This study demonstrates the successful fabrication of solid-state bilayers using LiFePO_(4)(LFP)cathodes and Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-based Composite Solid Electrolytes(CSEs)via Cold Sintering Proces...This study demonstrates the successful fabrication of solid-state bilayers using LiFePO_(4)(LFP)cathodes and Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-based Composite Solid Electrolytes(CSEs)via Cold Sintering Process(CSP).By optimizing the sintering pressure,it is achieved an intimate contact between the cathode and the solid electrolyte,leading to an enhanced electrochemical performance.Bilayers cold sintered at 300 MPa and a low-sintering temperature of 150℃exhibit high ionic conductivities(0.5 mS cm^(-1))and stable specific capacities at room temperature(160.1 mAh g^(-1)LFP at C/10 and 75.8 mAh g^(-1)_(LFP)at 1 C).Moreover,an operando electrochemical impedance spectroscopy(EIS)technique is employed to identify limiting factors of the bilayer kinetics and to anticipate the overall electrochemical behavior.Results suggest that capacity fading can occur in samples prepared with high sintering pressures due to a volume reduction in the LFP crystalline cell.This work demonstrates the potential of CSP to produce straightforward high-performance bilayers and introduces a valuable non-destructive instrument for understanding and avoiding degradation in solid-state lithium-based batteries.展开更多
Inadequate interfacial contact between lithium and solid-state electrolytes(SSEs)leads to elevated impedance and the growth of lithium dendrites,presenting significant obstacles to the practical viability of solid-sta...Inadequate interfacial contact between lithium and solid-state electrolytes(SSEs)leads to elevated impedance and the growth of lithium dendrites,presenting significant obstacles to the practical viability of solid-state batteries(SSBs).To ameliorate interfacial contact,optimizing the surface treatment of SSEs has been widely adopted.However,the formation of LiCl through acid treatment,an equally crucial factor impacting SSB performance,has received limited attention,leaving its underlying mechanism unclear.Our study aims to shed light on SSE characteristics following LiCl formation and the removal of Li_(2)CO_(3) through acid treatment.We seek to establish quantifiable links between SSE surface structure and SSB performance,focusing on interfacial resistance,current distribution,critical current density(CCD),and lithium deposition.The formation of LiCl,occurring as Li_(2)CO_(3) is removed through acid treatment,effectively mitigates lithium dendrite formation on SSE surfaces.This action inhibits electron injection and reduces the diffusion rate of Li atoms.Simultaneously,acid treatment transforms the SSE surface into a lithiophilic state by eliminating surface Li_(2)CO_(3).Consequently,the interfacial resistance between lithium and SSEs substantially decreases from 487.67 to 35.99Ωcm^(2) at 25°C.This leads to a notably high CCD of 1.3 mA cm^(-2) and a significantly extended cycle life of 1,000 h.Furthermore,in full SSBs incorporating LiCoO_(2)cathodes and acid-treated garnet SSEs,we observe exceptional cyclability and rate capability.Our findings highlight that acid treatment not only establishes a fundamental relationship between SSE surfaces and battery performance but also offers an effective strategy for addressing interfacial challenges in SSBs.展开更多
Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of...Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on FEC.Unprecedented stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only additive.DAMS-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs.展开更多
Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power densi...Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power density.However,issues,such as the corrosion and dissolution of the Zn anode,limited wet-tability,and lack of sufficient nucleation sites for Zn plating,have limited their practical application.The introduction of a protective layer comprising of tellurium(Te)nanobelts onto the surface of Zn anode has emerged as a promising approach to overcome these limitations and improve the electrochemical behav-ior by enhancing the safety and wettability of ZIBs,as well as providing numerous nucleation sites for Zn plating.In the presence of a Te-based protective layer,the energy power density of the surface-engineered Zn anode improved significantly(ranging from 310 to 144 W h kg^(-1),over a power density range of 270 to 1,800 W kg^(-1)),and the lifespan capability was extended.These results demonstrate that the proposed strategy of employing Te nanobelts as a protective layer holds great promise for enhancing the energy storage performance of zIBs,making them even more attractive as a viable energy storage solution forthefuture.展开更多
Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(...Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(3)materials is still low due to the evaporation energy of Se(37.70 kJ mol^(-1))being much lower than that of Te(52.55 kJ mol^(-1)).The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency.Here,we have developed a new approach for the high-performance and stable n-type Se-free Bi_(2)Te_(3)-based materials bymaximizing the electronic transport while suppressing the phonon transport,at the same time.Spontaneously generated FeTe_(2)nanoinclusions within the matrix during the melt-spinning and subsequent spark plasma sintering is the key to simultaneous engineering of the power factor and lattice thermal conductivity.The nanoinclusions change the fermi level of the matrix while intensifying the phonon scattering via nanoparticles.With a fine-tuning of the fermi level with Cu doping in the n-type Bi_(2)Te_(3)-0.02FeTe_(2),a high power factor of∼41×10^(-4)Wm^(-1)K^(-2)with an average zT of 1.01 at the temperature range 300-470 K are achieved,which are comparable to those obtained in n-type Bi_(2)(Te,Se)_(3)materials.The proposed approach enables the fabrication of high-performance n-type Bi_(2)Te_(3)-based materials without having to include volatile Se element,which guarantees the stability of the material.Consequently,widespread application of thermoelectric devices utilizing the n-type Bi_(2)Te_(3)-based materials will become possible.展开更多
