A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The resu...A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction.展开更多
Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electro...Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electrolyte system that employs a low-freezing-point diluent to compress solvation sheaths,enabling the formation of a compact anion-dominated solvation structure that enhances interfacial stability and safety.Molecular dynamics reveal the unique solvation structure with close packing of anions in this low-concentration electrolyte from the micro-mesoscopic scale.The optimized electrolyte combines cost-effectiveness,superior wettability,intrinsic nonflammability,and high stability,concurrently promoting a hybrid organic-inorganic solid electrolyte interphase(SEI)and cathode electrolyte interphase(CEI)for uniform lithium deposition.As a result,the Li‖LiFePO_(4)(LFP)full cells demonstrate stable cycling for 700 cycles at the current density of 4 C.Remarkably,the electrolyte demonstrates exceptional low-temperature performance,indicating broad operational viability.This work provides a promising electrolyte design strategy that addresses both safety and excellent electrochemical performance in high-energy-density metal-based batteries,including but not restricted to Li,Na,K and Zn multivalent ion systems.展开更多
Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of ...Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of fluorine atom influences the passivation effect and para-fluorinated one provided the most substantial performance enhancement mainly originating from ameliorated contact and energy band alignment between NiOx and perovskite,improved perovskite quality and defect healing.Resultantly,PSC with a power conversion efficiency of 24%can be achieved.Meanwhile,which can maintain 96.8%of the initial PCE after a 1000 h storage,presenting enhanced durability.This work highlights the critical role of molecular functionality and conformation in the buried interface modification of PSCs,providing valuable insights for future developments.展开更多
Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inhere...Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inherent activity and incompatibility of the individual components themselves,and the irregular charge distribution and slow charge transfer ability between interfaces severely limit the activity of UOR.Therefore,we optimized and designed a Ni_(2)P/CoP interface with modulated surface charge distribution and directed charge transfer to promote UOR activity.Density functional theorycalculations first predict a regular charge transfer from CoP to Ni_(2)P,which creates a built-in electric field between Ni_(2)P and CoP interface.Optimization of the adsorption/desorption process of UOR/HER reaction intermediates leads to the improvement of catalytic activity.Electrochemical impedance spectroscopy and ex situ X-ray photoelectron spectroscopy characterization confirm the unique mechanism of facilitated reaction at the Ni_(2)P/CoP interface.Electrochemical tests further validated the prediction with excellent UOR/HER activities of 1.28 V and 19.7 mV vs.RHE,at 10 mA cm^(-2),respectively.Furthermore,Ni_(2)P/CoP achieves industrial-grade current densities(500 mA cm^(−2))at 1.75 V and 1.87 V in the overall urea electrolyzer(UOR||HER)and overall human urine electrolyzer(HUOR||HER),respectively,and demonstrates considerable durability.展开更多
The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on t...The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on the butt surface of Q235 steel via laser.The interaction behavior between the short fibers and the molten pool was captured using a high-speed camera.Laser-arc hybrid welding-brazing was then employed to join Al(6061-T6)to the steel.This process successfully created a short fiber-like interface structure at the joint.The relationship between microstructure and mechanical properties was investigated,compared with Al/bare steel(ABS)joint.The research results indicated that the IMCs layer consisted of FeAl_(3)and Fe_(2)Al_(5).The interface strength of the Al/short fiber-like surface structural steel(ASFSSS)joint reached 153.2 MPa,an 82.2%increase compared to the ABS joint,which reached 84.1 MPa.When the ASFSSS joints without the reinforcement were bent to 58.2°and 25.2°in the longitudinal and transverse direction,respectively,they remained intact.However,cracks were discovered when the bending angle of the ABS reached 39.1°and 0°in the two directions.Numerical simulation revealed that the short fiber-like interface structure significantly reduced residual stress and improved the stress distribution in the weld,thereby enhancing the strength and toughness of Al/steel dissimilar joints.The crack propagation path in the ASFSSS joint was deflected into the weld when it encountered short fibers,and the fracture morphology presented the characteristic of ductile-brittle mixed fracture.展开更多
The microstructure,micro-hardness,and tensile properties of interface between hot isostatic pressing densified low alloy steel and Inconel 690 cladding were investigated during the aging process at 600℃.The results s...The microstructure,micro-hardness,and tensile properties of interface between hot isostatic pressing densified low alloy steel and Inconel 690 cladding were investigated during the aging process at 600℃.The results show that the interface region can be divided into four zones from base metal to deposited metal:carbon-depleted zone(CDZ),partial melting zone(PMZ),planar growth zone(PGZ),and brownish feature zone(BFZ).Dimensions of these zones do not significantly change during aging.However,type I carbides noticeably increase in size in the PMZ,and precipitates clearly occur in the PGZ.The main reason for their growth and occurrence is continuous carbon migration.The highest micro-hardness appears in the PGZ and BFZ regions,which is related to carbon accumulation and precipitates in these regions.Tensile failure occurs on the base metal side due to the high strength mismatch between these two materials.The CDZ,composed of only ferrite,has lower strength and fractures at the boundary between CDZ and base metal.The ultimate tensile strength decreases by only 50 MPa after aging for 1500 h,and the interface region maintains high strength without significant deformation.展开更多
