In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot al...In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable solutions.Nevertheless,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely explored.This study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic materials.The ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree Regression(DTR),and Gaussian Process Regression(GPR)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon steel.Although the GPR method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.展开更多
Anti-perovskite cathodes,typified by Li_(2)FeSO,hold great promise for Li-ion batteries due to their high specific capacity,cost-effectiveness,and ease of production.However,their utilization in high-energydensity bat...Anti-perovskite cathodes,typified by Li_(2)FeSO,hold great promise for Li-ion batteries due to their high specific capacity,cost-effectiveness,and ease of production.However,their utilization in high-energydensity batteries is hindered by low Li intercalation voltage and limited rate performance.This study employs first-principles calculations to assess the impact of element substitutions and doping on the voltage and Li-ion migration energy barrier in Li_(2)TMSO(TM=Cu,Ni,Co,Fe,V,Cr,Ti)anti-perovskite materials.Our findings reveal that replacing the S element with Se or Te in Li_(2)FeSO and Li_(2)MnSO can reduce the voltage.For Li_(2)TMSO(TM=Cu,Ni,Co,Fe,V,Cr,Ti),the voltage increases as TM changes from Ti to Ni.This process closely related to the downward shift of the TM-3d electron orbital energy level.When the energy level difference between TM-3d and S-3p orbital energy levels is large,the voltage is determined by TM-3d orbitals.When the difference is small,S-3p participates in the reaction.Additionally,doping with the inactive element Mg could allow deeper energy level electrons to participate in the reaction,thus increasing the voltage.To simultaneously enhance intercalation voltage and rate performance,we investigated multi-element doping strategies for anti-perovskite cathode materials.Our study establishes a solid foundation the development of high-voltage anti-perovskite cathodes,holding promise for significant advancements in energy storage technology.展开更多
Quantitative analysis of aluminum-silicon(Al-Si)alloy microstructure is crucial for evaluating and controlling alloy performance.Conventional analysis methods rely on manual segmentation,which is inefficient and subje...Quantitative analysis of aluminum-silicon(Al-Si)alloy microstructure is crucial for evaluating and controlling alloy performance.Conventional analysis methods rely on manual segmentation,which is inefficient and subjective,while fully supervised deep learning approaches require extensive and expensive pixel-level annotated data.Furthermore,existing semi-supervised methods still face challenges in handling the adhesion of adjacent primary silicon particles and effectively utilizing consistency in unlabeled data.To address these issues,this paper proposes a novel semi-supervised framework for Al-Si alloy microstructure image segmentation.First,we introduce a Rotational Uncertainty Correction Strategy(RUCS).This strategy employs multi-angle rotational perturbations andMonte Carlo sampling to assess prediction consistency,generating a pixel-wise confidence weight map.By integrating this map into the loss function,the model dynamically focuses on high-confidence regions,thereby improving generalization ability while reducing manual annotation pressure.Second,we design a Boundary EnhancementModule(BEM)to strengthen boundary feature extraction through erosion difference and multi-scale dilated convolutions.This module guides the model to focus on the boundary regions of adjacent particles,effectively resolving particle adhesion and improving segmentation accuracy.Systematic experiments were conducted on the Aluminum-Silicon Alloy Microstructure Dataset(ASAD).Results indicate that the proposed method performs exceptionally well with scarce labeled data.Specifically,using only 5%labeled data,our method improves the Jaccard index and Adjusted Rand Index(ARI)by 2.84 and 1.57 percentage points,respectively,and reduces the Variation of Information(VI)by 8.65 compared to stateof-the-art semi-supervised models,approaching the performance levels of 10%labeled data.These results demonstrate that the proposed method significantly enhances the accuracy and robustness of quantitative microstructure analysis while reducing annotation costs.展开更多
To exploit the combined strengthening effects of nanotwins and carbon nanotubes(CNTs)in Cu matrix composites,the nanotwins with a width ranging from 3 to 30 nm were incorporated into the CNTs-reinforced Cu matrix comp...To exploit the combined strengthening effects of nanotwins and carbon nanotubes(CNTs)in Cu matrix composites,the nanotwins with a width ranging from 3 to 30 nm were incorporated into the CNTs-reinforced Cu matrix composites using cryogenic rolling and optimizing the initial particle size of the raw Cu powders.The formation of nanotwins in the Cu matrix composite reinforced by only 0.2 wt.%CNTs is accompanied by the increased dislocation density and refined Cu grain size,resulting in much better strength−ductility synergy than the referenced composite without significant nanotwins formation.The analysis of strengthening and toughening mechanisms demonstrates that the strength increment mainly derives from grain refinement strengthening,dislocation strengthening,and nanotwin strengthening.The strength increment from the contribution of the nanotwins accounts for 19.9%of the overall strength increment for the composite.Meanwhile,the retention of good tensile ductility can be reasonably explained by the increased dislocation accommodation ability due to the formed nanotwins and the decreased induced dislocation proliferation.展开更多
Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has...Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has been verified to evaluate the performance of FENTs,but until recently,the response time,another crucial indicator,has been ignored.Employing finite-element method,we investigated the relationship among gate charge,switching ratio and response time by divisionally manipulating gate charge,including entrance surface and the surface of confinement space,for ion transport to optimize switching capability.The dual-split gate charge on FENTs exhibits synergistic effect on switching response.Based on the two regional gate charge on FENTs,multivalence ions in lower concentration,high aspect ratio and single channel show higher switching ratio but longer response time compared to monovalent ions.The findings highlight the necessity of balancing these two signals in FENTs and offer insights for optimizing their design and expanding applications to dual-signal-detection iontronics.展开更多