The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,...The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,leading to the destruction of the coating layers.Investigating how carbon content affects element diffusion in silicon carbide-based TRISO composite fuel is of great significance for predicting reactor safety.In this study,silicon carbide-based TRISO composite fuels with different carbon contents were prepared by adding varying amounts of phenolic resin to the silicon carbide matrix.X-ray Diffraction(XRD)and Scanning Electron Microscopy(SEM)were employed to characterize the phase composition,morphology,and microstructure of the composite fuels.The elemental content in each coating layer of TRISO was quantified using Energy-Dispersive X-ray Spectroscopy(EDS).The results demonstrated that the addition of phenolic resin promoted the uniform distribution of sintering aids in the silicon carbide matrix.The atomic percentage(at.%)of aluminum(Al)in the pyrolytic carbon layer of the TRISO particles reached its lowest value of 0.55%when the phenolic resin addition was 1%.This is because the addition of phenolic resin caused the Al and silicon(Si)in the matrix to preferentially react with the carbon in the phenolic resin to form a metastable liquid phase,rather than preferentially consuming the pyrolytic carbon in the outer coating layer of the TRISO particles.The findings suggest that carbon addition through phenolic resin incorporation can effectively mitigate the deleterious reactions between the TRISO coating layers and sintering aids,thereby enhancing the durability and safety of silicon carbide-based TRISO composite fuels.展开更多
All-solid-state batteries(ASSBs)are pursued due to their potential for better safety and high energy density.However,the energy density of the cathode for ASSBs does not seem to be satisfactory due to the low utilizat...All-solid-state batteries(ASSBs)are pursued due to their potential for better safety and high energy density.However,the energy density of the cathode for ASSBs does not seem to be satisfactory due to the low utilization of active materials(AMs)at high loading.With small amount of solid electrolyte(SE)powder in the cathode,poor electrochemical performance is often observed due to contact loss and non-homogeneous distribution of AMs and SEs,leading to high tortuosity and limitation of lithium and electron transport pathways.Here,we propose a novel cathode design that can achieve high volumetric energy density of 1258 Wh L^(-1)at high AM content of 85 wt%by synergizing the merits of AM@SE core–shell composite particles with conformally coated thin SE shell prepared from mechanofusion process and small SE particles.The core–shell structure with an intimate and thin SE shell guarantees high ionic conduction pathway while unharming the electronic conduction.In addition,small SE particles play the role of a filler that reduces the packing porosity in the cathode composite electrode as well as between the cathode and the SE separator layer.The systematic demonstration of the optimization process may provide understanding and guidance on the design of electrodes for ASSBs with high electrode density,capacity,and ultimately energy density.展开更多
Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and...Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and unstable surface electrochemistry.This study introduces a practical method for scattering untreated bulk hexagonal boron nitride(h-BN)particles onto the zinc anode surface.During cycling,stabilized zinc fills the interstices of scattered h-BN,resulting in a more favorable(002)orientation.Consequently,zinc dendrite formation is effectively suppressed,leading to improved electrochemical stability.The zinc with scattered h-BN in a symmetric cell configuration maintains stability 10 times longer than the bare zinc symmetric cell,lasting 500 hours.Furthermore,in a full cell configuration withα-MnO_(2) cathode,increased H^(+)ion activity can effectively alter the major redox kinetics of cycling due to the presence of scattered h-BN on the zinc anode.This shift in H^(+)ion activity lowers the overall redox potential,resulting in a discharge capacity retention of 96.1%for 300 cycles at a charge/discharge rate of 0.5 Ag^(-1).This study highlights the crucial role of surface modification,and the innovative use of bulk h-BN provides a practical and effective solution for improving the performance and stability.展开更多
Cerium was extracted from rare earth slurry waste used for polishing a glass substrate.Initially,glass frit and flocculant were removed by froth flotation and dissolution.The recovered rare earth slurry exhibited almo...Cerium was extracted from rare earth slurry waste used for polishing a glass substrate.Initially,glass frit and flocculant were removed by froth flotation and dissolution.The recovered rare earth slurry exhibited almost the same particle size distribution as original slurry,which could be reused as slurry for glass polishing.From the rare earth slurry,the cerium solution was obtained by an oxidative thermal treatment and subsequent chemical leaching.The cerium solution was further purified up to 94% by selective precipitation of rare earth species.展开更多