The formation of interphase layers,including the cathode-electrolyte interphase(CEI)and solidelectrolyte interphase(SEI),exhibits significant chemical complexity and plays a pivotal role in determining the performance...The formation of interphase layers,including the cathode-electrolyte interphase(CEI)and solidelectrolyte interphase(SEI),exhibits significant chemical complexity and plays a pivotal role in determining the performance of lithium batteries.Despite considerable advances in simulating the bulk phase properties of battery materials,the understanding of interfaces,including crystalline interfaces that represent the simplest case,remains limited.This is primarily due to challenges in performing ground-state searches for interface microstructures and the high computational costs associated with first-principles methods.Herein,we introduce InterOptimus,an automated workflow designed to efficiently search for ground-state heterogeneous interfaces.InterOptimus incorporates a rigorous,symmetry-aware equivalence analysis for lattice matching and termination scanning.Additionally,it introduces stereographic projection as an intuitive and comprehensive framework for visualizing and classifying interface structures.By integrating universal machine learning interatomic potentials(MLIPs),InterOptimus enables rapid predictions of interface energy and stability,significantly reducing the necessary computational cost in density functional theory(DFT)by over 90%.We benchmarked several MLIPs at three critical lithium battery interfaces,Li_(2)S|Ni_(3)S_(2),LiF|NCM,and Li_(3)PS_(4)|Li,and demonstrated that the MLIPs achieve accuracy comparable to DFT in modeling potential energy surfaces and ranking interface stabilities.Thus,InterOptimus facilitates the efficient determination of ground-state heterogeneous interface structures and subsequent studies of structure-property relationships,accelerating the interface engineering of novel battery materials.展开更多
Depression is increasingly prevalent among adolescents and can profoundly impact their lives.However,the early detection of depression is often hindered by the timeconsuming diagnostic process and the absence of objec...Depression is increasingly prevalent among adolescents and can profoundly impact their lives.However,the early detection of depression is often hindered by the timeconsuming diagnostic process and the absence of objective biomarkers.In this study,we propose a novel approach for depression detection based on an affective brain-computer interface(aBCI)and the resting-state electroencephalogram(EEG).By fusing EEG features associated with both emotional and resting states,our method captures comprehensive depression-related information.The final depression detection model,derived through decision fusion with multiple independent models,further enhances detection efficacy.Our experiments involved 40 adolescents with depression and 40 matched controls.The proposed model achieved an accuracy of 86.54%on cross-validation and 88.20%on the independent test set,demonstrating the efficiency of multi-modal fusion.In addition,further analysis revealed distinct brain activity patterns between the two groups across different modalities.These findings hold promise for new directions in depression detection and intervention.展开更多
Cleat serves as the primary flow pathway for coalbed methane(CBM)and water.However,few studies consider the impact of local contact on two-phase flow within cleats.A visual generalized model of endogenous cleats was c...Cleat serves as the primary flow pathway for coalbed methane(CBM)and water.However,few studies consider the impact of local contact on two-phase flow within cleats.A visual generalized model of endogenous cleats was constructed based on microfluidics.A microscopic and mesoscopic observation technique was proposed to simultaneously capture gas-liquid interface morphology of pores and throat and the two-phase flow characteristics in entire cleat system.The local contact characteristics of cleats reduced absolute permeability,which resulted in a sharp increase in the starting pressure.The reduced gas flow capacity narrowed the co-infiltration area and decreased water saturation at the isotonic point in a hydrophilic environment.The increased local contact area of cleats weakened gas phase flow capacity and narrowed the co-infiltration area.Jumping events occurred in methane-water flow due to altered porosity caused by local contact in cleats.The distribution of residual phases changed the jumping direction on the micro-scale as well as the dominant channel on the mesoscale.Besides,jumping events caused additional energy dissipation,which was ignored in traditional two-phase flow models.This might contribute to the overestimation of relative permeability.The work provides new methods and insights for investigating unsaturated flow in complex porous media.展开更多