Samarium–cobalt rare-earth（Sm–Co-RE） permanent magnetic materials with large magnetic energy product, high coercive force, high Curie temperature, good thermal stability, and corrosion resistance, have wide potent...Samarium–cobalt rare-earth（Sm–Co-RE） permanent magnetic materials with large magnetic energy product, high coercive force, high Curie temperature, good thermal stability, and corrosion resistance, have wide potential applications in aerospace, microwave communications, instrumentation, electrical engineering, magnetic machinery, etc. In this paper, the development of Sm–CoRE permanent magnetic materials in the following aspects in recent years was summarized： Sm–Co-RE permanent magnets with high application temperatures, positive temperature coefficients of coercive force, zero temperature coefficients of residual magnetization, high resistance rate,high mechanical property, and nanocrystallization.展开更多
Bi_(2)S_(3)is composed of inexpensive and environ-mental friendliness elements,which has received extensive interests and been investigated as a promising mid-tempera-ture thermoelectric material for years.Even pure B...Bi_(2)S_(3)is composed of inexpensive and environ-mental friendliness elements,which has received extensive interests and been investigated as a promising mid-tempera-ture thermoelectric material for years.Even pure Bi_(2)S_(3)pos-sesses a high Seebeck coefficient and low thermal conductivity,its low electrical conductivity leads to a lowfigure of merit(ZT)value.In this work,Bi_(2)S_(3)fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl_(3).Cu interstitial doping and Cl substitution on S site result in a large increase in electrical conductivity.Additionally,the enhanced phonon scattering is derived from the point defects caused by element doping,the grain boundaries,and the small amount of sec-ondary phase,which leads to the low thermal conductivity.Finally,a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature(RT)to 773 K for the Cu-interstitial-doped and BiCl_(3)-alloyed(Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3))sample.Furthermore,the mechanical properties of the Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3)sample are lower than those of other Bi_(2)S_(3)samples,which stem from the weak chemical bonding strength.展开更多
The hybrid functionally graded materials(FGM) of hydroxyapatite(HA), stainless steel 316L(SS316L) and carbon nanotubes(CNT) were synthesized for biomedical implants. Three different types of FGM were produced by the c...The hybrid functionally graded materials(FGM) of hydroxyapatite(HA), stainless steel 316L(SS316L) and carbon nanotubes(CNT) were synthesized for biomedical implants. Three different types of FGM were produced by the combination of SS316 L and CNT to reinforce HA in discrete layers of FGM. In the first type of FGM, concentration of SS316 L was varied from 10% to 40%(mass fraction) with an increment of 10% to reinforce micro HA. In the second type of FGM, 0.5%(mass fraction) functionalized CNT was added by maintaining the rest of composition as that of the first type of FGM. In the third type of FGM, mixture of micro and nano HA(mass ratio1:1) was used, keeping rest of composition similar to the second type of FGM. All types of FGM were subjected to uniaxial compaction and sintered by pressureless sintering technique at similar compaction and sintering parameters. The results show that the densification is enhanced with the addition of CNT and nanocrystalline HA in the FGM. Hardness and fracture toughness increase in both FGM reinforced with CNT, but the increase of the hardness and fracture toughness are more pronounced in FGM with micro and nanocrystalline HA.展开更多
The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections...The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials(1DMs) as well as twodimensional materials(2DMs).展开更多
Montmorillonite and clinoptilolite zeolite were used as representative materials to prepare calcined clay-cement binary cementitious materials in order to study the effect of calcination treatment on the activation of...Montmorillonite and clinoptilolite zeolite were used as representative materials to prepare calcined clay-cement binary cementitious materials in order to study the effect of calcination treatment on the activation of clay minerals and the activity difference between layered and framed clays in this research.The influence of different calcined clay content(2%,4%,6%,8%,10%)on the fluidity,compressive strength,microstructure,phase change,and hydration heat of cement-based materials were analyzed.The calcined clay improves the fluidity of cement-based materials as compared with the uncalcined group.The addition of calcined montmorillonite(CMT)improves the development of mechanical strength,and the optimal compressive strength reaches 85 MPa at 28 days with 8%CMT.However,the activity of calcined clinoptilolite zeolite(CZL)is weak with few reaction sites,which slightly reduced the mechanical strength as compared to the blank sample.The addition of CMT changes the microscopic morphology of hydration products such as C-S-H and C-A-H,leading to the formation and transformation of ettringite in the early stage.It promotes the gradual polymerization of Si-O bonds into Si-O-Si bonds simultaneously,which accelerates the early hydration process.However,CZL acts mainly as a filling function in the cementitious system.In brief,CMT as an admixture can improve the mechanical properties of cement,but CZL has little effect.This work provides a guideline for the applications of calcined clay in cement,considering the influence of clay type on workability and mechanical strength.展开更多
In this study,the workability and reaction mechanism of metakaolin(MK)based geopolymer blended with rice husk ash(RHA)and silica fume(SF)was investigated.The prepared samples were subjected to tests including compress...In this study,the workability and reaction mechanism of metakaolin(MK)based geopolymer blended with rice husk ash(RHA)and silica fume(SF)was investigated.The prepared samples were subjected to tests including compressive strength and fluidity tests.X-ray diffraction(XRD)and Scanning electron microscope(SEM)were employed to explore the phase composition and microstructure of geopolymers.The molecular bonding information of geopolymer was provided by Fourier transform infrared spectroscopy(FTIR).Meanwhile,the porosity of geopolymer was obtained by Mercury intrusion porosimeter(MIP)analysis.The high-activity RHA obtained after calcination at 600℃ was used as a supplementary cementitious material to prepare geopolymer.The properties of preventing morphology cracking and compressive strength are improved.The addition of RHA and SF changes the working performance of MK based geopolymer and provided a theoretical basis for future practical applications.Meanwhile,the high chemical activity of SF and RHA contributes to the healing of microcracks.展开更多
Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transfor...Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products.展开更多