AIM To investigate histologic abnormalities in the gastric smooth muscle of patients with diabetes mellitus(DM).METHODS Full-thickness gastric specimens were obtained from patients undergoing surgery for gastric cance...AIM To investigate histologic abnormalities in the gastric smooth muscle of patients with diabetes mellitus(DM).METHODS Full-thickness gastric specimens were obtained from patients undergoing surgery for gastric cancer. H&E stain and Masson's Trichrome stain were performed to assess the degree of fibrosis. Immunohistochemical staining using various antibodies was also performed [antibodies against protein gene product 9.5(PGP9.5), neuronal nitric oxide synthase(n NOS), vasoactive intestinal peptide(VIP), neurokinin-1(NK1) receptor, c-Kit, and platelet-derived growth factor receptor-alpha,(PDGFRα)]. Immunofluorescent staining and evaluation with confocal microscopy were also conducted.RESULTS Twenty-six controls and 35 diabetic patients(21 shortduration patients and 14 long-duration patients) were included. There were no significant differences in basic demographics between the two groups except in mean body mass index(BMI)(higher in the DM group). Proportions of moderate-to-severe intercellular fibrosis in the muscle layer were significantly higher in the DM group than in the control group(P < 0.01). On immunohistochemical staining, c-Kit- and PDGFRα-positive immunoreactivity were significantly decreased in the DM group compared with the control group(P < 0.05). There were no statistically significant differences in PGP9.5, n NOS, VIP, and neurokinin 1 expression. On immunofluorescent staining, cellularity of interstitial cells of Cajal(ICC) was observed to decrease with increasing duration of DM.CONCLUSION Our study suggests that increased intercellular fibrosis, loss of ICC, and loss of fibroblast-like cells are found in the smooth muscle of DM patients. These abnormalities may contribute to changes in gastric motor activity in patients with DM.展开更多
Approaches for the fabrication of a low power-operable formaldehyde(HCHO)gas sensor with high sensitivity and selectivity were performed by the utilization of an effective micro-structured platform with a micro-heater...Approaches for the fabrication of a low power-operable formaldehyde(HCHO)gas sensor with high sensitivity and selectivity were performed by the utilization of an effective micro-structured platform with a micro-heater to reach high temperature with low heating power as well as by the integration of indium oxide(In2O3)nanofibers decorated with well-dispersed Au nanoparticles as a sensing material.Homogeneous In2O3 nanofibers with the large specific surface area were prepared by the electrospinning following by calcination process.Au nanoparticles with the well-controlled size as a catalyst were synthesized on the surface of In2O3 nanofibers.The Au-decorated In2O3 nanofibers were reliably integrated as sensing materials on the bridge-type micro-platform including micro-heaters and micro-electrodes.The micro-platform designed to maintain high temperature with low power consumption was fabricated by a microelectromechanical system(MEMS)technique.The micro-platform gas sensor consisting with Au-In2O3 nanofibers were fabricated effectively to detect HCHO gases with high sensitivity and selectivity.The HCHO gas sensing behaviors were schematically studied as a function of the gas concentration,the size of the adsorbed Au nanoparticles,the applied power to raise the temperature of a sensing part and the kind of target gases.展开更多
Barium titanate (BaTiO3) and silver (Ag) composite film with high dielectric constant was grown at room temperature by an aerosol deposition method.The dielectric constant increases by 0.5 times after adding Ag to the...Barium titanate (BaTiO3) and silver (Ag) composite film with high dielectric constant was grown at room temperature by an aerosol deposition method.The dielectric constant increases by 0.5 times after adding Ag to the BaTiO3 matrix,compared with pure BaTiO3.The high dielectric constant can be attributed to the percolation effect of Ag inclusions in the BaTiO3 matrix.The Ag was present in the form of discrete layer in the BaTiO3 film.The dielectric properties of BaTiO3 Ag were discussed in detail taking into account the changes in microstructures.展开更多
In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/D) process. And, unlike the conventional R/D process, calcium reduction that is a crucial step for the formati...In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/D) process. And, unlike the conventional R/D process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with Ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 ℃. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was <<1 μm. Most Nd2Fe14B particles were enclosed with thin layers of Nd-rich phase. Typical magnetic properties of such powder without eliminating impurity CaO were iHc=～5.9 kOe, Br=～5.5 kG, and (BH)max=～6 MGOe.展开更多
The single-pot production of Pd@Pt core-shell structures is a promising approach as it offers large surface area,catalytic capability,and stability.In this work,we established a single-pot process to produce Pd@Pt cor...The single-pot production of Pd@Pt core-shell structures is a promising approach as it offers large surface area,catalytic capability,and stability.In this work,we established a single-pot process to produce Pd@Pt core-shell nanodendrites with tunable composition,shape and size for optimal electrochemical activity.Pd@Pt nanodendrites with diverse compositions were synthesized by tuning the ratios of Pd and Pt sources in an aqueous environment using cetyltrimethylammonium chloride,which functioned as both the surfactant and the reducing agent at an elevated temperature(90°C).The synthesized Pd5@Pt5 nanodendrites showed exceptional electrochemical action toward the methanol oxidation reaction related with another compositional Pd@Pt nanodendrites and conventional Pt/C electrocatalysts.In addition,Pd5@Pt5 nanodendrites exhibited good CO tolerance owing to their surface features and the synergistic effect among Pt and Pd.Meanwhile,nanodendrites with a Pt-rich surface provided exceptional catalytic active sites.Compared with the conventional Pt/C electrocatalyst,the anodic peak current obtained by Pd5@Pt5 nanodendrites was 3.74 and 2.18 times higher in relations of mass and electrochemical active surface area-normalized current density,respectively.This approach offers an attractive strategy to design electrocatalysts with unique structures and outstanding catalytic performance and stability for electrochemical energy conversion.展开更多
