This study explores the potential of Michelia champaca wood as a sustainable and locally available precursor for the fabrication of high-performance supercapacitor electrodes.Activated carbons were synthesized through...This study explores the potential of Michelia champaca wood as a sustainable and locally available precursor for the fabrication of high-performance supercapacitor electrodes.Activated carbons were synthesized through single-step carbonization at 400℃ and 500℃(SSC-400℃ and SSC-500℃) and double-step carbonization at 400℃(DSC-400℃),with all samples activated using H_(3)PO_(4).The effects of carbonization stratergy on the structural,morphological,and electrochemical characteristics of the resulting carbon materials were systematically evaluated,using techniques such as BET,SEM,TEM,XRD,Raman scattering,FTIR,CV,GCD and EIS.Among the samples,SSC-400℃ exhibited the best electrochemical performance,achieving a specific capacitance of 292.2 Fg^(-1),an energy density of 6.4 Wh kg^(-1),and a power density of 198.4 W kg^(-1).This superior performance is attributed to its optimized pore structure,improved sur-face functionality and enhanced conductivity.SSC-500℃showed marginally lower performance,whereas,DSC-400℃ displayed the least favorable results,indicating that double-step carbonization process may negatively affect material quality by disrupting the pore network.This work highlights a strong correlation between synthesis methodology and electrochemical efficiency,directly reinforcing the importance of process optimization in electrode material develop-ment.The findings contribute to the broader goal of developing cost-effective,renewable and environmentally friendly energy storage systems.By valorizing biomass waste,the study supports global movements toward green energy technologies and circular carbon economies,offering a viable pathway for sustainable supercapacitor development and practical applications in energy storage devices.展开更多
In order to address the current inability of screen printing to monitor printing pressure online,an online printing pressure monitoring system applied to screen printing machines was designed in this study.In this stu...In order to address the current inability of screen printing to monitor printing pressure online,an online printing pressure monitoring system applied to screen printing machines was designed in this study.In this study,the consistency of printed electrodes was measured by using a confocal microscope and the pressure distribution detected by online pressure monitoring system was compared to investigate the relationship.The results demonstrated the relationship between printing pressure and the consistency of printed electrodes.As printing pressure increases,the ink layer at the corresponding position becomes thicker and that higher printing pressure enhances the consistency of the printed electrodes.The experiment confirms the feasibility of the online pressure monitoring system,which aids in predicting and controlling the consistency of printed electrodes,thereby improving their performance.展开更多
As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation ...As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries.展开更多
The oil-based mud(OBM) borehole measurement environment presents significant limitations on the application of existing electrical logging instruments in high-resistance formations. In this paper, we propose a novel l...The oil-based mud(OBM) borehole measurement environment presents significant limitations on the application of existing electrical logging instruments in high-resistance formations. In this paper, we propose a novel logging method for detection of high-resistance formations in OBM using highfrequency electrodes. The method addresses the issue of shallow depth of investigation(DOI) in existing electrical logging instruments, while simultaneously ensuring the vertical resolution. Based on the principle of current continuity, the total impedance of the loop is obtained by equating the measurement loop to the series form of a capacitively coupled circuit. and its validity is verified in a homogeneous formation model and a radial two-layer formation model with a mud standoff. Then, the instrument operating frequency and electrode system parameters were preferentially determined by numerical simulation, and the effect of mud gap on impedance measurement was investigated. Subsequently, the DOI of the instrument was investigated utilizing the pseudo-geometric factor defined by the real part of impedance. It was determined that the detection depth of the instrument is 8.74 cm, while the effective vertical resolution was not less than 2 cm. Finally, a focused high-frequency electrode-type instrument was designed by introducing a pair of focused electrodes, which effectively enhanced the DOI of the instrument and was successfully deployed in the Oklahoma formation model. The simulation results demonstrate that the novel method can achieve a detection depth of 17.40 cm in highly-resistive formations drilling with OBM, which is approximately twice the depth of detection of the existing oil-based mud microimager instruments. Furthermore, its effective vertical resolution remains at or above 2 cm,which is comparable to the resolution of the existing OBM electrical logging instrument.展开更多
In a pulsed plasma thruster,the voltage distribution between the electrodes is a key factor that influences the ionization process.However,few researchers have conducted in-depth studies of this phenomenon in the past...In a pulsed plasma thruster,the voltage distribution between the electrodes is a key factor that influences the ionization process.However,few researchers have conducted in-depth studies of this phenomenon in the past.Reported here are measurements of the voltage distribution between the plates of a parallel-plate pulsed plasma thruster under different discharge voltages,based on which the variations in the total circuit inductance and resistance as well as those between the plates are calculated.The results show that the time-averaged voltage across the plates accounts for 28.7%-50.4%of the capacitor voltage.As the capacitor initial voltage increases from 1250 V to 2000 V,the voltage across the plates rises,but its proportion relative to the capacitor voltage decreases.For every 250 V increase in the capacitor initial voltage,the average voltage proportion across the plates decreases by approximately 2%-3%.Additionally,the voltage proportion decreases gradually from the end near the propellant outward.The voltage distribution ratio between the plates is correlated with the proportions of the resistance and inductance between the plates relative to the total circuit.展开更多
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata...The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.展开更多
Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were succ...Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were successfully synthesized by hydrothermal,annealing and phosphating methods on nickel foam(NF).The unusual shape of the sea urchin facilitates gas release and mass transfer and increases the interaction between catalysts and electrolytes.The Ni_(4)Mo/NF and Ni-Mo-P/NF electrodes only need overpotentials of 72 and 197 mV to reach 50 mA·cm^(−2) under alkaline conditions for hydrogen evolution reaction and oxygen evolution reaction,respectively.The Ni_(4)Mo/NF and Ni-Mo-P/NF asymmetric electrodes were used as anode and cathode for the overall water splitting,respectively.In 1.0 M KOH,at a voltage of 1.485 V,the electrolytic device generated 50 mA·cm^(−2) current density,maintaining for 24 h without reduction.The labor presents a simple method to synthesize a highly active,low-cost,and strongly durable self-supporting electrode for over-water splitting.展开更多
Supercapacitors are efficient and versatile energy storage devices,offering remarkable power density,fast charge/discharge rates,and exceptional cycle life.As research continues to push the boundaries of their perform...Supercapacitors are efficient and versatile energy storage devices,offering remarkable power density,fast charge/discharge rates,and exceptional cycle life.As research continues to push the boundaries of their performance,electrode fabrication techniques are critical aspects influencing the overall capabilities of supercapacitors.Herein,we aim to shed light on the advantages offered by dry electrode processing for advanced supercapacitors.Notably,our study explores the performance of these electrodes in three different types of electrolytes:organic,ionic liquids,and quasi-solid states.By examining the impact of dry electrode processing on various electrode and electrolyte systems,we show valuable insights into the versatility and efficacy of this technique.The supercapacitors employing dry electrodes demonstrated significant improvements compared with conventional wet electrodes,with a lifespan extension of+45%in organic,+192%in ionic liquids,and+84%in quasi-solid electrolytes.Moreover,the increased electrode densities achievable through the dry approach directly translate to improved volumetric outputs,enhancing energy storage capacities within compact form factors.Notably,dry electrode-prepared supercapacitors outperformed their wet electrode counterparts,exhibiting a higher energy density of 6.1 Wh cm^(-3)compared with 4.7 Wh cm^(-3)at a high power density of 195Wcm^(-3),marking a substantial 28%energy improvement in the quasi-solid electrolyte.展开更多
In pursuit of meeting the demands for the next generation of high energy density and flexible electronic products,there is a growing interest in flexible energy storage devices.Silicon(Si)stands out as a promising ele...In pursuit of meeting the demands for the next generation of high energy density and flexible electronic products,there is a growing interest in flexible energy storage devices.Silicon(Si)stands out as a promising electrode material due to its high theoretical specific capacity(~3579 mA h g^(-1)),low lithiation potential(~0.40 V),and abundance in nature.We have successfully developed freestanding and flexible CNT/Si/low-melting-point metal(LM)electrodes,which obviate the need for conductive additives,adhesives,and thereby increase the energy density of the device.As an anode material for lithium-ion batteries(LIBs),the CNT/Si/LM electrode demonstrates remarkable cycling stability and rate performance,achieving a reversible capacity of 1871.8 mA h g^(-1)after 100 cycles at a current density of 0.2 A g^(-1).In-situ XRD and in-situ thickness analysis are employed to elucidate the underlying mechanisms during the lithiation/delithiation.Density functional theory(DFT)calculations further substantiate the mechanism by which LM enhances the electrochemical performance of Si,focusing on the aspects of stress mitigation and reduction of the diffusion energy barrier.This research introduces a novel approach to flexible electrode design by integrating CNT films,LM,and Si,thereby charting a path forward for the development of next-generation flexible LIBs.展开更多
The silicon-graphite(Si-C)composite electrode is considered a promising candidate for next-generation commercial electrodes due to its high capacity.However,lithium-ion batteries with silicon electrodes often experien...The silicon-graphite(Si-C)composite electrode is considered a promising candidate for next-generation commercial electrodes due to its high capacity.However,lithium-ion batteries with silicon electrodes often experience capacity fading and poor cyclic performance,primarily due to the mechanical degradation of the solid-electrolyte interphase(SEI).In this work,we present a homogenized constitutive model for Si-C composite electrodes under finite deformation,incorporating lithium-ion concentration-dependent properties.We perform a wrinkling analysis and systematically examine the influence of key parameters,such as modulus and thickness ratios,on the critical conditions for instability.Additionally,we investigate the ratcheting effect across varying silicon contents.Our findings reveal that maintaining the silicon content within an optimal range effectively reduces plastic accumulation during charge–discharge cycles.These insights provide crucial guidance for optimizing the design and fabrication of Si–C electrode systems,enhancing their durability and performance.展开更多
A novel characterization method for full-matrix constants of PzT-8 piezoceramics based on local electrodes excitation using one sample is proposed to avoid resonant peaks missing and overlapping in the inversion proce...A novel characterization method for full-matrix constants of PzT-8 piezoceramics based on local electrodes excitation using one sample is proposed to avoid resonant peaks missing and overlapping in the inversion process of resonant ultrasound spectroscopy technology.Elastic matrix,which is sensitive to the resonance spectrum,is obtained by resonant ultrasound spectroscopy.Piezoelectric and dielectric matrices,which are sensitive to the capacitance of driving electrodes,are determined by capacitance inversion.The initial values of elastic constants are deviated by 30%to validate the reliability of this method.The relative errors between measured and inversed values of resonant frequencies are less than 1%and the relative errors of the capacitance are mostly less than 5%.The work has extensive applications in piezoelectric materials characterization.展开更多