The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium alloys.In this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent...The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium alloys.In this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent heat treatment at 300,450,and 500°C.The material properties of the resulting samples were assessed through microstructural observation,tensile testing,electrical conductivity measurements,and electromagnetic shielding effectiveness(EMI-SE)testing.The influence of the Mg-8Li-3Y-2Zn alloy microstructure on its mechanical and electromagnetic shielding properties in different states was investigated.It was found that the as-cast alloy containsα-Mg,β-Li,Mg_(3)Zn_(3)Y_(2),and Mg_(12)ZnY phases.Following heat treatment at 500℃(HT500),the blockα-Mg phase transformedfine needle-shapes,its tensile strength increased to 263.7 MPa,and its elongation reached 45.3%.The mechanical properties of the alloy were significantly improved by the synergistic effects imparted by the needle-shapedα-Mg phase,solid solution strengthening,and precipitation strengthening.The addition of Y and Zn improved the EMI-SE of Mg-8Li-1Zn alloy,wherein the HT500 sample exhibits the highest SE,maintaining a value of 106.7–76.9 dB in the frequency range of 30–4500 MHz;this performance has rarely been reported for electromagnetically shielded alloys.This effect was mainly attributed to the multiple reflections of electromagnetic waves caused by the severe impedance mismatch of the abundant phase boundaries,which were in turn provided by the dual-phase(α/β)and secondary phases.Furthermore,the presence of nano-precipitation was also believed to enhance the absorption of electromagnetic waves.展开更多
Finding materials with specific properties is a hot topic in materials science.Traditional materials design relies on empirical and trial-and-error methods,requiring extensive experiments and time,resulting in high co...Finding materials with specific properties is a hot topic in materials science.Traditional materials design relies on empirical and trial-and-error methods,requiring extensive experiments and time,resulting in high costs.With the development of physics,statistics,computer science,and other fields,machine learning offers opportunities for systematically discovering new materials.Especially through machine learning-based inverse design,machine learning algorithms analyze the mapping relationships between materials and their properties to find materials with desired properties.This paper first outlines the basic concepts of materials inverse design and the challenges faced by machine learning-based approaches to materials inverse design.Then,three main inverse design methods—exploration-based,model-based,and optimization-based—are analyzed in the context of different application scenarios.Finally,the applications of inverse design methods in alloys,optical materials,and acoustic materials are elaborated on,and the prospects for materials inverse design are discussed.The authors hope to accelerate the discovery of new materials and provide new possibilities for advancing materials science and innovative design methods.展开更多
Electrocatalytic CO_(2)reduction(ECR)to produce value-added fuels and chemicals using renewable electricity is an emerging strategy to mitigate global warming and decrease reliance on fossil fuels.Among various ECR pr...Electrocatalytic CO_(2)reduction(ECR)to produce value-added fuels and chemicals using renewable electricity is an emerging strategy to mitigate global warming and decrease reliance on fossil fuels.Among various ECR products,liquid oxygenates(Oxys)are especially attractive due to their high energy density,high safety and transportability that could be adapted to the existing infrastructure and transportation system.However,efficiently generating these highly reduced oxygen-containing products by ECR remains challenging due to the complexity of coupled proton and electron transfer processes.In recent years,in-depth studies of reaction mechanisms have advanced the design of catalysts and the regulation of reaction systems for ECR to produce Oxys,Here,by focusing on the production of typical Oxys,such as methanol,acetic acid,ethanol,acetone,n-propanol,and isopropanol,we outline various reaction paths and key intermediates for the electrochemical conversion of CO_(2)into these target products.We also summarize the current research status and recent advances in catalysts based on their elemental composition,and consider recent studies on the change of catalyst geometry and electronic structure,as well as the optimization of reaction systems to increase ECR performance.Finally,we analyze the challenges in the field of ECR to Oxys and provide an outlook on future directions for high-efficiency catalyst prediction and design,as well as the development of advanced reaction systems.展开更多
Reinforcing metal matrix composites(MMCs)with nanophases of distinct characteristics is an effective strategy for utilizing their individual advantages and achieving superior properties of the composite.In this study,...Reinforcing metal matrix composites(MMCs)with nanophases of distinct characteristics is an effective strategy for utilizing their individual advantages and achieving superior properties of the composite.In this study,a combination of molecular level mixing(MLM),segment ball milling(SBM),and in-situ solid-phase reaction was employed to fabricate Cu matrix composites(TiC-CNT/Cu)reinforced with TiC decorated CNT(TiC@CNT)and in-situ nanoscale TiC particles.The HRTEM results revealed the epitaxial growth of interfacial TiC on the surface of CNT(i.e.,CNT(0002)//TiC(200),and the formation of a semi-coherent interface between TiC and Cu matrix,which can effectively enhance the interfacial bonding strength and optimize load transfer efficiency of CNT.The independent in-situ TiC nanoparticles got into the grain interior through grain boundary migration,thereby significantly enhancing both strain hardening capacity and strength of the composite by fully utilizing the Orowan strengthening mechanism.Moreover,the enhanced bonding strength of the interface can also effectively suppress crack initiation and propagation,thereby improving the fracture toughness of the composite.The TiC-CNT/Cu composite with 1.2 vol.%CNT exhibited a tensile strength of 372 MPa,achieving a super high strengthening efficiency of 270,while simultaneously maintaining a remarkable ductility of 21.2%.Furthermore,the impact toughness of the TiC-CNT/Cu composite exhibited a significant enhancement of 70.7%compared to that of the CNT/Cu composite,reaching an impressive value of 251 kJ/m^(2),thereby demonstrating exceptional fracture toughness.Fully exploiting the synergistic strengthening effect of different nanophases can be an effective way to improve the comprehensive properties of MMCs.展开更多
In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-c...In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-cation perovskites(MCPs) have been extensively used as absorber thin films in perovskite solar cells(PSCs), achieving high power conversion efficiencies(PCE) over 26%^([1, 2]).展开更多