An approach named ＂pore structure collapsed replication route＂ has been developed to prepare mesoporous WC materials with a high surface area （105 m2/g） and crystallized framework at a temperature as low as 700 ℃...An approach named ＂pore structure collapsed replication route＂ has been developed to prepare mesoporous WC materials with a high surface area （105 m2/g） and crystallized framework at a temperature as low as 700 ℃. The XRD, TEM, EDS, and BET characterizations were conducted to analyze the effects of the synthesis parameters and the template types on the structure of mesoporous WC. The compaction on the templates is the key to form mesoporous structure of WC while the templates help to control the size of crystalline. At a content of 7 wt% for the precursor of WC, the mesoporous WC could be formed with well ordered structure.展开更多
In order to provide the kinetic mechanism for optimizing the quality of the hydroxyapatite （Ca 10（PO4）6-（OH）2, HA） coating on Ti-alloy orthopedic devices, the high temperature behavior of HA-titania （TiO2） com...In order to provide the kinetic mechanism for optimizing the quality of the hydroxyapatite （Ca 10（PO4）6-（OH）2, HA） coating on Ti-alloy orthopedic devices, the high temperature behavior of HA-titania （TiO2） composite specimen was investigated using XRD, FTIR and 31P MAS NMR methods. Thermal treatment of HA-TiO2 mixture powders leads to dehydroxylate and decompound of HA as well as chemical reaction between the two materials. Evidence for the initiation of the dehydroxylation of hydroxyapatite was found at 700℃ in air. The decomposition product of β-tricalcium phosphate was proven at 900℃ in air. Additionally, the formation of CaTiO3, derived from the chemical reaction between HA and titania at 900℃, was confirmed.展开更多
New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of ...New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of impingement tests and are evaluated according to their cold crushing strengths at room temperature. The combination of carbon nanotubes and alumina nanosheets additives leads to in situ formation of Al3 CON. Both the nanoscaled additives as well as the extra alumina “active”coating lead to improved mechanical performance of the carbon bonded filters and open the horizon for filter macrostructures with higher filtration capacities in means of bigger dimensions. In a further step MWCNT（ multi walled carbon nanotubes） in combination with a synthetic pitch have been used as a functional coating on the surface of alumina carbon bonded filters. These filters have then been evaluated also with uncoated filters in a special casting simulator and the interactions between steel and filtering material have been investigated.展开更多
The corrosion of refractory crucibles by a highly cor- rosive steel （18CrNiMo7-6） with a high aluminum con- tent and casting temperature of 1 580℃ was investiga- ted. The tested refractories were alumina, muUite an...The corrosion of refractory crucibles by a highly cor- rosive steel （18CrNiMo7-6） with a high aluminum con- tent and casting temperature of 1 580℃ was investiga- ted. The tested refractories were alumina, muUite and alumina doped with zirconia and titania （ AZT）. The samples were decreasingly attacked in the sequence AZT, alumina and mullite with corrosion layers of about 14, 6 and 1 mm, respectively. In the alumina and AZT, compositions corresponding to manganese aluminates and subsequently manganese aluminosilicates formed with manganese and silicon from the steel. In the mullite cru- cible, compositions corresponding to manganese aluminosilicates formed directly with manganese from the steel giving a highly viscous interfacial melt which retarded the further corrosion.展开更多
The development of electrolytes with high ionic conductivity and stable electrode–electrolyte interfaces is crucial for the practical realization of solid-state sodium batteries.In this study,the effect of heteroatom...The development of electrolytes with high ionic conductivity and stable electrode–electrolyte interfaces is crucial for the practical realization of solid-state sodium batteries.In this study,the effect of heteroatom doping in a von-Alpen-type Na super ionic conductor(NASICON)was investigated by substituting Zr^(4+)with Mg^(2+),Zn^(2+),and La^(3+)to enhance its material properties and evaluate its potential for solid-state sodium battery applications.Computational chemistry was employed to predict the thermodynamic stability influenced by dopant introduction and the changes in ionic conductivity arising from crystal structure distortion,with the predictions validated by experiments.The optimized Zn^(2+)-doped NASICON(Zn-NZSP0.07)exhibited the highest total ionic conductivity of 2.74×10^(−3)S∙cm^(−1),representing a 4.5-fold increase compared with undoped NASICON(6.00×10−4 S∙cm^(−1)).The material also showed a high relative density of 99.1%,indicating a compact and well-sintered microstructure,as confirmed by a three-point bending test.Furthermore,a high critical current density of 1.4 mA∙cm^(−2)was achieved in symmetric cell testing.Additionally,a Na_(3)V_(2)(PO_(4))_(3)||Zn-NZSP0.07||Na cell delivered an initial capacity of 103.9 mAh∙g^(−1)at 0.1 A∙g^(−1)and retained 73.4%of its capacity after 200 cycles.These results demonstrate that optimal heteroatom doping is crucial for enhancing the performance of NASICON.展开更多
基金support from Generalitat Valenciana under Pla Complementari“Programa de Materials Avanc¸ats”,2022(grant number MFA/2022/030)Ministerio de Ciencia,Innovaci´on y Universidades(Spain)(grant number MCIN/AEI/10.13039/501100011033)+1 种基金support from UJI(UJI-2023-16 and GACUJIMC/2023/08)Generalitat Valenciana through FPI Fellowship Program(grant numbers ACIF/2020/294 and CIACIF/2021/050).
