative adsorption of ionic liquid. • Imidazole ring of studied ionic liquids plays a dominant role in the adsorption behavior. [ABSTRACT FROM AUTHOR]

Excess impurity Fe will form various intermetallic compounds in Al-based alloys, such as α-Al 8 Fe 2 Si and β-Al 5 FeSi, which greatly reduce the elongation of alloys. Therefore, Fe removal is a promising approach for high performance Al-based alloy. In this paper, we propose an effective method for the Fe removal from Al-7Si alloys by adding Sn. Based on the thermodynamic calculations, the element Sn was selected for Fe removal. The microstructure of Fe-rich compounds and Fe content in alloy were compared by optical microscope (OM), scanning electron microscopy (SEM) and inductively coupled plasma generation spectrometer (ICP). It was observed that the reduction of Fe content in Sn can reach 33.8%, comparable to the level of adding B. More Fe-rich compounds deposited at the bottom after addition of Sn. However, the phase type and morphology of Fe-rich compound were unchanged. The β-Sn attached to the β-Al 9 Fe 2 Si 2 which was determined by transmission electron microscopy (TEM), and a coherent interface between β-Sn and β-Al 9 Fe 2 Si 2 phase was observed with the orientation of (0 0 1)[1 1 0] β-Sn ∥(2 2 0)[0 0 1] β-Al9Fe2Si2. It deduced that the attached β-Sn with larger density than alloy would lead to more deposition of β-Al 9 Fe 2 Si 2. This study provides an insight into the preparation of high-performance Al-Si alloy by removing Fe from secondary Al alloy with Sn addition. [Display omitted] • Sn is selected for iron removal based on the thermodynamic calculations. • The iron removal rate of Al-7Si-1Fe can reach 33.8% by adding Sn. • The β-Sn will attach to the surface of β-Al 9 Fe 2 Si 2 phase and settle it. [ABSTRACT FROM AUTHOR]

In this work, we synthesized a series of Gd 2 SrAl 2 O 7 : Mn4+/Bi3+/Na+ phosphors by sol-gel method. The experimental results show that there is energy transfer from Bi3+ to Mn4+. By introducing Bi3+ and Na+ ions into the host, emission intensity of the optimal phosphor can be increased to 2.5 times that of Gd 2 SrAl 2 O 7 : Mn4+ and its internal quantum yield is as high as 79.9%. Furthermore, the optimal phosphor also exhibits satisfactory luminescence thermal stability, whose PL intensity at 423 K retained 80.2% of that at room temperature and the activation energy reaches up to 0.45 eV. Mechanism of photoluminescence improvement can be attributed to efficient energy transfer, charge compensation and enhanced crystal rigidity. Packaged LED device exhibits dazzle far red light and its PL spectrum widely overlaps with the absorption band of phytochrome P FR. The performance indexes support the prospective application of the optimal phosphor in plant growth lighting. • The novel layered double-perovskite phosphor Gd 2 SrAl 2 O 7 :Mn4+, Bi3+, Na+ has been prepared by sol-gel method. • Gd 2 SrAl 2 O 7 :Mn4+, Bi3+, Na+ exhibits satisfactory luminescent thermal stability. • Mechanism of luminescent performance improvement is analyzed in detail. • Gd 2 SrAl 2 O 7 :Mn4+, Bi3+, Na+ is suitable for indoor plant growth LED lighting. [ABSTRACT FROM AUTHOR]

The effect of long-term isothermal aging of Haynes 230 super-alloy in an advanced ultra-supercritical (A-USC) power plant at 700 °C for up to 10,000 h on microstructural evolution and tensile behavior. And utilizing a combination of the scanning electron microscope (SEM), X-ray diffraction analysis (XRD), and transmission electron microscope (TEM). Although the grain size and grain boundary M23C6 carbides did not change significantly, the dissolution of intercrystallite primary M 6 C carbides and the precipitation of intracrystalline secondary lamellar M 6 C carbides were observed at 2000 h to 10,000 h. According to the SEM and TEM results, it is shown that the dissolution of primary M 6 C carbides makes the W, Mo, and Cr in the γ matrix increase, while the precipitation process of secondary M 6 C carbides is M+ 6 C→M 6 C. To reduce the interfacial energy of the γ matrix, secondary M 6 C carbides are precipitated in the crystal under long-term aging at 700 °C, with a gradual increase in time content. the best tensile and yield strengths at 750 °C occur after 4000 h of aging, with microscopic voids forming mainly around the granular M 6 C carbides in the crystal, but the solid solution strengthening effect of the matrix provides the strength. The worst strength and elongation occur after 10000 h aging, when the dissolution of granular M 6 C and secondary precipitation of M 6 C carbides are most abundant, interfacial cavity formation of granular M 6 C carbides and brittle fracture of M 6 C carbide particles, and the growth of non-co-grained secondary M 6 C carbides with the matrix allow more microscopic cavities to appear during high-temperature tension, reducing the strength of Haynes 230 and plasticity. • Phase precipitation behavior of Haynes 230 was investigated during long-term aging at 700 ℃. • Precipitation processes of secondary lamellar-like M 6 C carbide were clarified. • Dissolution of primary granular M 6 C carbides was discussed. • Variation in mechanical properties is divided into several stages. • The relationship between precipitation processes and mechanical properties was established. [ABSTRACT FROM AUTHOR]