Ferroelastic rare earth tantalates(RETaO_(4))are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO_(4)powders are hugely significant for synthesizing their coatings.The current research...Ferroelastic rare earth tantalates(RETaO_(4))are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO_(4)powders are hugely significant for synthesizing their coatings.The current research used chemical co-precipitation within an automated experimental device to synthesize RETaO_(4)(RE=Nd,Sm,Gd,Ho,Er)powders.The device automatically monitored and controlled the solutions'pH,improving the chemical co-precipitation efficiency.The crystal structure and microstructure of the RETaO_(4)powders can be controlled by changing the annealing temperature,and the materials undergo an m'-m phase transition.The m'-RETaO_(4)powders exhibit nano-size grains,while m-RETaO_(4)powders evince micron-size grains,altered by the annealing temperatures.A simultaneous thermal analysis es-timates the reversive ferroelastic tetragonal-monoclinic phase transition temperatures.Overall,this research focuses on the synthesis,crystal structures,microstructures,and phase transition of the fabricated RETaO_(4)powders.展开更多
Thermal and mechanical properties of yttrium tantalate(YTaO_(4)),a top coat ceramic of thermal barrier coatings(TBCs)for aeroengines,are enhanced by synthesizing Y_(1-x)Ta_(1-x)M_(2x)O_(4)(M=Ti,Zr,Hf;x=0.06,0.12,0.18,...Thermal and mechanical properties of yttrium tantalate(YTaO_(4)),a top coat ceramic of thermal barrier coatings(TBCs)for aeroengines,are enhanced by synthesizing Y_(1-x)Ta_(1-x)M_(2x)O_(4)(M=Ti,Zr,Hf;x=0.06,0.12,0.18,0.24)medium-entropy ceramics(MECs)using a two-step sintering method.In addition,the thermal conductivity,thermal expansion coefficients(TECs),and fracture toughness of MECs were investigated.An X-ray diffraction study revealed that the Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs were monoclinic,and the Ti,Zr,and Hf doping elements replaced Y and Ta.The variations in atomic weights and ionic radii led to disturbed atomic arrangements and severe lattice distortions,resulting in improving the phonon scattering and reduced thermal conductivity,with Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)exhibiting the lowest thermal conductivity of 1.23 W·m^(-1)·K^(-1)at 900℃.The introduction of MO_(2) increased the configurational entropy and weakened the ionic bonding energy,obtaining high TECs(10.4×10^(-6)K^(-1)at 1400℃).The reduction in the monoclinic angle β lowered the ferroelastic domain inversion energy barrier.Moreover,microcracks and crack extension toughening endowed Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)with the highest fracture toughness of(4.1±0.5)MPa·m~(1/2).The simultaneous improvement of the thermal and mechanical properties of the MO_(2)(M=Ti,Zr,Hf)co-doped YTaO_(4) MECs can be extended to other materials.展开更多
Graphite-silicon species(Gr-Si)hybrid anodes have merged as potential candidates for high-energy lithium-ion batteries(LIBs),yet long been plagued by rapid capacity fading due to their unstable mechano-electrochemistr...Graphite-silicon species(Gr-Si)hybrid anodes have merged as potential candidates for high-energy lithium-ion batteries(LIBs),yet long been plagued by rapid capacity fading due to their unstable mechano-electrochemistry.The dominant approach to enhance electrochemical stability of the Gr-Si hybrid anodes typically involves the optimization of the electrode material structures and the employment of low active Si species content in electrode(<10 wt%in most instances).However,the electrode structure design,a factor of equal importance in determining the electrochemical performance of Gr-Si hybrid anodes,has received scant attention.In this study,three Gr-Si hybrid anodes with the identical material composition but distinct electrode structures are designed to investigate the mechanoelectrochemistry of the electrodes.It is revealed that the substantial volume change of Si species particles in Gr-Si hybrid anodes led to the local lattice stress of Gr at their contact interface during the charge/discharge processes,thereby increasing thermodynamic and kinetic barrier of Li-ion migration.Furthermore,the huge disparity in volume change of Si species and Gr particles trigger the separate agglomeration of these two materials,resulting in a considerable electrode volume change and increased electrochemical resistance.An advanced Gr/Si hybrid anode with upper Gr and lower Si species layer structure design addresses the above challenges using photovoltaic waste silicon sources under high Si species content(17 wt%)and areal capacity(2.0 mA h cm^(-2))in Ah-level full pouch cells with a low negative/positive(N/P)ratio of 1.09.The cell shows stable cycling for 100 cycles at 0.3 C with an impressively low capacity decay rate of 0.0546%per cycle,outperforming most reported Gr-Si hybrid anodes.展开更多
基金supported by the SP2024/089 Project by the Faculty of Materials Science and Technology,VˇSB-Technical University of Ostrava.
文摘In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable solutions.Nevertheless,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely explored.This study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic materials.The ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree Regression(DTR),and Gaussian Process Regression(GPR)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon steel.Although the GPR method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.
基金financially supported by the Program of the National Natural Science Foundation of China(No.22209067)Stable Support Plan Program for Higher Education Institutions(No.20220814235931001)+4 种基金Shenzhen Science and Technology Program(No.KQTD20200820113047086)supported by XXX-Project(No.2020-XXXX-XX-246-00)supported by the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(No.22hytd01)supported by 21C Innovation Laboratory,Contemporary Amperex Technology Ltd.(No.C-ND-21C LAB-210044-1.0)by Center for Computational Science and Engineering at Southern University of Science and Technology。
文摘Anti-perovskite cathodes,typified by Li_(2)FeSO,hold great promise for Li-ion batteries due to their high specific capacity,cost-effectiveness,and ease of production.However,their utilization in high-energydensity batteries is hindered by low Li intercalation voltage and limited rate performance.This study employs first-principles calculations to assess the impact of element substitutions and doping on the voltage and Li-ion migration energy barrier in Li_(2)TMSO(TM=Cu,Ni,Co,Fe,V,Cr,Ti)anti-perovskite materials.Our findings reveal that replacing the S element with Se or Te in Li_(2)FeSO and Li_(2)MnSO can reduce the voltage.For Li_(2)TMSO(TM=Cu,Ni,Co,Fe,V,Cr,Ti),the voltage increases as TM changes from Ti to Ni.This process closely related to the downward shift of the TM-3d electron orbital energy level.When the energy level difference between TM-3d and S-3p orbital energy levels is large,the voltage is determined by TM-3d orbitals.When the difference is small,S-3p participates in the reaction.Additionally,doping with the inactive element Mg could allow deeper energy level electrons to participate in the reaction,thus increasing the voltage.To simultaneously enhance intercalation voltage and rate performance,we investigated multi-element doping strategies for anti-perovskite cathode materials.Our study establishes a solid foundation the development of high-voltage anti-perovskite cathodes,holding promise for significant advancements in energy storage technology.