文摘This study demonstrates the successful fabrication of solid-state bilayers using LiFePO_(4)(LFP)cathodes and Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-based Composite Solid Electrolytes(CSEs)via Cold Sintering Process(CSP).By optimizing the sintering pressure,it is achieved an intimate contact between the cathode and the solid electrolyte,leading to an enhanced electrochemical performance.Bilayers cold sintered at 300 MPa and a low-sintering temperature of 150℃exhibit high ionic conductivities(0.5 mS cm^(-1))and stable specific capacities at room temperature(160.1 mAh g^(-1)LFP at C/10 and 75.8 mAh g^(-1)_(LFP)at 1 C).Moreover,an operando electrochemical impedance spectroscopy(EIS)technique is employed to identify limiting factors of the bilayer kinetics and to anticipate the overall electrochemical behavior.Results suggest that capacity fading can occur in samples prepared with high sintering pressures due to a volume reduction in the LFP crystalline cell.This work demonstrates the potential of CSP to produce straightforward high-performance bilayers and introduces a valuable non-destructive instrument for understanding and avoiding degradation in solid-state lithium-based batteries.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1F1A1063093)the Fundamental R&D program through the Korea Institute of Ceramic Engineering&Technology(KICET)(grant NTIS no.1415187241,KPB23003)。
文摘Inadequate interfacial contact between lithium and solid-state electrolytes(SSEs)leads to elevated impedance and the growth of lithium dendrites,presenting significant obstacles to the practical viability of solid-state batteries(SSBs).To ameliorate interfacial contact,optimizing the surface treatment of SSEs has been widely adopted.However,the formation of LiCl through acid treatment,an equally crucial factor impacting SSB performance,has received limited attention,leaving its underlying mechanism unclear.Our study aims to shed light on SSE characteristics following LiCl formation and the removal of Li_(2)CO_(3) through acid treatment.We seek to establish quantifiable links between SSE surface structure and SSB performance,focusing on interfacial resistance,current distribution,critical current density(CCD),and lithium deposition.The formation of LiCl,occurring as Li_(2)CO_(3) is removed through acid treatment,effectively mitigates lithium dendrite formation on SSE surfaces.This action inhibits electron injection and reduces the diffusion rate of Li atoms.Simultaneously,acid treatment transforms the SSE surface into a lithiophilic state by eliminating surface Li_(2)CO_(3).Consequently,the interfacial resistance between lithium and SSEs substantially decreases from 487.67 to 35.99Ωcm^(2) at 25°C.This leads to a notably high CCD of 1.3 mA cm^(-2) and a significantly extended cycle life of 1,000 h.Furthermore,in full SSBs incorporating LiCoO_(2)cathodes and acid-treated garnet SSEs,we observe exceptional cyclability and rate capability.Our findings highlight that acid treatment not only establishes a fundamental relationship between SSE surfaces and battery performance but also offers an effective strategy for addressing interfacial challenges in SSBs.
基金supported by the National Research Foundation grants funded by the Ministry of Science and ICT of Korea(2021M3H4A3A02086211 and RS-2023-00217581).
文摘Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on FEC.Unprecedented stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only additive.DAMS-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs.
基金supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(RS-2023-00303581,Multiscale Simulation-Driven Development of Cost-Effective and Stable Aqueous Zn Ion Battery with Energy Density of 110 Wh/L for Energy Storage Systems:A Korea-USA Collaboration)。
文摘Over the years,zinc-ion batteries(ZIBs)have attracted attention as a promising next-generation energy storage technology because of their excellent safety,long cycling performance,eco-friendliness,and high-power density.However,issues,such as the corrosion and dissolution of the Zn anode,limited wet-tability,and lack of sufficient nucleation sites for Zn plating,have limited their practical application.The introduction of a protective layer comprising of tellurium(Te)nanobelts onto the surface of Zn anode has emerged as a promising approach to overcome these limitations and improve the electrochemical behav-ior by enhancing the safety and wettability of ZIBs,as well as providing numerous nucleation sites for Zn plating.In the presence of a Te-based protective layer,the energy power density of the surface-engineered Zn anode improved significantly(ranging from 310 to 144 W h kg^(-1),over a power density range of 270 to 1,800 W kg^(-1)),and the lifespan capability was extended.These results demonstrate that the proposed strategy of employing Te nanobelts as a protective layer holds great promise for enhancing the energy storage performance of zIBs,making them even more attractive as a viable energy storage solution forthefuture.
基金supported by Nano·Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(2022M3H4A1A04076667)
文摘Bi_(2)Te_(3)-based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature.However,the stability of existing n-type Bi_(2)(Te,Se)_(3)materials is still low due to the evaporation energy of Se(37.70 kJ mol^(-1))being much lower than that of Te(52.55 kJ mol^(-1)).The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency.Here,we have developed a new approach for the high-performance and stable n-type Se-free Bi_(2)Te_(3)-based materials bymaximizing the electronic transport while suppressing the phonon transport,at the same time.Spontaneously generated FeTe_(2)nanoinclusions within the matrix during the melt-spinning and subsequent spark plasma sintering is the key to simultaneous engineering of the power factor and lattice thermal conductivity.The nanoinclusions change the fermi level of the matrix while intensifying the phonon scattering via nanoparticles.With a fine-tuning of the fermi level with Cu doping in the n-type Bi_(2)Te_(3)-0.02FeTe_(2),a high power factor of∼41×10^(-4)Wm^(-1)K^(-2)with an average zT of 1.01 at the temperature range 300-470 K are achieved,which are comparable to those obtained in n-type Bi_(2)(Te,Se)_(3)materials.The proposed approach enables the fabrication of high-performance n-type Bi_(2)Te_(3)-based materials without having to include volatile Se element,which guarantees the stability of the material.Consequently,widespread application of thermoelectric devices utilizing the n-type Bi_(2)Te_(3)-based materials will become possible.