Iron-based Prussian white(PW)materials have attracted considerable attention as promising cathodes for potassium-ion batteries(PIBs)due to their high capacity,easy preparation,and economic merits.However,the intrinsic...Iron-based Prussian white(PW)materials have attracted considerable attention as promising cathodes for potassium-ion batteries(PIBs)due to their high capacity,easy preparation,and economic merits.However,the intrinsic iron dissolution and uncontrollable cathode-electrolyte interface(CEI)formation in conventional organic electrolytes severely hinder their long-term cycling stability.Herein,we employ succinonitrile(SN),a bifunctional electrolyte additive,to suppress the iron dissolution and promote thin,uniform,and stable CEI formation of the PW cathode,thus improving its structural stability.Benefited from the coordination between the cyano groups in SN and iron atoms,this molecule can preferentially adsorb on the surface of PW to mitigate iron dissolution.SN also facilitates the decomposition of anions in potassium salt rather than organic solvents in electrolyte due to the attractive reaction between SN and anions.Consequently,the PW cathode with SN additive provides better electrochemical reversibility,showing capacity retention of 93.6%after 3000 cycles at 5C.In comparison,without SN,the capacity retention is only 87.4%after 1000 cycles under the same conditions.Moreover,the full cells of PW matched with commercial graphite(Gr)achieve stable cycling for 3500 cycles at a high rate of 20C,with an exceptional capacity decay of only 0.005%per cycle,surpassing the majority of recently reported results in literature.展开更多
The interface microstructures and strain distribution of dissimilar friction stir welding(FSW)of AA7075/AZ31B joints with or without ultrasonic vibration were examined.The results reveal that the ultrasonic vibrations...The interface microstructures and strain distribution of dissimilar friction stir welding(FSW)of AA7075/AZ31B joints with or without ultrasonic vibration were examined.The results reveal that the ultrasonic vibrations and tool offset greatly influence the dynamic recovery towards the Mg side by reducing the non-indexing region at the interface.Moreover,the grain recrystallization near the interface differed from the other areas due to severe deformation.Continuous dynamic recrystallization(CDRX)occurs at the AA7075 side,whereas the Mg side exhibits discontinuous dynamic recrystallization(DDRX).The higher net strain component was observed for ultrasonic-assisted FSW(UVaFSW).The strain component was changed significantly towards the AA7075 side compared with the AZ31B side.It occurred because of different recrystallization mechanisms.The strain component was well spread towards the AA7075 side,whereas the dispersed strain component was observed towards the AZ31B.Along the plate thickness direction,the intermetallic compound layer(IMC)thickness first increases,then decreases,reaching a maximum value of 1.5–1.8 mm from the top.The ultrasonic vibration reduced the overall thickness of intermetallic in the joint interface,regardless of the tool offset conditions.展开更多
Multimaterial digital light processing(DLP)three-dimensional(3D)printing technology provides unique advantages in the field of multi material additive manufacturing(MM AM)with its high resolution and rapid shaping cap...Multimaterial digital light processing(DLP)three-dimensional(3D)printing technology provides unique advantages in the field of multi material additive manufacturing(MM AM)with its high resolution and rapid shaping capabilities based on photopolymerization.However,owing to differences in the curing behavior and physical properties of different materials,multimaterial DLP 3D printing faces challenges such as insufficient interfacial bonding strength and unstable mechanical properties.In this study,two resins were integrated by multimaterial DLP 3D printing technology,and the effects of different layer thicknesses and exposure times on the interfacial bonding strength and morphology of the multimaterials were systematically investigated.The interfacial bonding mechanisms of the two resins was analyzed.It was found that increasing the exposure time can improve the interfacial bonding strength between materials,but certain limitations exist.A mathematical model relating the interfacial bonding strength to the exposure time and layer thickness was developed,and optimal process parameters were determined using optimization algorithms.A variable-parameter printing strategy for the interface was proposed to further improve the performance of printed parts.The maximum tensile strength of the multimaterial samples(44.43 MPa)using this strategy reached that of single-material parts(45 MPa),validating the feasibility of this strategy.This provides guidance for multimaterial DLP 3D printing processes and offers valuable insights for the future additive manufacturing of high-performance multimaterial components.展开更多
Lithium-sulfur(Li-S)battery is recognized for the high theoretical energy density and cost-effective raw materials.However,the instability of Li metal anodes limits the cycle life of Li-S batteries under practical con...Lithium-sulfur(Li-S)battery is recognized for the high theoretical energy density and cost-effective raw materials.However,the instability of Li metal anodes limits the cycle life of Li-S batteries under practical conditions.In this study,we propose a dual interface-passivating regulation strategy using nitrocellulose(NC),a macromolecular nitrate,to stabilize the interface/interphase between the electrolyte and Li metal anode.Specifically,the macromolecular crowding effect and the reduction in lithium polysulfides(LiPSs)activity through nitrate coordination endow NC desirable bifunctionality to simultaneously suppress the depletion of Li salts and LiPSs corrosion,leading to better interface passivation than mono-functional additives such as LiNO_(3)and carboxymethyl cellulose.Consequently,the cycle life of Li-S batteries under practically demanding conditions(50μm Li anodes;4.0 mg cm^(-2)S athodes)is extended to 180 cycles,outperforming those of additive-free or LiNO_(3)-containing commercial electrolytes.This study highlights the potential of bifunctional macromolecular additive design for effectively dual-passivating the anode/electrolyte interface towards highly stable practical Li-S batteries.展开更多