基金funded by the National Natural Science Foundation of China (52061020).
文摘Quantitative analysis of aluminum-silicon(Al-Si)alloy microstructure is crucial for evaluating and controlling alloy performance.Conventional analysis methods rely on manual segmentation,which is inefficient and subjective,while fully supervised deep learning approaches require extensive and expensive pixel-level annotated data.Furthermore,existing semi-supervised methods still face challenges in handling the adhesion of adjacent primary silicon particles and effectively utilizing consistency in unlabeled data.To address these issues,this paper proposes a novel semi-supervised framework for Al-Si alloy microstructure image segmentation.First,we introduce a Rotational Uncertainty Correction Strategy(RUCS).This strategy employs multi-angle rotational perturbations andMonte Carlo sampling to assess prediction consistency,generating a pixel-wise confidence weight map.By integrating this map into the loss function,the model dynamically focuses on high-confidence regions,thereby improving generalization ability while reducing manual annotation pressure.Second,we design a Boundary EnhancementModule(BEM)to strengthen boundary feature extraction through erosion difference and multi-scale dilated convolutions.This module guides the model to focus on the boundary regions of adjacent particles,effectively resolving particle adhesion and improving segmentation accuracy.Systematic experiments were conducted on the Aluminum-Silicon Alloy Microstructure Dataset(ASAD).Results indicate that the proposed method performs exceptionally well with scarce labeled data.Specifically,using only 5%labeled data,our method improves the Jaccard index and Adjusted Rand Index(ARI)by 2.84 and 1.57 percentage points,respectively,and reduces the Variation of Information(VI)by 8.65 compared to stateof-the-art semi-supervised models,approaching the performance levels of 10%labeled data.These results demonstrate that the proposed method significantly enhances the accuracy and robustness of quantitative microstructure analysis while reducing annotation costs.
基金financially supported by the Fundamental Research Funds for the Central Universities,China(No.21624408)the Guangdong Basic and Applied Basic Research Foundation,China(Nos.2023A1515012850,2024A1515010416)+2 种基金Guangzhou Science and Technology Planning Project,China(No.2024A04J9966)the National Natural Science Foundation of China(Nos.52271132,52004101)the Key Laboratory of Advanced Materials of Yunnan Province,China(No.2024KF02)。
文摘To exploit the combined strengthening effects of nanotwins and carbon nanotubes(CNTs)in Cu matrix composites,the nanotwins with a width ranging from 3 to 30 nm were incorporated into the CNTs-reinforced Cu matrix composites using cryogenic rolling and optimizing the initial particle size of the raw Cu powders.The formation of nanotwins in the Cu matrix composite reinforced by only 0.2 wt.%CNTs is accompanied by the increased dislocation density and refined Cu grain size,resulting in much better strength−ductility synergy than the referenced composite without significant nanotwins formation.The analysis of strengthening and toughening mechanisms demonstrates that the strength increment mainly derives from grain refinement strengthening,dislocation strengthening,and nanotwin strengthening.The strength increment from the contribution of the nanotwins accounts for 19.9%of the overall strength increment for the composite.Meanwhile,the retention of good tensile ductility can be reasonably explained by the increased dislocation accommodation ability due to the formed nanotwins and the decreased induced dislocation proliferation.
基金supported by the Natural Science Foundation of Guangdong Province,China (No.2025A1515011654)the National Natural Science Foundation of China (No.22090053)+3 种基金the Fundamental Research Funds for National Universities,China University of Geosciences (Wuhan)support from the program of China Scholarships Council (No.202406410155)Young Elite Scientists Sponsorship Program by CAST-Doctoral Student Special Plansupport from the S&T Special Program of Huzhou (No.2024GZ07)。
文摘Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has been verified to evaluate the performance of FENTs,but until recently,the response time,another crucial indicator,has been ignored.Employing finite-element method,we investigated the relationship among gate charge,switching ratio and response time by divisionally manipulating gate charge,including entrance surface and the surface of confinement space,for ion transport to optimize switching capability.The dual-split gate charge on FENTs exhibits synergistic effect on switching response.Based on the two regional gate charge on FENTs,multivalence ions in lower concentration,high aspect ratio and single channel show higher switching ratio but longer response time compared to monovalent ions.The findings highlight the necessity of balancing these two signals in FENTs and offer insights for optimizing their design and expanding applications to dual-signal-detection iontronics.
基金financially supported by the Research Fund for the Doctoral Program of Higher Education of China (No.20100560)the National Natural Science Foundation of China (Nos. 51104188 and 51274107)
文摘Samarium–cobalt rare-earth（Sm–Co-RE） permanent magnetic materials with large magnetic energy product, high coercive force, high Curie temperature, good thermal stability, and corrosion resistance, have wide potential applications in aerospace, microwave communications, instrumentation, electrical engineering, magnetic machinery, etc. In this paper, the development of Sm–CoRE permanent magnetic materials in the following aspects in recent years was summarized： Sm–Co-RE permanent magnets with high application temperatures, positive temperature coefficients of coercive force, zero temperature coefficients of residual magnetization, high resistance rate,high mechanical property, and nanocrystallization.
基金financially supported by the National Natural Science Foundation of China (No. 11764025)the Academician (Expert) Workstation of Yunnan Province Program (No. 202005AF150010)Yunnan Provincial Natural Science Key Fund (No. 202101AS070015)。
文摘Bi_(2)S_(3)is composed of inexpensive and environ-mental friendliness elements,which has received extensive interests and been investigated as a promising mid-tempera-ture thermoelectric material for years.Even pure Bi_(2)S_(3)pos-sesses a high Seebeck coefficient and low thermal conductivity,its low electrical conductivity leads to a lowfigure of merit(ZT)value.In this work,Bi_(2)S_(3)fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl_(3).Cu interstitial doping and Cl substitution on S site result in a large increase in electrical conductivity.Additionally,the enhanced phonon scattering is derived from the point defects caused by element doping,the grain boundaries,and the small amount of sec-ondary phase,which leads to the low thermal conductivity.Finally,a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature(RT)to 773 K for the Cu-interstitial-doped and BiCl_(3)-alloyed(Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3))sample.Furthermore,the mechanical properties of the Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3)sample are lower than those of other Bi_(2)S_(3)samples,which stem from the weak chemical bonding strength.