基金funded by the Shanghai Academic/Technology Research Leader(Project No.21XD1432000).
文摘The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,leading to the destruction of the coating layers.Investigating how carbon content affects element diffusion in silicon carbide-based TRISO composite fuel is of great significance for predicting reactor safety.In this study,silicon carbide-based TRISO composite fuels with different carbon contents were prepared by adding varying amounts of phenolic resin to the silicon carbide matrix.X-ray Diffraction(XRD)and Scanning Electron Microscopy(SEM)were employed to characterize the phase composition,morphology,and microstructure of the composite fuels.The elemental content in each coating layer of TRISO was quantified using Energy-Dispersive X-ray Spectroscopy(EDS).The results demonstrated that the addition of phenolic resin promoted the uniform distribution of sintering aids in the silicon carbide matrix.The atomic percentage(at.%)of aluminum(Al)in the pyrolytic carbon layer of the TRISO particles reached its lowest value of 0.55%when the phenolic resin addition was 1%.This is because the addition of phenolic resin caused the Al and silicon(Si)in the matrix to preferentially react with the carbon in the phenolic resin to form a metastable liquid phase,rather than preferentially consuming the pyrolytic carbon in the outer coating layer of the TRISO particles.The findings suggest that carbon addition through phenolic resin incorporation can effectively mitigate the deleterious reactions between the TRISO coating layers and sintering aids,thereby enhancing the durability and safety of silicon carbide-based TRISO composite fuels.
基金supported by the Technology Innovation Program(Grant no.20009985,Grant no.20026752)funded By the Ministry of Trade,Industry&Energy(MOTIE,Korea)。
文摘All-solid-state batteries(ASSBs)are pursued due to their potential for better safety and high energy density.However,the energy density of the cathode for ASSBs does not seem to be satisfactory due to the low utilization of active materials(AMs)at high loading.With small amount of solid electrolyte(SE)powder in the cathode,poor electrochemical performance is often observed due to contact loss and non-homogeneous distribution of AMs and SEs,leading to high tortuosity and limitation of lithium and electron transport pathways.Here,we propose a novel cathode design that can achieve high volumetric energy density of 1258 Wh L^(-1)at high AM content of 85 wt%by synergizing the merits of AM@SE core–shell composite particles with conformally coated thin SE shell prepared from mechanofusion process and small SE particles.The core–shell structure with an intimate and thin SE shell guarantees high ionic conduction pathway while unharming the electronic conduction.In addition,small SE particles play the role of a filler that reduces the packing porosity in the cathode composite electrode as well as between the cathode and the SE separator layer.The systematic demonstration of the optimization process may provide understanding and guidance on the design of electrodes for ASSBs with high electrode density,capacity,and ultimately energy density.
基金supported by the Korean Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea Government(MOTIE)(RS-2023-00303581,Multiscale Simulation-Driven Development of Cost-Effective and Stable Aqueous Zn Ion Battery with Energy Density of 110 Wh/L for Energy Storage Systems:A Korea-USA Collaboration)。
文摘Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and unstable surface electrochemistry.This study introduces a practical method for scattering untreated bulk hexagonal boron nitride(h-BN)particles onto the zinc anode surface.During cycling,stabilized zinc fills the interstices of scattered h-BN,resulting in a more favorable(002)orientation.Consequently,zinc dendrite formation is effectively suppressed,leading to improved electrochemical stability.The zinc with scattered h-BN in a symmetric cell configuration maintains stability 10 times longer than the bare zinc symmetric cell,lasting 500 hours.Furthermore,in a full cell configuration withα-MnO_(2) cathode,increased H^(+)ion activity can effectively alter the major redox kinetics of cycling due to the presence of scattered h-BN on the zinc anode.This shift in H^(+)ion activity lowers the overall redox potential,resulting in a discharge capacity retention of 96.1%for 300 cycles at a charge/discharge rate of 0.5 Ag^(-1).This study highlights the crucial role of surface modification,and the innovative use of bulk h-BN provides a practical and effective solution for improving the performance and stability.
基金Project supported by the Energy & Resource R&D Program under the Ministry of Knowledge Economy,Republic of Korea (2008-R-RU02-P-02-0-000)
文摘Cerium was extracted from rare earth slurry waste used for polishing a glass substrate.Initially,glass frit and flocculant were removed by froth flotation and dissolution.The recovered rare earth slurry exhibited almost the same particle size distribution as original slurry,which could be reused as slurry for glass polishing.From the rare earth slurry,the cerium solution was obtained by an oxidative thermal treatment and subsequent chemical leaching.The cerium solution was further purified up to 94% by selective precipitation of rare earth species.