Amidst the ever-growing interest in high-mass-loading Li battery electrodes,a persistent challenge has been the insufficient continuity of their ion/electron conduction pathways.Here,we propose cellulose elementary fi...Amidst the ever-growing interest in high-mass-loading Li battery electrodes,a persistent challenge has been the insufficient continuity of their ion/electron conduction pathways.Here,we propose cellulose elementary fibrils(CEFs)as a class of deagglomerated binder for high-mass-loading electrodes.Derived from natural wood,CEF represents the most fundamental unit of cellulose with nanoscale diameter.The preparation of the CEFs involves the modulation of intermolecular hydrogen bonding by the treatment with a proton acceptor and a hydrotropic agent.This elementary deagglomeration of the cellulose fibers increases surface area and anionic charge density,thus promoting uniform dispersion with carbon conductive additives and suppressing interfacial side reactions at electrodes.Consequently,a homogeneous redox reaction is achieved throughout the electrodes.The resulting CEF-based cathode(overlithiated layered oxide(OLO)is chosen as a benchmark electrode active material)exhibits a high areal-mass-loading(50 mg cm^(-2),equivalent to an areal capacity of 12.5 mAh cm^(-2))and a high specific energy density(445.4 Wh kg–1)of a cell,which far exceeds those of previously reported OLO cathodes.This study highlights the viability of the deagglomerated binder in enabling sustainable high-mass-loading electrodes that are difficult to achieve with conventional synthetic polymer binders.展开更多
Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Neve...Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Nevertheless,the widespread applications of SOCs are remarkably restricted by the inferior stability and high material costs induced by the high operational temperatures(600-800℃).Tremendous research efforts have been devoted to suppressing the operating temperatures of SOCs to decrease the overall costs and enhance the long-term durability.However,fuel electrodes as key components in SOCs suffer from insufficient(electro)catalytic activity and inferior impurity tolerance/redox resistance at reduced temperatures.Nanostructures and relevant nanomaterials exhibit great potential to boost the performance of fuel electrodes for low-temperature(LT)-SOCs due to the unique surface/interface properties,enlarged active sites,and strong interaction.Herein,an in-time review about advances in the design and fabrication of nanostructured fuel electrodes for LT-SOCs is presented by emphasizing the crucial role of nanostructure construction in boosting the performance of fuel electrodes and the relevant/distinct material design strategies.The main achievements,remaining challenges,and research trends about the development of nanostructured fuel electrodes in LT-SOCs are also presented,aiming to offer important insights for the future development of energy storage/conversion technologies.展开更多
Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chem...Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.展开更多
All-solid-state rechargeable air batteries are designed and fabricated using 1,4-naphthoquinone as a negative electrode,proton-conductive polymer membrane as a solid electrolyte,and platinum-based oxygen diffusion as ...All-solid-state rechargeable air batteries are designed and fabricated using 1,4-naphthoquinone as a negative electrode,proton-conductive polymer membrane as a solid electrolyte,and platinum-based oxygen diffusion as a positive electrode as an emerging energy device.1,4-Naphthoquinone molecules exhibit reversible redox reactions peaked at 0.28 and 0.52 V versus reversible hydrogen electrode with the polymer electrolyte similar to that in an acid aqueous solution.The all-solid-state rechargeable air battery cell shows an open circuit voltage of 0.83 V,a nominal voltage of 0.3-0.4 V,a discharge capacity of 83.6 mAh g^(-1),and an initial Coulombic efficiency of 86.8%.The Coulombic efficiency after 15 charge-discharge cycles improves from 57.3%to 69.1%by replacing carbon black with graphite carbon as a support for the platinum catalyst in the positive electrode.Furthermore,replacing the commercial Nafion electrolyte membrane with the synthesized(in-house)polyphenylene-based ionomer(sulfonated polyphenylene-quinquephenylene)electrolyte membrane improves the cycle durability of the resulting allsolid-state rechargeable air battery with high Coulombic efficiency retention(>98%)after 135 cycles owing to the lower oxygen permeability of the latter membrane.Overall,the present all-solid-state rechargeable air battery using 1,4-naphthoquinone outperforms our previous all-solid-state rechargeable air battery using dihydroxybenzoquinene as a redox-active molecule.展开更多
This work describes the discharge characteristics and acetone degradation with plasma under different electric fields based on a coaxial cylindrical dielectric barrier discharge(DBD)device energized by pulsed power.It...This work describes the discharge characteristics and acetone degradation with plasma under different electric fields based on a coaxial cylindrical dielectric barrier discharge(DBD)device energized by pulsed power.It is found that the segmented electrodes with appropriate spacing in coaxial cylindrical DBD are beneficial to the plasma ionization.In this work,the plasma distribution,discharge thermal effect,ionization of reactive species,and acetone degradation performance in coaxial cylindrical DBD with different segmented electrodes are systematically investigated.The experimental results show that segmented electrodes with a certain distance can cause additional ionization in the non-electrode-covered region between adjacent electrodes,thus enlarging the plasma region compared with a single electrode with equivalent total electrode length.The additional ionization involved the inner volume discharge between the quartz tubes and the outer surface discharge along the surface of the external quartz tube.The spatial distributions of the inner volume discharge and external surface discharge were predominantly governed by the radial and axial components of the inter-electrode electric field,respectively.The external surface discharge exhibited significant suppression when the electrode spacing was<1.5 mm,and it reached its maximum length at 3 mm spacing.When the electrode distance increased to 7-9 mm,a weak ionizing region appeared in the middle of the adjacent electrodes,which could be attributed to the gradual attenuation of the radial component with the increasing electrode spacing.A higher thermal effect and better oxidation of acetone to CO_(x)(CO and CO_(2))were achieved with the segmented electrode;the dual-segment configuration(3 mm per electrode)achieved a reactor temperature of 63.4℃,representing a 10℃enhancement over comparable single-electrode systems.Similarly,the CO_(2)and CO concentration reached 328.8 mg/m3and 105.7 mg/m3,respectively,in two 3 mm long segmented electrodes,which was an increase of 12.2%and 25.6%,respectively,compared with the single electrode.Notably,considering the equivalent ionization of the inner discharge with different electrodes,the enhanced thermal effects and CO_(x)conversion efficiency directly correlate with the expanded plasma zone induced by electrode segmentation.This work provides critical insights into optimizing electrode configurations for efficient plasma-assisted volatile organic compound degradation systems.展开更多