The stability of the“surrounding rock-backfill”com posite system is crucial for the safety of mining stopes.This study systematically investigates the effects of steel slag(SS)content and interface angle on the stre...The stability of the“surrounding rock-backfill”com posite system is crucial for the safety of mining stopes.This study systematically investigates the effects of steel slag(SS)content and interface angle on the strength and failure characteristics of rock and SS-cemented paste backfill composite specimens(RBCS)through uniaxial compression strength tests(UCS),acoustic emission systems(AE),and 3 D digital image correlation monitoring technology(3 D-DIC).The intrinsic mechanism by which SS content influences the strength of SS-CPB was revealed through an analysis of its hydration reaction degree and microstructural characteristics under varying SS content.Moreover,a theoretical strength model incorporating different interface angles was developed to explore the impact of interface inclination on failure modes and mechanical strength.The main conclusions are as follows:The incorporation of SS enhances the plastic characteristics of RBCS and reduces its brittleness,with the increase of SS content,the stress-strain curve of RBCS in the“staircase-like”stag e becomes smoother;When the interface angle is 45°,the RBCS stress-strain curve exhibits a bimodal feature,and the failure mode changes from Y-shaped fractures to interface and axial splitting;The addition of SS results in a reduction of hydration products such as Ca(OH)_(2) in the backfill cementing system and an increase in harmful pores,which weakens the bonding performance and strength of RBCS,and the SS content should not exceed 45%;As the interface angle increases,the strength of RBCS decreases,and the critical interface slip angle decreases first and then increases with the increase in the E S/E R ratio.This study provides technical references for the large-scale application of SS in mine backfill.展开更多
Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic lo...Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation.展开更多
Buried interface passivation is crucial for high-efficiency,stable perovskite solar cells(PSCs).Herein,we design a three-layer passivation structure toward the buried interface of inverted PSCs,consisting of NiO_(x),p...Buried interface passivation is crucial for high-efficiency,stable perovskite solar cells(PSCs).Herein,we design a three-layer passivation structure toward the buried interface of inverted PSCs,consisting of NiO_(x),poly(V-p-TPD)and PFN-Br(V-p-TPD,N,N'-di-p-tolyl-N,-N'-bis(4-vinylphenyl)-[1,1'-biphenyl]-4,4'-diamine;PFN-Br,poly[(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)]dibromide).Typically,in situ poly(V-p-TPD)layer on the NiO_(x) surface was obtained by a simple thermal crosslinking process.This poly(V-p-TPD)/NiO_(x) bilayer structure is beneficial for hole extraction and high-quality perovskite films with larger grain sizes and less lattice distortion.On this basis,the PFN-Br is further introduced as a surface modification layer,which can not only optimize the energy level alignment with the perovskite but also passivate defects and suppress carrier recombination at the perovskite bottom interface.Finally,inverted PSCs based on(FA_(0.95)Cs_(0.05))PbI_(3) present 25.5%efficiency with a low V_(OC)deficit.Besides,the devices could maintain 91.15%of the initial efficiency after being stored at 85℃for 1080 h,indicating excellent thermal stability.This work highlights the potential of a three-layered passivation structure based on crosslinking polymer HTLs for highly efficient and stable PSCs.展开更多
Photoelectrochemical(PEC)water splitting is an effective approach to directly convert solar energy into clean hydrogen fuel.As a visible-light-responsive p-type semiconductor,CuBi_(2)O_(4)possesses a suitable bandgap ...Photoelectrochemical(PEC)water splitting is an effective approach to directly convert solar energy into clean hydrogen fuel.As a visible-light-responsive p-type semiconductor,CuBi_(2)O_(4)possesses a suitable bandgap and good stability.However,its performance is inhibited by high interfacial resistance and severe charge carrier recombination.In this study,a CuO interlayer was introduced between fluorine-doped tin oxide(FTO)and CuBi_(2)O_(4)to construct CuO/CuBi_(2)O_(4)photocathodes,aiming to improve interfacial charge transfer.The results showed that CuO/CuBi_(2)O_(4)-200 exhibited a photocurrent density of−1.71 mA/cm^(2)at 0 V vs.RHE,which was more than 3.5 times higher than that of bare CuBi_(2)O_(4).The incident photon-to-current efficiency(IPCE)at 365 nm was enhanced to~13%and the maximum applied bias photon-to-current efficiency(ABPE)reached 0.17%.Water splitting experiments revealed a hydrogen yield of 2.05μmol/cm^(2),significantly surpassing that of the unmodified photoelectrode.The enhanced PEC performance indicated that the CuO layer established a favorable band alignment,promoted hole transport toward the FTO substrate and effectively suppressed interfacial carrier recombination.This work demonstrated a simple and efficient interfacial engineering strategy,offering new insights and guidance for the design and development of high-performance semiconductor-based PEC photoelectrodes.展开更多
基金supported by Guangdong Major Project of Basic and Applied Basic Research, China (No. 2020B0301030006)Fundamental Research Funds for the Central Universities, China (No. SWU-XDJH202313)+1 种基金Chongqing Postdoctoral Science Foundation Funded Project, China (No. 2112012728014435)the Chongqing Postgraduate Research and Innovation Project, China (No. CYS23197)。
文摘A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction.