基金Supported by the National Research Foundation of Korea Grant funded by the Korean Government,No.2014R1A5A2010008
文摘AIM To investigate histologic abnormalities in the gastric smooth muscle of patients with diabetes mellitus(DM).METHODS Full-thickness gastric specimens were obtained from patients undergoing surgery for gastric cancer. H&E stain and Masson's Trichrome stain were performed to assess the degree of fibrosis. Immunohistochemical staining using various antibodies was also performed [antibodies against protein gene product 9.5(PGP9.5), neuronal nitric oxide synthase(n NOS), vasoactive intestinal peptide(VIP), neurokinin-1(NK1) receptor, c-Kit, and platelet-derived growth factor receptor-alpha,(PDGFRα)]. Immunofluorescent staining and evaluation with confocal microscopy were also conducted.RESULTS Twenty-six controls and 35 diabetic patients(21 shortduration patients and 14 long-duration patients) were included. There were no significant differences in basic demographics between the two groups except in mean body mass index(BMI)(higher in the DM group). Proportions of moderate-to-severe intercellular fibrosis in the muscle layer were significantly higher in the DM group than in the control group(P < 0.01). On immunohistochemical staining, c-Kit- and PDGFRα-positive immunoreactivity were significantly decreased in the DM group compared with the control group(P < 0.05). There were no statistically significant differences in PGP9.5, n NOS, VIP, and neurokinin 1 expression. On immunofluorescent staining, cellularity of interstitial cells of Cajal(ICC) was observed to decrease with increasing duration of DM.CONCLUSION Our study suggests that increased intercellular fibrosis, loss of ICC, and loss of fibroblast-like cells are found in the smooth muscle of DM patients. These abnormalities may contribute to changes in gastric motor activity in patients with DM.
基金supported financially by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(No.2017R1D1A1B03030796).
文摘Approaches for the fabrication of a low power-operable formaldehyde(HCHO)gas sensor with high sensitivity and selectivity were performed by the utilization of an effective micro-structured platform with a micro-heater to reach high temperature with low heating power as well as by the integration of indium oxide(In2O3)nanofibers decorated with well-dispersed Au nanoparticles as a sensing material.Homogeneous In2O3 nanofibers with the large specific surface area were prepared by the electrospinning following by calcination process.Au nanoparticles with the well-controlled size as a catalyst were synthesized on the surface of In2O3 nanofibers.The Au-decorated In2O3 nanofibers were reliably integrated as sensing materials on the bridge-type micro-platform including micro-heaters and micro-electrodes.The micro-platform designed to maintain high temperature with low power consumption was fabricated by a microelectromechanical system(MEMS)technique.The micro-platform gas sensor consisting with Au-In2O3 nanofibers were fabricated effectively to detect HCHO gases with high sensitivity and selectivity.The HCHO gas sensing behaviors were schematically studied as a function of the gas concentration,the size of the adsorbed Au nanoparticles,the applied power to raise the temperature of a sensing part and the kind of target gases.
基金supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy,Korea
文摘Barium titanate (BaTiO3) and silver (Ag) composite film with high dielectric constant was grown at room temperature by an aerosol deposition method.The dielectric constant increases by 0.5 times after adding Ag to the BaTiO3 matrix,compared with pure BaTiO3.The high dielectric constant can be attributed to the percolation effect of Ag inclusions in the BaTiO3 matrix.The Ag was present in the form of discrete layer in the BaTiO3 film.The dielectric properties of BaTiO3 Ag were discussed in detail taking into account the changes in microstructures.
文摘In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/D) process. And, unlike the conventional R/D process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with Ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 ℃. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was <<1 μm. Most Nd2Fe14B particles were enclosed with thin layers of Nd-rich phase. Typical magnetic properties of such powder without eliminating impurity CaO were iHc=～5.9 kOe, Br=～5.5 kG, and (BH)max=～6 MGOe.
基金the Basic Science Research Program of the National Research Foundation(NRF)of Korea(Nos.2019R1A6A1A11053838,2022R1A4A3033528,and 2022R1F1A1063285)Korea Agency for Infrastructure Technology Advancement(KAIA)funded by the Ministry of Land,Infrastructure,and Transport(No.21CTAP-C163795-01)Prof.M.Y.Choi acknowledges the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Ministry of Education(Nos.2019R1A6C1010042 and 2021R1A6C103A427).
文摘The single-pot production of Pd@Pt core-shell structures is a promising approach as it offers large surface area,catalytic capability,and stability.In this work,we established a single-pot process to produce Pd@Pt core-shell nanodendrites with tunable composition,shape and size for optimal electrochemical activity.Pd@Pt nanodendrites with diverse compositions were synthesized by tuning the ratios of Pd and Pt sources in an aqueous environment using cetyltrimethylammonium chloride,which functioned as both the surfactant and the reducing agent at an elevated temperature(90°C).The synthesized Pd5@Pt5 nanodendrites showed exceptional electrochemical action toward the methanol oxidation reaction related with another compositional Pd@Pt nanodendrites and conventional Pt/C electrocatalysts.In addition,Pd5@Pt5 nanodendrites exhibited good CO tolerance owing to their surface features and the synergistic effect among Pt and Pd.Meanwhile,nanodendrites with a Pt-rich surface provided exceptional catalytic active sites.Compared with the conventional Pt/C electrocatalyst,the anodic peak current obtained by Pd5@Pt5 nanodendrites was 3.74 and 2.18 times higher in relations of mass and electrochemical active surface area-normalized current density,respectively.This approach offers an attractive strategy to design electrocatalysts with unique structures and outstanding catalytic performance and stability for electrochemical energy conversion.