Silicon monoxide(SiO)is highly attractive as an anode material for high-energy lithium-ion batteries(LIBs)due to its significantly higher specific capacity.However,its practical application is hindered by substantial ...Silicon monoxide(SiO)is highly attractive as an anode material for high-energy lithium-ion batteries(LIBs)due to its significantly higher specific capacity.However,its practical application is hindered by substantial volume expansion during cycling,which leads to material pulverization and an unstable solid electrolyte interphase(SEI)layer.Inspired by the natural root fixation in soil,we designed a root-like topological structure binder,cassava starch-citric acid(CS-CA),based on the synergistic action of covalent and hydrogen bonds.The abundant-OH and-COOH groups in CS-CA molecules effectively form hydrogen bonds with the-OH groups on the SiO surface,significantly enhancing the interfacial interaction between CS-CA and SiO.The root-like topological structure of CS-CA with a high tolerance alleviates the mechanical stress generated by the volume changes of SiO.More encouragingly,the hydrogen bond action among CS-CA molecules produces a self-healing effect,which is advantageous for repairing damaged electrodes and preserving their structural integrity.As such,the CS-CA/SiO electrode exhibits exceptional cycling performance(963.1 mA h g^(-1)after 400 cycles at 2 A g^(-1))and rate capability(558.9 mA h g^(-1)at 5 A g^(-1)).This innovative,topologically interconnected,root-inspired binder will greatly advance the practical application of long-lasting micron-sized SiO anodes.展开更多
The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systema...The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systematic replacement of metallic structural support components(MSSCs)to minimize non-active constituent ratios,contingent upon maintaining robust interfacial contact integrity among electrodes,separators,and battery shells.Herein,we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode(UCFxC)to achieve complete MSSCs elimination.The engineered UCFxC demonstrates exceptional areal capacity metrics(249.45 mg cm^(-2),215.77 m Ah cm^(-2)),enabling a 27.8% mass reduction compared with conventional laboratoryassembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity.Notably,single-walled carbon nanotube(SWCNT)-modified UCFxC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50℃.This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems,with practical implications for advancing miniaturized power source technologies.展开更多
Radiofrequency ablation(RFA)is a form of minimally invasive procedure that precisely ablates abnormal lesions or hyperplastic tissues through thermal energy generated by the radiofrequency current at the tip electrode...Radiofrequency ablation(RFA)is a form of minimally invasive procedure that precisely ablates abnormal lesions or hyperplastic tissues through thermal energy generated by the radiofrequency current at the tip electrode of the flexible catheter,which aims to partially or fully restore the function of the corresponding tissues or organs.Accurate prediction and control of thermal fields are crucial for clinical thermal ablation to ensure precise control of the ablation lesion size and prevent excessive burning of healthy tissues.In this study,an axisymmetric analytical model is developed for the electrothermal analysis of RFA in the cambered tissue surface and verified with the finite element analysis(FEA),which incorporates both the thermal field induced by the radiofrequency current and Pennes'biothermal effect.This model utilizes analytically derived electric and thermal fields to accurately predict the increase in the tissue temperature and the time-varying size of ablation lesion in the tissue.Furthermore,the parameters such as the input current density,curvature,and convective heat transfer coefficient of blood have a significant effect on the thermal field and thus the ablation lesion size.This electrothermal analytical model with a large curvature may provide a theoretical foundation and guidance for the future RFA applications on large-curvature biological surfaces,thereby enhancing accuracy,reducing the need for re-ablation,and lowering the costs associated with the design and production of ablation catheters.展开更多
Direct formic acid fuel cells are promising energy devices with advantages of low working temperature and high safety in fuel storage and transport.They have been expected to be a future power source for portable elec...Direct formic acid fuel cells are promising energy devices with advantages of low working temperature and high safety in fuel storage and transport.They have been expected to be a future power source for portable electronic devices.The technology has been developed rapidly to overcome the high cost and low power performance that hinder its practical application,which mainly originated from the slow reaction kinetics of the formic acid oxidation and complex mass transfer within the fuel cell electrodes.Here,we provide a comprehensive review of the progress around this technology,in particular for addressing multiscale challenges from catalytic mechanism understanding at the atomic scale,to catalyst design at the nanoscale,electrode structure at the micro scale and design at the millimeter scale,and finally to device fabrication at the meter scale.The gap between the highly active electrocatalysts and the poor electrode performance in practical devices is highlighted.Finally,perspectives and opportunities are proposed to potentially bridge this gap for further development of this technology.展开更多
文摘This study explores the potential of Michelia champaca wood as a sustainable and locally available precursor for the fabrication of high-performance supercapacitor electrodes.Activated carbons were synthesized through single-step carbonization at 400℃ and 500℃(SSC-400℃ and SSC-500℃) and double-step carbonization at 400℃(DSC-400℃),with all samples activated using H_(3)PO_(4).The effects of carbonization stratergy on the structural,morphological,and electrochemical characteristics of the resulting carbon materials were systematically evaluated,using techniques such as BET,SEM,TEM,XRD,Raman scattering,FTIR,CV,GCD and EIS.Among the samples,SSC-400℃ exhibited the best electrochemical performance,achieving a specific capacitance of 292.2 Fg^(-1),an energy density of 6.4 Wh kg^(-1),and a power density of 198.4 W kg^(-1).This superior performance is attributed to its optimized pore structure,improved sur-face functionality and enhanced conductivity.SSC-500℃showed marginally lower performance,whereas,DSC-400℃ displayed the least favorable results,indicating that double-step carbonization process may negatively affect material quality by disrupting the pore network.This work highlights a strong correlation between synthesis methodology and electrochemical efficiency,directly reinforcing the importance of process optimization in electrode material develop-ment.The findings contribute to the broader goal of developing cost-effective,renewable and environmentally friendly energy storage systems.By valorizing biomass waste,the study supports global movements toward green energy technologies and circular carbon economies,offering a viable pathway for sustainable supercapacitor development and practical applications in energy storage devices.