基金GIK Institute for financial assistance and providing research facilitiessupported by the Basic Research program through the National Research Foundation of Korea (NRF) funded by Ministry, Science and Technology (MEST) (2011-0030058)
文摘The hybrid functionally graded materials(FGM) of hydroxyapatite(HA), stainless steel 316L(SS316L) and carbon nanotubes(CNT) were synthesized for biomedical implants. Three different types of FGM were produced by the combination of SS316 L and CNT to reinforce HA in discrete layers of FGM. In the first type of FGM, concentration of SS316 L was varied from 10% to 40%(mass fraction) with an increment of 10% to reinforce micro HA. In the second type of FGM, 0.5%(mass fraction) functionalized CNT was added by maintaining the rest of composition as that of the first type of FGM. In the third type of FGM, mixture of micro and nano HA(mass ratio1:1) was used, keeping rest of composition similar to the second type of FGM. All types of FGM were subjected to uniaxial compaction and sintered by pressureless sintering technique at similar compaction and sintering parameters. The results show that the densification is enhanced with the addition of CNT and nanocrystalline HA in the FGM. Hardness and fracture toughness increase in both FGM reinforced with CNT, but the increase of the hardness and fracture toughness are more pronounced in FGM with micro and nanocrystalline HA.
基金supported by the National Natural Science Foundation of China (Nos. 21525523, 21722507, 21574048, 21874121)the National Basic Research Program of China (973 Program, No. 2015CB932600)+1 种基金the National Key R&D Program of China (Nos. 2017YFA020800, 2016YFF0100800)Natural Science Foundation of Zhejiang Province of China (No. LY18B050002)
文摘The complexity of biological samples determines that the detection of a single biomolecule is unable to satisfy actual needs. Moreover, the "false positives" results caused by a single biomolecule detections easily leads to erroneous clinical diagnosis and treatment. Thus, it is important for the homogenous quantification of multiple biomolecules in not only basic research but also practical application. As a consequent, a large number of literatures have been exploited to monitor multiple biomolecules in homogenous solution, enabling facilitating the development of the disease diagnosis, treatment as well as drug discovery. One-dimensional nanomaterials and two-dimensional nanomaterials have special physical and chemical properties, such as good electrochemical properties, stable structure, large specific surface area, and biocompatibility, which are widely used in electrochemical and fluorescent detection of biomolecules. This tutorial review highlights the recent development for the detection of multiple biomolecules by using nanomaterials including one-dimensional materials(1DMs) as well as twodimensional materials(2DMs).
基金The research presented in this paper was supported by National Natural Science Foundation of China(Grant No.52272031)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan),and the Opening Fund of Guangxi Key Laboratory of New Energy and Building Energy Saving(Grant No.19-J-22-2)+3 种基金Key Research and Development Program of Hubei Province(Grant No.2020BAB065)Key Research and Development Program of Jiangxi Province(Grant No.20201BBG71011)Fundamental Research Funds for the Central Universities,CHD(Grant No.300102211506)Opening Fund of Key Laboratory of Advanced Building Materials of Anhui Province(Grant No.JZCL001KF).
文摘Montmorillonite and clinoptilolite zeolite were used as representative materials to prepare calcined clay-cement binary cementitious materials in order to study the effect of calcination treatment on the activation of clay minerals and the activity difference between layered and framed clays in this research.The influence of different calcined clay content(2%,4%,6%,8%,10%)on the fluidity,compressive strength,microstructure,phase change,and hydration heat of cement-based materials were analyzed.The calcined clay improves the fluidity of cement-based materials as compared with the uncalcined group.The addition of calcined montmorillonite(CMT)improves the development of mechanical strength,and the optimal compressive strength reaches 85 MPa at 28 days with 8%CMT.However,the activity of calcined clinoptilolite zeolite(CZL)is weak with few reaction sites,which slightly reduced the mechanical strength as compared to the blank sample.The addition of CMT changes the microscopic morphology of hydration products such as C-S-H and C-A-H,leading to the formation and transformation of ettringite in the early stage.It promotes the gradual polymerization of Si-O bonds into Si-O-Si bonds simultaneously,which accelerates the early hydration process.However,CZL acts mainly as a filling function in the cementitious system.In brief,CMT as an admixture can improve the mechanical properties of cement,but CZL has little effect.This work provides a guideline for the applications of calcined clay in cement,considering the influence of clay type on workability and mechanical strength.
基金The research presented in this paper was supported by Natural Science Foundation of Hubei Province(No.2020CFB575)Natural Science Foundation of Zhejiang Province(No.LY19E080003)+5 种基金the Opening Fund of Key Laboratory of Geological Survey and Evaluation of Ministry of Education(Grant No.GLAB2020ZR09)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)and the Opening Fund of Guangxi Key Laboratory of New Energy and Building Energy Saving(Grant No.19-J-22-2)Key Research and Development Program of Hubei Province(Grant No.2020BAB065)Key Research and Development Program of Jiangxi Province(Grant No.20201BBG71011)Fundamental Research Funds for the Central Universities,CHD(Grant No.300102211506)Opening Fund of Key Laboratory of Advanced Building Materials of Anhui Province(Grant No.JZCL001KF).