基金Funded by the National Natural Science Foundation of China (No. 20633090)Shanghai Nano-Science Program (No. 0552nm030)
文摘An approach named ＂pore structure collapsed replication route＂ has been developed to prepare mesoporous WC materials with a high surface area （105 m2/g） and crystallized framework at a temperature as low as 700 ℃. The XRD, TEM, EDS, and BET characterizations were conducted to analyze the effects of the synthesis parameters and the template types on the structure of mesoporous WC. The compaction on the templates is the key to form mesoporous structure of WC while the templates help to control the size of crystalline. At a content of 7 wt% for the precursor of WC, the mesoporous WC could be formed with well ordered structure.
文摘In order to provide the kinetic mechanism for optimizing the quality of the hydroxyapatite （Ca 10（PO4）6-（OH）2, HA） coating on Ti-alloy orthopedic devices, the high temperature behavior of HA-titania （TiO2） composite specimen was investigated using XRD, FTIR and 31P MAS NMR methods. Thermal treatment of HA-TiO2 mixture powders leads to dehydroxylate and decompound of HA as well as chemical reaction between the two materials. Evidence for the initiation of the dehydroxylation of hydroxyapatite was found at 700℃ in air. The decomposition product of β-tricalcium phosphate was proven at 900℃ in air. Additionally, the formation of CaTiO3, derived from the chemical reaction between HA and titania at 900℃, was confirmed.
基金financially supported by the German Research Foundation ( DFG ) in frame of the Collaborative Research Center 920
文摘New carbon bonded filters with “active and reactive coatings ” for higher filtration efficiency of alumina based inclusions as well as nano-engineered filters with nano-scaled additives are explored with the aid of impingement tests and are evaluated according to their cold crushing strengths at room temperature. The combination of carbon nanotubes and alumina nanosheets additives leads to in situ formation of Al3 CON. Both the nanoscaled additives as well as the extra alumina “active”coating lead to improved mechanical performance of the carbon bonded filters and open the horizon for filter macrostructures with higher filtration capacities in means of bigger dimensions. In a further step MWCNT（ multi walled carbon nanotubes） in combination with a synthetic pitch have been used as a functional coating on the surface of alumina carbon bonded filters. These filters have then been evaluated also with uncoated filters in a special casting simulator and the interactions between steel and filtering material have been investigated.
基金The German Research Foundation(DFG)(Grant No.AN 322/27-1,AN 322/19-1,and AN 322/17-2)
文摘The corrosion of refractory crucibles by a highly cor- rosive steel （18CrNiMo7-6） with a high aluminum con- tent and casting temperature of 1 580℃ was investiga- ted. The tested refractories were alumina, muUite and alumina doped with zirconia and titania （ AZT）. The samples were decreasingly attacked in the sequence AZT, alumina and mullite with corrosion layers of about 14, 6 and 1 mm, respectively. In the alumina and AZT, compositions corresponding to manganese aluminates and subsequently manganese aluminosilicates formed with manganese and silicon from the steel. In the mullite cru- cible, compositions corresponding to manganese aluminosilicates formed directly with manganese from the steel giving a highly viscous interfacial melt which retarded the further corrosion.
基金supported by Korea Research Institute for defense Technology planning and advancement(KRIT)grant funded by the Korea government(Defense Acquisition Program Administration(DAPA))(No.21-107-D00-009,Design and development of core materials and unit cells for seawater secondary batteries,2025).
文摘The development of electrolytes with high ionic conductivity and stable electrode–electrolyte interfaces is crucial for the practical realization of solid-state sodium batteries.In this study,the effect of heteroatom doping in a von-Alpen-type Na super ionic conductor(NASICON)was investigated by substituting Zr^(4+)with Mg^(2+),Zn^(2+),and La^(3+)to enhance its material properties and evaluate its potential for solid-state sodium battery applications.Computational chemistry was employed to predict the thermodynamic stability influenced by dopant introduction and the changes in ionic conductivity arising from crystal structure distortion,with the predictions validated by experiments.The optimized Zn^(2+)-doped NASICON(Zn-NZSP0.07)exhibited the highest total ionic conductivity of 2.74×10^(−3)S∙cm^(−1),representing a 4.5-fold increase compared with undoped NASICON(6.00×10−4 S∙cm^(−1)).The material also showed a high relative density of 99.1%,indicating a compact and well-sintered microstructure,as confirmed by a three-point bending test.Furthermore,a high critical current density of 1.4 mA∙cm^(−2)was achieved in symmetric cell testing.Additionally,a Na_(3)V_(2)(PO_(4))_(3)||Zn-NZSP0.07||Na cell delivered an initial capacity of 103.9 mAh∙g^(−1)at 0.1 A∙g^(−1)and retained 73.4%of its capacity after 200 cycles.These results demonstrate that optimal heteroatom doping is crucial for enhancing the performance of NASICON.