文摘In order to address the current inability of screen printing to monitor printing pressure online,an online printing pressure monitoring system applied to screen printing machines was designed in this study.In this study,the consistency of printed electrodes was measured by using a confocal microscope and the pressure distribution detected by online pressure monitoring system was compared to investigate the relationship.The results demonstrated the relationship between printing pressure and the consistency of printed electrodes.As printing pressure increases,the ink layer at the corresponding position becomes thicker and that higher printing pressure enhances the consistency of the printed electrodes.The experiment confirms the feasibility of the online pressure monitoring system,which aids in predicting and controlling the consistency of printed electrodes,thereby improving their performance.
基金supported by the Fundamental Research Funds for the Central Universities(WK2090000055)Anhui Provincial Natural Science Foundation of China(2308085QG231).
文摘As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries.
基金the National Natural Science Foundation of China(42074134,42474152,42374150)CNPC Innovation Found(2024DQ02-0152).
文摘The oil-based mud(OBM) borehole measurement environment presents significant limitations on the application of existing electrical logging instruments in high-resistance formations. In this paper, we propose a novel logging method for detection of high-resistance formations in OBM using highfrequency electrodes. The method addresses the issue of shallow depth of investigation(DOI) in existing electrical logging instruments, while simultaneously ensuring the vertical resolution. Based on the principle of current continuity, the total impedance of the loop is obtained by equating the measurement loop to the series form of a capacitively coupled circuit. and its validity is verified in a homogeneous formation model and a radial two-layer formation model with a mud standoff. Then, the instrument operating frequency and electrode system parameters were preferentially determined by numerical simulation, and the effect of mud gap on impedance measurement was investigated. Subsequently, the DOI of the instrument was investigated utilizing the pseudo-geometric factor defined by the real part of impedance. It was determined that the detection depth of the instrument is 8.74 cm, while the effective vertical resolution was not less than 2 cm. Finally, a focused high-frequency electrode-type instrument was designed by introducing a pair of focused electrodes, which effectively enhanced the DOI of the instrument and was successfully deployed in the Oklahoma formation model. The simulation results demonstrate that the novel method can achieve a detection depth of 17.40 cm in highly-resistive formations drilling with OBM, which is approximately twice the depth of detection of the existing oil-based mud microimager instruments. Furthermore, its effective vertical resolution remains at or above 2 cm,which is comparable to the resolution of the existing OBM electrical logging instrument.
基金supported by the Beijing Natural Science Foundation(No.QY24166).
文摘In a pulsed plasma thruster,the voltage distribution between the electrodes is a key factor that influences the ionization process.However,few researchers have conducted in-depth studies of this phenomenon in the past.Reported here are measurements of the voltage distribution between the plates of a parallel-plate pulsed plasma thruster under different discharge voltages,based on which the variations in the total circuit inductance and resistance as well as those between the plates are calculated.The results show that the time-averaged voltage across the plates accounts for 28.7%-50.4%of the capacitor voltage.As the capacitor initial voltage increases from 1250 V to 2000 V,the voltage across the plates rises,but its proportion relative to the capacitor voltage decreases.For every 250 V increase in the capacitor initial voltage,the average voltage proportion across the plates decreases by approximately 2%-3%.Additionally,the voltage proportion decreases gradually from the end near the propellant outward.The voltage distribution ratio between the plates is correlated with the proportions of the resistance and inductance between the plates relative to the total circuit.
基金supported by Guangxi Science and Technology Major Program(No.AA23073008)Hubei Key Laboratory of Water System Science for Sponge City Construction(Wuhan University)(No.2023–05)Nanning Innovation and Entrepreneur Leading Talent Project(No.2021001).
文摘The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.
基金supported by the Natural Science Research Project of Jiangsu Higher Education Institutions(No.23KJD150005)the Scientific Research Project of Nanjing Xiaozhuang University(No.2022NXY29).
文摘Developing efficient and stable electrocatalysts has always been the focus of electrochemical research.Here,sea urchin-like nickel-molybdenum bimetallic phosphide nickel-molybdenum alloy(Ni_(4)Mo)and(Ni-Mo-P)were successfully synthesized by hydrothermal,annealing and phosphating methods on nickel foam(NF).The unusual shape of the sea urchin facilitates gas release and mass transfer and increases the interaction between catalysts and electrolytes.The Ni_(4)Mo/NF and Ni-Mo-P/NF electrodes only need overpotentials of 72 and 197 mV to reach 50 mA·cm^(−2) under alkaline conditions for hydrogen evolution reaction and oxygen evolution reaction,respectively.The Ni_(4)Mo/NF and Ni-Mo-P/NF asymmetric electrodes were used as anode and cathode for the overall water splitting,respectively.In 1.0 M KOH,at a voltage of 1.485 V,the electrolytic device generated 50 mA·cm^(−2) current density,maintaining for 24 h without reduction.The labor presents a simple method to synthesize a highly active,low-cost,and strongly durable self-supporting electrode for over-water splitting.