基金supported by the National Natural Science Foundation of China(No.52472219,62133007)the project ZR2024ME073 supported by Shandong Provincial Natural Science Foundationthe Shenzhen Fundamental Research Program(No.JCYJ20220530141017039)。
文摘Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electrolyte system that employs a low-freezing-point diluent to compress solvation sheaths,enabling the formation of a compact anion-dominated solvation structure that enhances interfacial stability and safety.Molecular dynamics reveal the unique solvation structure with close packing of anions in this low-concentration electrolyte from the micro-mesoscopic scale.The optimized electrolyte combines cost-effectiveness,superior wettability,intrinsic nonflammability,and high stability,concurrently promoting a hybrid organic-inorganic solid electrolyte interphase(SEI)and cathode electrolyte interphase(CEI)for uniform lithium deposition.As a result,the Li‖LiFePO_(4)(LFP)full cells demonstrate stable cycling for 700 cycles at the current density of 4 C.Remarkably,the electrolyte demonstrates exceptional low-temperature performance,indicating broad operational viability.This work provides a promising electrolyte design strategy that addresses both safety and excellent electrochemical performance in high-energy-density metal-based batteries,including but not restricted to Li,Na,K and Zn multivalent ion systems.
基金the Key project of Nature Science Foundation of Tianjin(22JCZDJC00120)the 111 Project(B16027)for financial support.
文摘Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of fluorine atom influences the passivation effect and para-fluorinated one provided the most substantial performance enhancement mainly originating from ameliorated contact and energy band alignment between NiOx and perovskite,improved perovskite quality and defect healing.Resultantly,PSC with a power conversion efficiency of 24%can be achieved.Meanwhile,which can maintain 96.8%of the initial PCE after a 1000 h storage,presenting enhanced durability.This work highlights the critical role of molecular functionality and conformation in the buried interface modification of PSCs,providing valuable insights for future developments.
文摘Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inherent activity and incompatibility of the individual components themselves,and the irregular charge distribution and slow charge transfer ability between interfaces severely limit the activity of UOR.Therefore,we optimized and designed a Ni_(2)P/CoP interface with modulated surface charge distribution and directed charge transfer to promote UOR activity.Density functional theorycalculations first predict a regular charge transfer from CoP to Ni_(2)P,which creates a built-in electric field between Ni_(2)P and CoP interface.Optimization of the adsorption/desorption process of UOR/HER reaction intermediates leads to the improvement of catalytic activity.Electrochemical impedance spectroscopy and ex situ X-ray photoelectron spectroscopy characterization confirm the unique mechanism of facilitated reaction at the Ni_(2)P/CoP interface.Electrochemical tests further validated the prediction with excellent UOR/HER activities of 1.28 V and 19.7 mV vs.RHE,at 10 mA cm^(-2),respectively.Furthermore,Ni_(2)P/CoP achieves industrial-grade current densities(500 mA cm^(−2))at 1.75 V and 1.87 V in the overall urea electrolyzer(UOR||HER)and overall human urine electrolyzer(HUOR||HER),respectively,and demonstrates considerable durability.
基金supported by the National Natural Science Foundation of China(No.52275306)the Beijing Municipal Natural Science Foundation(No.3232021).
文摘The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on the butt surface of Q235 steel via laser.The interaction behavior between the short fibers and the molten pool was captured using a high-speed camera.Laser-arc hybrid welding-brazing was then employed to join Al(6061-T6)to the steel.This process successfully created a short fiber-like interface structure at the joint.The relationship between microstructure and mechanical properties was investigated,compared with Al/bare steel(ABS)joint.The research results indicated that the IMCs layer consisted of FeAl_(3)and Fe_(2)Al_(5).The interface strength of the Al/short fiber-like surface structural steel(ASFSSS)joint reached 153.2 MPa,an 82.2%increase compared to the ABS joint,which reached 84.1 MPa.When the ASFSSS joints without the reinforcement were bent to 58.2°and 25.2°in the longitudinal and transverse direction,respectively,they remained intact.However,cracks were discovered when the bending angle of the ABS reached 39.1°and 0°in the two directions.Numerical simulation revealed that the short fiber-like interface structure significantly reduced residual stress and improved the stress distribution in the weld,thereby enhancing the strength and toughness of Al/steel dissimilar joints.The crack propagation path in the ASFSSS joint was deflected into the weld when it encountered short fibers,and the fracture morphology presented the characteristic of ductile-brittle mixed fracture.
基金Major Scientific and Technological Project of Gansu(22ZD6GA008)Excellent Doctorate Project of Gansu(23JRRA806)National Natural Science Foundation of China(52175325,51961024,52071170)。
文摘The microstructure,micro-hardness,and tensile properties of interface between hot isostatic pressing densified low alloy steel and Inconel 690 cladding were investigated during the aging process at 600℃.The results show that the interface region can be divided into four zones from base metal to deposited metal:carbon-depleted zone(CDZ),partial melting zone(PMZ),planar growth zone(PGZ),and brownish feature zone(BFZ).Dimensions of these zones do not significantly change during aging.However,type I carbides noticeably increase in size in the PMZ,and precipitates clearly occur in the PGZ.The main reason for their growth and occurrence is continuous carbon migration.The highest micro-hardness appears in the PGZ and BFZ regions,which is related to carbon accumulation and precipitates in these regions.Tensile failure occurs on the base metal side due to the high strength mismatch between these two materials.The CDZ,composed of only ferrite,has lower strength and fractures at the boundary between CDZ and base metal.The ultimate tensile strength decreases by only 50 MPa after aging for 1500 h,and the interface region maintains high strength without significant deformation.