文摘In this study,the workability and reaction mechanism of metakaolin(MK)based geopolymer blended with rice husk ash(RHA)and silica fume(SF)was investigated.The prepared samples were subjected to tests including compressive strength and fluidity tests.X-ray diffraction(XRD)and Scanning electron microscope(SEM)were employed to explore the phase composition and microstructure of geopolymers.The molecular bonding information of geopolymer was provided by Fourier transform infrared spectroscopy(FTIR).Meanwhile,the porosity of geopolymer was obtained by Mercury intrusion porosimeter(MIP)analysis.The high-activity RHA obtained after calcination at 600℃ was used as a supplementary cementitious material to prepare geopolymer.The properties of preventing morphology cracking and compressive strength are improved.The addition of RHA and SF changes the working performance of MK based geopolymer and provided a theoretical basis for future practical applications.Meanwhile,the high chemical activity of SF and RHA contributes to the healing of microcracks.
文摘Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products.
基金supported by the National Natural Sci-ence Foundation of China[No.51564032]Yunnan Provin-cial Department of Education Science Research Fund Project[KKPH202132005]the Analysis and Testing Founda-tion of Kunming University of Science and Technology[2022M20212130086].
文摘The performances of magnesium alloys remain insufficient to further enhance the application potential of ultralight magnesium alloys.In this work,a Mg-8Li-3Y-2Zn alloy was prepared through vacuum melting and subsequent heat treatment at 300,450,and 500°C.The material properties of the resulting samples were assessed through microstructural observation,tensile testing,electrical conductivity measurements,and electromagnetic shielding effectiveness(EMI-SE)testing.The influence of the Mg-8Li-3Y-2Zn alloy microstructure on its mechanical and electromagnetic shielding properties in different states was investigated.It was found that the as-cast alloy containsα-Mg,β-Li,Mg_(3)Zn_(3)Y_(2),and Mg_(12)ZnY phases.Following heat treatment at 500℃(HT500),the blockα-Mg phase transformedfine needle-shapes,its tensile strength increased to 263.7 MPa,and its elongation reached 45.3%.The mechanical properties of the alloy were significantly improved by the synergistic effects imparted by the needle-shapedα-Mg phase,solid solution strengthening,and precipitation strengthening.The addition of Y and Zn improved the EMI-SE of Mg-8Li-1Zn alloy,wherein the HT500 sample exhibits the highest SE,maintaining a value of 106.7–76.9 dB in the frequency range of 30–4500 MHz;this performance has rarely been reported for electromagnetically shielded alloys.This effect was mainly attributed to the multiple reflections of electromagnetic waves caused by the severe impedance mismatch of the abundant phase boundaries,which were in turn provided by the dual-phase(α/β)and secondary phases.Furthermore,the presence of nano-precipitation was also believed to enhance the absorption of electromagnetic waves.
基金funded by theNationalNatural Science Foundation of China(52061020)Major Science and Technology Projects in Yunnan Province(202302AG050009)Yunnan Fundamental Research Projects(202301AV070003).
文摘Finding materials with specific properties is a hot topic in materials science.Traditional materials design relies on empirical and trial-and-error methods,requiring extensive experiments and time,resulting in high costs.With the development of physics,statistics,computer science,and other fields,machine learning offers opportunities for systematically discovering new materials.Especially through machine learning-based inverse design,machine learning algorithms analyze the mapping relationships between materials and their properties to find materials with desired properties.This paper first outlines the basic concepts of materials inverse design and the challenges faced by machine learning-based approaches to materials inverse design.Then,three main inverse design methods—exploration-based,model-based,and optimization-based—are analyzed in the context of different application scenarios.Finally,the applications of inverse design methods in alloys,optical materials,and acoustic materials are elaborated on,and the prospects for materials inverse design are discussed.The authors hope to accelerate the discovery of new materials and provide new possibilities for advancing materials science and innovative design methods.
基金financial supports from the National Natural Science Foundation of China(52201237)the Talent Introduction Project of Chinese Academy of Sciences(E344011)+4 种基金the Shenzhen High Level Talent Team Project(KQTD2022110109364705)the Joint Research Project of China Merchants Group and SIAT(E2Z1521)the Cross Institute Joint Research Youth Team Project of SIAT(E25427)National Natural Science Foundation of China(52402136)the China Postdoctoral Science Foundation(E325281005)。
文摘Electrocatalytic CO_(2)reduction(ECR)to produce value-added fuels and chemicals using renewable electricity is an emerging strategy to mitigate global warming and decrease reliance on fossil fuels.Among various ECR products,liquid oxygenates(Oxys)are especially attractive due to their high energy density,high safety and transportability that could be adapted to the existing infrastructure and transportation system.However,efficiently generating these highly reduced oxygen-containing products by ECR remains challenging due to the complexity of coupled proton and electron transfer processes.In recent years,in-depth studies of reaction mechanisms have advanced the design of catalysts and the regulation of reaction systems for ECR to produce Oxys,Here,by focusing on the production of typical Oxys,such as methanol,acetic acid,ethanol,acetone,n-propanol,and isopropanol,we outline various reaction paths and key intermediates for the electrochemical conversion of CO_(2)into these target products.We also summarize the current research status and recent advances in catalysts based on their elemental composition,and consider recent studies on the change of catalyst geometry and electronic structure,as well as the optimization of reaction systems to increase ECR performance.Finally,we analyze the challenges in the field of ECR to Oxys and provide an outlook on future directions for high-efficiency catalyst prediction and design,as well as the development of advanced reaction systems.
基金financially supported by the National Natural Science Foundation of China(No.52371136)the Yunnan Provincial Science and Technology Department(No.202202AG050004).
文摘Reinforcing metal matrix composites(MMCs)with nanophases of distinct characteristics is an effective strategy for utilizing their individual advantages and achieving superior properties of the composite.In this study,a combination of molecular level mixing(MLM),segment ball milling(SBM),and in-situ solid-phase reaction was employed to fabricate Cu matrix composites(TiC-CNT/Cu)reinforced with TiC decorated CNT(TiC@CNT)and in-situ nanoscale TiC particles.The HRTEM results revealed the epitaxial growth of interfacial TiC on the surface of CNT(i.e.,CNT(0002)//TiC(200),and the formation of a semi-coherent interface between TiC and Cu matrix,which can effectively enhance the interfacial bonding strength and optimize load transfer efficiency of CNT.The independent in-situ TiC nanoparticles got into the grain interior through grain boundary migration,thereby significantly enhancing both strain hardening capacity and strength of the composite by fully utilizing the Orowan strengthening mechanism.Moreover,the enhanced bonding strength of the interface can also effectively suppress crack initiation and propagation,thereby improving the fracture toughness of the composite.The TiC-CNT/Cu composite with 1.2 vol.%CNT exhibited a tensile strength of 372 MPa,achieving a super high strengthening efficiency of 270,while simultaneously maintaining a remarkable ductility of 21.2%.Furthermore,the impact toughness of the TiC-CNT/Cu composite exhibited a significant enhancement of 70.7%compared to that of the CNT/Cu composite,reaching an impressive value of 251 kJ/m^(2),thereby demonstrating exceptional fracture toughness.Fully exploiting the synergistic strengthening effect of different nanophases can be an effective way to improve the comprehensive properties of MMCs.