基金funding of the joint Polish-German project SUPILMIX(PR-1173/27)by the German Research Foundation(DFG,Deutsche Forschungsgemeinschaft)+1 种基金funding from the Alexander von Humboldt Foundation.D.L.the German Chemical Industry Fund for the financial support through a Liebig Fellowship.
文摘Supercapacitors are efficient and versatile energy storage devices,offering remarkable power density,fast charge/discharge rates,and exceptional cycle life.As research continues to push the boundaries of their performance,electrode fabrication techniques are critical aspects influencing the overall capabilities of supercapacitors.Herein,we aim to shed light on the advantages offered by dry electrode processing for advanced supercapacitors.Notably,our study explores the performance of these electrodes in three different types of electrolytes:organic,ionic liquids,and quasi-solid states.By examining the impact of dry electrode processing on various electrode and electrolyte systems,we show valuable insights into the versatility and efficacy of this technique.The supercapacitors employing dry electrodes demonstrated significant improvements compared with conventional wet electrodes,with a lifespan extension of+45%in organic,+192%in ionic liquids,and+84%in quasi-solid electrolytes.Moreover,the increased electrode densities achievable through the dry approach directly translate to improved volumetric outputs,enhancing energy storage capacities within compact form factors.Notably,dry electrode-prepared supercapacitors outperformed their wet electrode counterparts,exhibiting a higher energy density of 6.1 Wh cm^(-3)compared with 4.7 Wh cm^(-3)at a high power density of 195Wcm^(-3),marking a substantial 28%energy improvement in the quasi-solid electrolyte.
基金the National Natural Science Foundation of China(22279070).
文摘In pursuit of meeting the demands for the next generation of high energy density and flexible electronic products,there is a growing interest in flexible energy storage devices.Silicon(Si)stands out as a promising electrode material due to its high theoretical specific capacity(~3579 mA h g^(-1)),low lithiation potential(~0.40 V),and abundance in nature.We have successfully developed freestanding and flexible CNT/Si/low-melting-point metal(LM)electrodes,which obviate the need for conductive additives,adhesives,and thereby increase the energy density of the device.As an anode material for lithium-ion batteries(LIBs),the CNT/Si/LM electrode demonstrates remarkable cycling stability and rate performance,achieving a reversible capacity of 1871.8 mA h g^(-1)after 100 cycles at a current density of 0.2 A g^(-1).In-situ XRD and in-situ thickness analysis are employed to elucidate the underlying mechanisms during the lithiation/delithiation.Density functional theory(DFT)calculations further substantiate the mechanism by which LM enhances the electrochemical performance of Si,focusing on the aspects of stress mitigation and reduction of the diffusion energy barrier.This research introduces a novel approach to flexible electrode design by integrating CNT films,LM,and Si,thereby charting a path forward for the development of next-generation flexible LIBs.
基金supported by the National Natural Science Foundation of China(Grants Nos.12172102 and 12372097)the Fundamental Research Funds for the Central Universities(Grant No.HIT.OCEF.2022013).
文摘The silicon-graphite(Si-C)composite electrode is considered a promising candidate for next-generation commercial electrodes due to its high capacity.However,lithium-ion batteries with silicon electrodes often experience capacity fading and poor cyclic performance,primarily due to the mechanical degradation of the solid-electrolyte interphase(SEI).In this work,we present a homogenized constitutive model for Si-C composite electrodes under finite deformation,incorporating lithium-ion concentration-dependent properties.We perform a wrinkling analysis and systematically examine the influence of key parameters,such as modulus and thickness ratios,on the critical conditions for instability.Additionally,we investigate the ratcheting effect across varying silicon contents.Our findings reveal that maintaining the silicon content within an optimal range effectively reduces plastic accumulation during charge–discharge cycles.These insights provide crucial guidance for optimizing the design and fabrication of Si–C electrode systems,enhancing their durability and performance.
基金the Professional Technical Service Platform of Shanghai Science and Technology Commission(No.19DZ2291103)。
文摘A novel characterization method for full-matrix constants of PzT-8 piezoceramics based on local electrodes excitation using one sample is proposed to avoid resonant peaks missing and overlapping in the inversion process of resonant ultrasound spectroscopy technology.Elastic matrix,which is sensitive to the resonance spectrum,is obtained by resonant ultrasound spectroscopy.Piezoelectric and dielectric matrices,which are sensitive to the capacitance of driving electrodes,are determined by capacitance inversion.The initial values of elastic constants are deviated by 30%to validate the reliability of this method.The relative errors between measured and inversed values of resonant frequencies are less than 1%and the relative errors of the capacitance are mostly less than 5%.The work has extensive applications in piezoelectric materials characterization.
基金supported by the Institute of Civil Military Technology Cooperation funded by the Defense Acquisition Program Administration and Ministry of Trade,Industry and Energy of Korean government under grant No 23-CM-AI-08.