基金supported by the National Natural Science Foundation of China(92470110)the Special Funds for the Development of Strategic Emerging Industries in Shenzhen(XMHT20240108008)the Shenzhen Stable Support Program for Higher Education Institutions(WDZC20231126215806001)。
文摘The formation of interphase layers,including the cathode-electrolyte interphase(CEI)and solidelectrolyte interphase(SEI),exhibits significant chemical complexity and plays a pivotal role in determining the performance of lithium batteries.Despite considerable advances in simulating the bulk phase properties of battery materials,the understanding of interfaces,including crystalline interfaces that represent the simplest case,remains limited.This is primarily due to challenges in performing ground-state searches for interface microstructures and the high computational costs associated with first-principles methods.Herein,we introduce InterOptimus,an automated workflow designed to efficiently search for ground-state heterogeneous interfaces.InterOptimus incorporates a rigorous,symmetry-aware equivalence analysis for lattice matching and termination scanning.Additionally,it introduces stereographic projection as an intuitive and comprehensive framework for visualizing and classifying interface structures.By integrating universal machine learning interatomic potentials(MLIPs),InterOptimus enables rapid predictions of interface energy and stability,significantly reducing the necessary computational cost in density functional theory(DFT)by over 90%.We benchmarked several MLIPs at three critical lithium battery interfaces,Li_(2)S|Ni_(3)S_(2),LiF|NCM,and Li_(3)PS_(4)|Li,and demonstrated that the MLIPs achieve accuracy comparable to DFT in modeling potential energy surfaces and ranking interface stabilities.Thus,InterOptimus facilitates the efficient determination of ground-state heterogeneous interface structures and subsequent studies of structure-property relationships,accelerating the interface engineering of novel battery materials.
基金supported by the STI 2030 Major Projects(2022ZD0211700)the Key R&D Program of Guangdong Province,China(2018B030339001)+2 种基金the Key Realm R&D Program of Guangzhou,China(202007030007)the National Natural Science Foundation of China(82371538)The authors gratefully acknowledge the approval granted by the Ethics Committee of the Affiliated Brain Hospital of Guangzhou Medical University for this study involving human participants,with the approval ID(2021)No.071.
文摘Depression is increasingly prevalent among adolescents and can profoundly impact their lives.However,the early detection of depression is often hindered by the timeconsuming diagnostic process and the absence of objective biomarkers.In this study,we propose a novel approach for depression detection based on an affective brain-computer interface(aBCI)and the resting-state electroencephalogram(EEG).By fusing EEG features associated with both emotional and resting states,our method captures comprehensive depression-related information.The final depression detection model,derived through decision fusion with multiple independent models,further enhances detection efficacy.Our experiments involved 40 adolescents with depression and 40 matched controls.The proposed model achieved an accuracy of 86.54%on cross-validation and 88.20%on the independent test set,demonstrating the efficiency of multi-modal fusion.In addition,further analysis revealed distinct brain activity patterns between the two groups across different modalities.These findings hold promise for new directions in depression detection and intervention.
基金the financial support from the National Natural Science Foundation of China (No.42102127)the Postdoctoral Research Foundation of China (No.2024 M751860)。
文摘Cleat serves as the primary flow pathway for coalbed methane(CBM)and water.However,few studies consider the impact of local contact on two-phase flow within cleats.A visual generalized model of endogenous cleats was constructed based on microfluidics.A microscopic and mesoscopic observation technique was proposed to simultaneously capture gas-liquid interface morphology of pores and throat and the two-phase flow characteristics in entire cleat system.The local contact characteristics of cleats reduced absolute permeability,which resulted in a sharp increase in the starting pressure.The reduced gas flow capacity narrowed the co-infiltration area and decreased water saturation at the isotonic point in a hydrophilic environment.The increased local contact area of cleats weakened gas phase flow capacity and narrowed the co-infiltration area.Jumping events occurred in methane-water flow due to altered porosity caused by local contact in cleats.The distribution of residual phases changed the jumping direction on the micro-scale as well as the dominant channel on the mesoscale.Besides,jumping events caused additional energy dissipation,which was ignored in traditional two-phase flow models.This might contribute to the overestimation of relative permeability.The work provides new methods and insights for investigating unsaturated flow in complex porous media.