Herein, to improve the electrical characteristics, ZnO linear resistors mixed with MgO, TiO 2 , Al 2 O 3 , and various concentrations of Sc 2 O 3 (with 0, 0.35, 0.7, and 1.05 wt %) were obtained using the conventional solid-state sintering technique, while the influences of Sc 2 O 3 doping on the micro-morphology and electrical characteristics was investigated in detail. The crystalline phases and microstructure were investigated by X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The dielectric properties and electrical characteristics were evaluated using a precision inductance-capacitance-resistance meter and a high-voltage source meter. Results from SEM micrographs, XRD patterns, and EDS mappings illustrated that the doping of Sc 2 O 3 hinders the growth of ZnO grains. Electric field-current density and resistivity-frequency measurements illustrated that the doping of Sc 2 O 3 improves the linear performance of ZnO linear resistors and increases its grain resistivity and grain boundary resistivity. With Sc 2 O 3 doping, the dielectric properties of the samples are significantly affected, while the resistance-temperature features reveal the negative temperature constant function. By appropriate Sc 2 O 3 doping, the ZnO linear resistors exhibited excellent performance with grain boundary barrier height φ b of 0.0106 eV, nonlinear coefficient α of 1.03, and resistance temperature constant α T of −2.88 × 10−3. It is beneficial to investigate the influence of Sc 2 O 3 doping on the micro-morphology and electrical performances in detail for the preparation of zinc oxide linear resistors with superior performance. • With Sc 2 O 3 doping, the ZnO grain size d is decreasing. • Sc 2 O 3 as a donor additive, enhances the linear characteristics of ZnO linear resistors. • With Sc 2 O 3 doping, the ε r and tanδ of the ZnO linear resistors decrease. [ABSTRACT FROM AUTHOR]

Ti-15Mo alloys have been widely used as biomedical materials. However, problems such as stress shielding and peri-implant infection occur when Ti-15Mo alloys are implanted in vivo. In this study, the function-structure-integrated Ti-15Mo- x Cu (x = 3, 7, 11 and 15 wt%) alloys were prepared by powder metallurgy using Ti, Mo and Cu powders as raw materials. The results revealed that the Ti-15Mo- x Cu alloys were mainly composed of β -Ti, α-Ti and Ti 2 Cu phases. The Ti 2 Cu phase combined with α -Ti formed a layer phase at the grain boundary. The strength of Ti-15Mo- x Cu alloys decreased with Cu content increasing. When the Cu content was 11 wt%, the Ti-Mo-Cu alloy exhibited the higher compressive strength of 318.8 MPa and the lowest elastic modulus of 5.2 GPa. Simultaneously, the concentration of Cu ion release was proportional to the Cu content, which further affected the antibacterial activity. A high concentration of Cu ions was released from the alloys, and then became stable. Antibacterial rates of S. aureus and E. coli beyond 95% with good cytocompatibility can be obtained for the Ti-15Mo-11Cu alloy. This research revealed that the Ti-15Mo-11Cu alloy has excellent mechanical compatibility and antibacterial properties, which could satisfy the requirement for implant of human cortical bones. [Display omitted] • The function-structure-integrate method was used to design Ti-Mo-Cu alloy prepared by powder metallurgy. • The crack propagation mechanism of Ti-Mo-Cu alloy was revealed. • The alloy could possess good mechanical compatibility and cytocompatibility. • The addition of 11-15 wt. %Cu improved antibacterial properties of the Ti-Mo alloy against E.coli and S. aureus. [ABSTRACT FROM AUTHOR]