基金financially supported by the National Natural Science Foundation of China (52462032, 62274018, 52462031)Natural Science Foundation of Yunnan Province (202501AT070353, 202101BE070001-049)+2 种基金the Xinjiang Construction Corps Key Areas of Science and Technology Research Project (2023AB029)the Tianchi Talent Program of Xinjiang Uygur Autonomous Region (2024, Jiangzhao Chen)the Key Project of Chongqing Overseas Students Returning to China Entrepreneurship and Innovation Support Plan (cx2023006)。
文摘In recent years, the research advancements have high-lighted the critical role of the A-site cation in determining the optoelectronic and physicochemical properties of organicinorganic lead halide perovskites. Mixed-cation perovskites(MCPs) have been extensively used as absorber thin films in perovskite solar cells(PSCs), achieving high power conversion efficiencies(PCE) over 26%^([1, 2]).
基金the Rare and Precious Metals Material Genetic Engineering Project of Yunnan Province(202102AB080019-1)National Key Research and Development Program of China(2022YFB3708600)the National Natural Science Foundation of China(91960103).
文摘Ferroelastic rare earth tantalates(RETaO_(4))are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO_(4)powders are hugely significant for synthesizing their coatings.The current research used chemical co-precipitation within an automated experimental device to synthesize RETaO_(4)(RE=Nd,Sm,Gd,Ho,Er)powders.The device automatically monitored and controlled the solutions'pH,improving the chemical co-precipitation efficiency.The crystal structure and microstructure of the RETaO_(4)powders can be controlled by changing the annealing temperature,and the materials undergo an m'-m phase transition.The m'-RETaO_(4)powders exhibit nano-size grains,while m-RETaO_(4)powders evince micron-size grains,altered by the annealing temperatures.A simultaneous thermal analysis es-timates the reversive ferroelastic tetragonal-monoclinic phase transition temperatures.Overall,this research focuses on the synthesis,crystal structures,microstructures,and phase transition of the fabricated RETaO_(4)powders.
文摘Thermal and mechanical properties of yttrium tantalate(YTaO_(4)),a top coat ceramic of thermal barrier coatings(TBCs)for aeroengines,are enhanced by synthesizing Y_(1-x)Ta_(1-x)M_(2x)O_(4)(M=Ti,Zr,Hf;x=0.06,0.12,0.18,0.24)medium-entropy ceramics(MECs)using a two-step sintering method.In addition,the thermal conductivity,thermal expansion coefficients(TECs),and fracture toughness of MECs were investigated.An X-ray diffraction study revealed that the Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs were monoclinic,and the Ti,Zr,and Hf doping elements replaced Y and Ta.The variations in atomic weights and ionic radii led to disturbed atomic arrangements and severe lattice distortions,resulting in improving the phonon scattering and reduced thermal conductivity,with Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)exhibiting the lowest thermal conductivity of 1.23 W·m^(-1)·K^(-1)at 900℃.The introduction of MO_(2) increased the configurational entropy and weakened the ionic bonding energy,obtaining high TECs(10.4×10^(-6)K^(-1)at 1400℃).The reduction in the monoclinic angle β lowered the ferroelastic domain inversion energy barrier.Moreover,microcracks and crack extension toughening endowed Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)with the highest fracture toughness of(4.1±0.5)MPa·m~(1/2).The simultaneous improvement of the thermal and mechanical properties of the MO_(2)(M=Ti,Zr,Hf)co-doped YTaO_(4) MECs can be extended to other materials.
基金the financial support by the National Natural Science Foundation of China(52072137)the National Natural Science Foundation of China(22205068)the"CUG Scholar"Scientific Research Funds at China University of Geosciences(Wuhan)(2022118)。
文摘Graphite-silicon species(Gr-Si)hybrid anodes have merged as potential candidates for high-energy lithium-ion batteries(LIBs),yet long been plagued by rapid capacity fading due to their unstable mechano-electrochemistry.The dominant approach to enhance electrochemical stability of the Gr-Si hybrid anodes typically involves the optimization of the electrode material structures and the employment of low active Si species content in electrode(<10 wt%in most instances).However,the electrode structure design,a factor of equal importance in determining the electrochemical performance of Gr-Si hybrid anodes,has received scant attention.In this study,three Gr-Si hybrid anodes with the identical material composition but distinct electrode structures are designed to investigate the mechanoelectrochemistry of the electrodes.It is revealed that the substantial volume change of Si species particles in Gr-Si hybrid anodes led to the local lattice stress of Gr at their contact interface during the charge/discharge processes,thereby increasing thermodynamic and kinetic barrier of Li-ion migration.Furthermore,the huge disparity in volume change of Si species and Gr particles trigger the separate agglomeration of these two materials,resulting in a considerable electrode volume change and increased electrochemical resistance.An advanced Gr/Si hybrid anode with upper Gr and lower Si species layer structure design addresses the above challenges using photovoltaic waste silicon sources under high Si species content(17 wt%)and areal capacity(2.0 mA h cm^(-2))in Ah-level full pouch cells with a low negative/positive(N/P)ratio of 1.09.The cell shows stable cycling for 100 cycles at 0.3 C with an impressively low capacity decay rate of 0.0546%per cycle,outperforming most reported Gr-Si hybrid anodes.