基金funding support from the Macao Science and Technology Development Fund(0013/2021/AMJ and 0082/2022/A2)support from the Multi-Year Research Grants(MYRG2022-00266-IAPME,and MYRG-GRG2023-00224-IAPME)provided by the Research&Development Office at the University of Macao+2 种基金the National Natural Science Foundation of China(52202328)the Shanghai Sailing Program(22YF1455500)the Shanghai Magnolia Talent Plan Pujiang Project(24PJD128)for their financial support。
文摘Iron-based Prussian white(PW)materials have attracted considerable attention as promising cathodes for potassium-ion batteries(PIBs)due to their high capacity,easy preparation,and economic merits.However,the intrinsic iron dissolution and uncontrollable cathode-electrolyte interface(CEI)formation in conventional organic electrolytes severely hinder their long-term cycling stability.Herein,we employ succinonitrile(SN),a bifunctional electrolyte additive,to suppress the iron dissolution and promote thin,uniform,and stable CEI formation of the PW cathode,thus improving its structural stability.Benefited from the coordination between the cyano groups in SN and iron atoms,this molecule can preferentially adsorb on the surface of PW to mitigate iron dissolution.SN also facilitates the decomposition of anions in potassium salt rather than organic solvents in electrolyte due to the attractive reaction between SN and anions.Consequently,the PW cathode with SN additive provides better electrochemical reversibility,showing capacity retention of 93.6%after 3000 cycles at 5C.In comparison,without SN,the capacity retention is only 87.4%after 1000 cycles under the same conditions.Moreover,the full cells of PW matched with commercial graphite(Gr)achieve stable cycling for 3500 cycles at a high rate of 20C,with an exceptional capacity decay of only 0.005%per cycle,surpassing the majority of recently reported results in literature.
基金supported by postdoctoral program of Shandong University,Jinan,Chinathe financial support from the National Natural Science Foundation of China(Grant Nos.52035005)the Key R&D Program of Shandong Province in China(Grant No.2021ZLGX01)。
文摘The interface microstructures and strain distribution of dissimilar friction stir welding(FSW)of AA7075/AZ31B joints with or without ultrasonic vibration were examined.The results reveal that the ultrasonic vibrations and tool offset greatly influence the dynamic recovery towards the Mg side by reducing the non-indexing region at the interface.Moreover,the grain recrystallization near the interface differed from the other areas due to severe deformation.Continuous dynamic recrystallization(CDRX)occurs at the AA7075 side,whereas the Mg side exhibits discontinuous dynamic recrystallization(DDRX).The higher net strain component was observed for ultrasonic-assisted FSW(UVaFSW).The strain component was changed significantly towards the AA7075 side compared with the AZ31B side.It occurred because of different recrystallization mechanisms.The strain component was well spread towards the AA7075 side,whereas the dispersed strain component was observed towards the AZ31B.Along the plate thickness direction,the intermetallic compound layer(IMC)thickness first increases,then decreases,reaching a maximum value of 1.5–1.8 mm from the top.The ultrasonic vibration reduced the overall thickness of intermetallic in the joint interface,regardless of the tool offset conditions.
基金supported by National Key R&D Program of China(Grant No.2022YFB4600103)National Youth Talent Support Program,China Postdoctoral Science Foundation(Grant No.2021M692555)+1 种基金Shaanxi Province Qinchuangyuan'Scientists+Engineers'Team Building Project(Grant No.2023KXJ-266)Fundamental Research Funds for the Central Universities(Grant No.xzy012023145)。
文摘Multimaterial digital light processing(DLP)three-dimensional(3D)printing technology provides unique advantages in the field of multi material additive manufacturing(MM AM)with its high resolution and rapid shaping capabilities based on photopolymerization.However,owing to differences in the curing behavior and physical properties of different materials,multimaterial DLP 3D printing faces challenges such as insufficient interfacial bonding strength and unstable mechanical properties.In this study,two resins were integrated by multimaterial DLP 3D printing technology,and the effects of different layer thicknesses and exposure times on the interfacial bonding strength and morphology of the multimaterials were systematically investigated.The interfacial bonding mechanisms of the two resins was analyzed.It was found that increasing the exposure time can improve the interfacial bonding strength between materials,but certain limitations exist.A mathematical model relating the interfacial bonding strength to the exposure time and layer thickness was developed,and optimal process parameters were determined using optimization algorithms.A variable-parameter printing strategy for the interface was proposed to further improve the performance of printed parts.The maximum tensile strength of the multimaterial samples(44.43 MPa)using this strategy reached that of single-material parts(45 MPa),validating the feasibility of this strategy.This provides guidance for multimaterial DLP 3D printing processes and offers valuable insights for the future additive manufacturing of high-performance multimaterial components.
基金supported by the National Natural Science Foundation of China(22379021 and 22479021)。
文摘Lithium-sulfur(Li-S)battery is recognized for the high theoretical energy density and cost-effective raw materials.However,the instability of Li metal anodes limits the cycle life of Li-S batteries under practical conditions.In this study,we propose a dual interface-passivating regulation strategy using nitrocellulose(NC),a macromolecular nitrate,to stabilize the interface/interphase between the electrolyte and Li metal anode.Specifically,the macromolecular crowding effect and the reduction in lithium polysulfides(LiPSs)activity through nitrate coordination endow NC desirable bifunctionality to simultaneously suppress the depletion of Li salts and LiPSs corrosion,leading to better interface passivation than mono-functional additives such as LiNO_(3)and carboxymethyl cellulose.Consequently,the cycle life of Li-S batteries under practically demanding conditions(50μm Li anodes;4.0 mg cm^(-2)S athodes)is extended to 180 cycles,outperforming those of additive-free or LiNO_(3)-containing commercial electrolytes.This study highlights the potential of bifunctional macromolecular additive design for effectively dual-passivating the anode/electrolyte interface towards highly stable practical Li-S batteries.