文摘Amidst the ever-growing interest in high-mass-loading Li battery electrodes,a persistent challenge has been the insufficient continuity of their ion/electron conduction pathways.Here,we propose cellulose elementary fibrils(CEFs)as a class of deagglomerated binder for high-mass-loading electrodes.Derived from natural wood,CEF represents the most fundamental unit of cellulose with nanoscale diameter.The preparation of the CEFs involves the modulation of intermolecular hydrogen bonding by the treatment with a proton acceptor and a hydrotropic agent.This elementary deagglomeration of the cellulose fibers increases surface area and anionic charge density,thus promoting uniform dispersion with carbon conductive additives and suppressing interfacial side reactions at electrodes.Consequently,a homogeneous redox reaction is achieved throughout the electrodes.The resulting CEF-based cathode(overlithiated layered oxide(OLO)is chosen as a benchmark electrode active material)exhibits a high areal-mass-loading(50 mg cm^(-2),equivalent to an areal capacity of 12.5 mAh cm^(-2))and a high specific energy density(445.4 Wh kg–1)of a cell,which far exceeds those of previously reported OLO cathodes.This study highlights the viability of the deagglomerated binder in enabling sustainable high-mass-loading electrodes that are difficult to achieve with conventional synthetic polymer binders.
基金supported by the National Key R&D Program of China(No.2022YFB4002502)the National Natural Science Foundation of China(No.22279057)。
文摘Solid oxide cells(SOCs)are attractive electrochemical energy conversion/storage technologies for electricity/green hydrogen production because of the high efficiencies,all-solid structure,and superb reversibility.Nevertheless,the widespread applications of SOCs are remarkably restricted by the inferior stability and high material costs induced by the high operational temperatures(600-800℃).Tremendous research efforts have been devoted to suppressing the operating temperatures of SOCs to decrease the overall costs and enhance the long-term durability.However,fuel electrodes as key components in SOCs suffer from insufficient(electro)catalytic activity and inferior impurity tolerance/redox resistance at reduced temperatures.Nanostructures and relevant nanomaterials exhibit great potential to boost the performance of fuel electrodes for low-temperature(LT)-SOCs due to the unique surface/interface properties,enlarged active sites,and strong interaction.Herein,an in-time review about advances in the design and fabrication of nanostructured fuel electrodes for LT-SOCs is presented by emphasizing the crucial role of nanostructure construction in boosting the performance of fuel electrodes and the relevant/distinct material design strategies.The main achievements,remaining challenges,and research trends about the development of nanostructured fuel electrodes in LT-SOCs are also presented,aiming to offer important insights for the future development of energy storage/conversion technologies.
基金financially supported by the National Postdoctoral Program for Innovative Talents, China (No. BX2021327)the National Natural Science Foundation of China (Nos. 22206194 and U2267222)+1 种基金the Ningbo Natural Science Foundation of China (No. 2023J337)the Yongjiang Talent Introduction Programme, China (No. 2 021A-161-G)。
文摘Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.
基金supported by the Ministry of Education,Culture,Sports,Science and Technology(MEXT),Japan,through Grants-in-Aid for Scientific Research(23H02058)MEXT Program:Data Creation and Utilization Type Material Research and Development Project(JPMXP1122712807)+1 种基金Japan Science and Technology Agency(JST)(GteX JPMJGX23H2)JKA promotion funds from AUTORACE.
文摘All-solid-state rechargeable air batteries are designed and fabricated using 1,4-naphthoquinone as a negative electrode,proton-conductive polymer membrane as a solid electrolyte,and platinum-based oxygen diffusion as a positive electrode as an emerging energy device.1,4-Naphthoquinone molecules exhibit reversible redox reactions peaked at 0.28 and 0.52 V versus reversible hydrogen electrode with the polymer electrolyte similar to that in an acid aqueous solution.The all-solid-state rechargeable air battery cell shows an open circuit voltage of 0.83 V,a nominal voltage of 0.3-0.4 V,a discharge capacity of 83.6 mAh g^(-1),and an initial Coulombic efficiency of 86.8%.The Coulombic efficiency after 15 charge-discharge cycles improves from 57.3%to 69.1%by replacing carbon black with graphite carbon as a support for the platinum catalyst in the positive electrode.Furthermore,replacing the commercial Nafion electrolyte membrane with the synthesized(in-house)polyphenylene-based ionomer(sulfonated polyphenylene-quinquephenylene)electrolyte membrane improves the cycle durability of the resulting allsolid-state rechargeable air battery with high Coulombic efficiency retention(>98%)after 135 cycles owing to the lower oxygen permeability of the latter membrane.Overall,the present all-solid-state rechargeable air battery using 1,4-naphthoquinone outperforms our previous all-solid-state rechargeable air battery using dihydroxybenzoquinene as a redox-active molecule.