基金Project(52308316)supported by the National Natural Science Foundation of China,Project(BBJ2024088)supported by the Fundamental Research Funds for the Central Universities(PhD.Top Innovative Talents Fund of CUMTB),China。
文摘The stability of the“surrounding rock-backfill”com posite system is crucial for the safety of mining stopes.This study systematically investigates the effects of steel slag(SS)content and interface angle on the strength and failure characteristics of rock and SS-cemented paste backfill composite specimens(RBCS)through uniaxial compression strength tests(UCS),acoustic emission systems(AE),and 3 D digital image correlation monitoring technology(3 D-DIC).The intrinsic mechanism by which SS content influences the strength of SS-CPB was revealed through an analysis of its hydration reaction degree and microstructural characteristics under varying SS content.Moreover,a theoretical strength model incorporating different interface angles was developed to explore the impact of interface inclination on failure modes and mechanical strength.The main conclusions are as follows:The incorporation of SS enhances the plastic characteristics of RBCS and reduces its brittleness,with the increase of SS content,the stress-strain curve of RBCS in the“staircase-like”stag e becomes smoother;When the interface angle is 45°,the RBCS stress-strain curve exhibits a bimodal feature,and the failure mode changes from Y-shaped fractures to interface and axial splitting;The addition of SS results in a reduction of hydration products such as Ca(OH)_(2) in the backfill cementing system and an increase in harmful pores,which weakens the bonding performance and strength of RBCS,and the SS content should not exceed 45%;As the interface angle increases,the strength of RBCS decreases,and the critical interface slip angle decreases first and then increases with the increase in the E S/E R ratio.This study provides technical references for the large-scale application of SS in mine backfill.
基金financially supported by the National Natural Science Foundation of China(52472248 and 22075221)the Key Research and Development Project of Shanxi Province(202202060301003 and 202202060301015)the Innovation Program of Wuhan-Shuguang Project(2023010201020367)。
文摘Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation.
基金financial support from the Ministry of Science and Technology of China(2021YFB3800103)Natural Science Foundation of China(U24A6003,52361145847,52172260,52227803,52222212)Chinese Academy of Sciences-Commonwealth Scientific and Industrial Research Organization(CAS-CSIRO)Joint Project(112111KYSB20210017)。
文摘Buried interface passivation is crucial for high-efficiency,stable perovskite solar cells(PSCs).Herein,we design a three-layer passivation structure toward the buried interface of inverted PSCs,consisting of NiO_(x),poly(V-p-TPD)and PFN-Br(V-p-TPD,N,N'-di-p-tolyl-N,-N'-bis(4-vinylphenyl)-[1,1'-biphenyl]-4,4'-diamine;PFN-Br,poly[(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)]dibromide).Typically,in situ poly(V-p-TPD)layer on the NiO_(x) surface was obtained by a simple thermal crosslinking process.This poly(V-p-TPD)/NiO_(x) bilayer structure is beneficial for hole extraction and high-quality perovskite films with larger grain sizes and less lattice distortion.On this basis,the PFN-Br is further introduced as a surface modification layer,which can not only optimize the energy level alignment with the perovskite but also passivate defects and suppress carrier recombination at the perovskite bottom interface.Finally,inverted PSCs based on(FA_(0.95)Cs_(0.05))PbI_(3) present 25.5%efficiency with a low V_(OC)deficit.Besides,the devices could maintain 91.15%of the initial efficiency after being stored at 85℃for 1080 h,indicating excellent thermal stability.This work highlights the potential of a three-layered passivation structure based on crosslinking polymer HTLs for highly efficient and stable PSCs.
基金Supported by Educational Department(JYTMS20230310)Natural Science Foundation of Liaoning Province(2024-MS-215)。
文摘Photoelectrochemical(PEC)water splitting is an effective approach to directly convert solar energy into clean hydrogen fuel.As a visible-light-responsive p-type semiconductor,CuBi_(2)O_(4)possesses a suitable bandgap and good stability.However,its performance is inhibited by high interfacial resistance and severe charge carrier recombination.In this study,a CuO interlayer was introduced between fluorine-doped tin oxide(FTO)and CuBi_(2)O_(4)to construct CuO/CuBi_(2)O_(4)photocathodes,aiming to improve interfacial charge transfer.The results showed that CuO/CuBi_(2)O_(4)-200 exhibited a photocurrent density of−1.71 mA/cm^(2)at 0 V vs.RHE,which was more than 3.5 times higher than that of bare CuBi_(2)O_(4).The incident photon-to-current efficiency(IPCE)at 365 nm was enhanced to~13%and the maximum applied bias photon-to-current efficiency(ABPE)reached 0.17%.Water splitting experiments revealed a hydrogen yield of 2.05μmol/cm^(2),significantly surpassing that of the unmodified photoelectrode.The enhanced PEC performance indicated that the CuO layer established a favorable band alignment,promoted hole transport toward the FTO substrate and effectively suppressed interfacial carrier recombination.This work demonstrated a simple and efficient interfacial engineering strategy,offering new insights and guidance for the design and development of high-performance semiconductor-based PEC photoelectrodes.