文摘This work describes the discharge characteristics and acetone degradation with plasma under different electric fields based on a coaxial cylindrical dielectric barrier discharge(DBD)device energized by pulsed power.It is found that the segmented electrodes with appropriate spacing in coaxial cylindrical DBD are beneficial to the plasma ionization.In this work,the plasma distribution,discharge thermal effect,ionization of reactive species,and acetone degradation performance in coaxial cylindrical DBD with different segmented electrodes are systematically investigated.The experimental results show that segmented electrodes with a certain distance can cause additional ionization in the non-electrode-covered region between adjacent electrodes,thus enlarging the plasma region compared with a single electrode with equivalent total electrode length.The additional ionization involved the inner volume discharge between the quartz tubes and the outer surface discharge along the surface of the external quartz tube.The spatial distributions of the inner volume discharge and external surface discharge were predominantly governed by the radial and axial components of the inter-electrode electric field,respectively.The external surface discharge exhibited significant suppression when the electrode spacing was<1.5 mm,and it reached its maximum length at 3 mm spacing.When the electrode distance increased to 7-9 mm,a weak ionizing region appeared in the middle of the adjacent electrodes,which could be attributed to the gradual attenuation of the radial component with the increasing electrode spacing.A higher thermal effect and better oxidation of acetone to CO_(x)(CO and CO_(2))were achieved with the segmented electrode;the dual-segment configuration(3 mm per electrode)achieved a reactor temperature of 63.4℃,representing a 10℃enhancement over comparable single-electrode systems.Similarly,the CO_(2)and CO concentration reached 328.8 mg/m3and 105.7 mg/m3,respectively,in two 3 mm long segmented electrodes,which was an increase of 12.2%and 25.6%,respectively,compared with the single electrode.Notably,considering the equivalent ionization of the inner discharge with different electrodes,the enhanced thermal effects and CO_(x)conversion efficiency directly correlate with the expanded plasma zone induced by electrode segmentation.This work provides critical insights into optimizing electrode configurations for efficient plasma-assisted volatile organic compound degradation systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.22378342,92372101,52162036,and 21875155)the Fundamental Research Funds for the Central Universities(20720220010)+3 种基金the National Key Research and Development Program of China(2021YFA1201502)the Natural Science Foundation of Sichuan Province(Grant No.2024NSFSC1160)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20230608)support of Nanqiang Young Top-notch Talent Fellowship in Xiamen University。
文摘Silicon monoxide(SiO)is highly attractive as an anode material for high-energy lithium-ion batteries(LIBs)due to its significantly higher specific capacity.However,its practical application is hindered by substantial volume expansion during cycling,which leads to material pulverization and an unstable solid electrolyte interphase(SEI)layer.Inspired by the natural root fixation in soil,we designed a root-like topological structure binder,cassava starch-citric acid(CS-CA),based on the synergistic action of covalent and hydrogen bonds.The abundant-OH and-COOH groups in CS-CA molecules effectively form hydrogen bonds with the-OH groups on the SiO surface,significantly enhancing the interfacial interaction between CS-CA and SiO.The root-like topological structure of CS-CA with a high tolerance alleviates the mechanical stress generated by the volume changes of SiO.More encouragingly,the hydrogen bond action among CS-CA molecules produces a self-healing effect,which is advantageous for repairing damaged electrodes and preserving their structural integrity.As such,the CS-CA/SiO electrode exhibits exceptional cycling performance(963.1 mA h g^(-1)after 400 cycles at 2 A g^(-1))and rate capability(558.9 mA h g^(-1)at 5 A g^(-1)).This innovative,topologically interconnected,root-inspired binder will greatly advance the practical application of long-lasting micron-sized SiO anodes.
基金the financial support from the National Natural Science Foundation of China,Grant Nos.52307249the Natural Science Foundation of Shanghai Province,Nos.23ZR1465900+2 种基金the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission,Nos.23CGA25the Fundamental Research Funds for the Central Universities at Tongji University,Nos.PA2022000668/22120220426the Nanchang Automotive Institute of Intelligence&New Energy of Tongji University,Nos.TPD-TC202211-02。
文摘The imperative pursuit of elevated energy density in lithium primary coin cells(LPCCs)necessitates strategic architectural optimization to align with evolving market demands.A predominant approach involves the systematic replacement of metallic structural support components(MSSCs)to minimize non-active constituent ratios,contingent upon maintaining robust interfacial contact integrity among electrodes,separators,and battery shells.Herein,we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode(UCFxC)to achieve complete MSSCs elimination.The engineered UCFxC demonstrates exceptional areal capacity metrics(249.45 mg cm^(-2),215.77 m Ah cm^(-2)),enabling a 27.8% mass reduction compared with conventional laboratoryassembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity.Notably,single-walled carbon nanotube(SWCNT)-modified UCFxC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50℃.This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems,with practical implications for advancing miniaturized power source technologies.
基金Project supported by the National Natural Science Foundation of China(Nos.U23A20111 and 12372160)。
文摘Radiofrequency ablation(RFA)is a form of minimally invasive procedure that precisely ablates abnormal lesions or hyperplastic tissues through thermal energy generated by the radiofrequency current at the tip electrode of the flexible catheter,which aims to partially or fully restore the function of the corresponding tissues or organs.Accurate prediction and control of thermal fields are crucial for clinical thermal ablation to ensure precise control of the ablation lesion size and prevent excessive burning of healthy tissues.In this study,an axisymmetric analytical model is developed for the electrothermal analysis of RFA in the cambered tissue surface and verified with the finite element analysis(FEA),which incorporates both the thermal field induced by the radiofrequency current and Pennes'biothermal effect.This model utilizes analytically derived electric and thermal fields to accurately predict the increase in the tissue temperature and the time-varying size of ablation lesion in the tissue.Furthermore,the parameters such as the input current density,curvature,and convective heat transfer coefficient of blood have a significant effect on the thermal field and thus the ablation lesion size.This electrothermal analytical model with a large curvature may provide a theoretical foundation and guidance for the future RFA applications on large-curvature biological surfaces,thereby enhancing accuracy,reducing the need for re-ablation,and lowering the costs associated with the design and production of ablation catheters.
基金sponsored by a PhD Scholarship from the School of Chemical Engineering at the University of Birminghamsupported by EU H2020-MSCAIF-2019 project EconCell 898486
文摘Direct formic acid fuel cells are promising energy devices with advantages of low working temperature and high safety in fuel storage and transport.They have been expected to be a future power source for portable electronic devices.The technology has been developed rapidly to overcome the high cost and low power performance that hinder its practical application,which mainly originated from the slow reaction kinetics of the formic acid oxidation and complex mass transfer within the fuel cell electrodes.Here,we provide a comprehensive review of the progress around this technology,in particular for addressing multiscale challenges from catalytic mechanism understanding at the atomic scale,to catalyst design at the nanoscale,electrode structure at the micro scale and design at the millimeter scale,and finally to device fabrication at the meter scale.The gap between the highly active electrocatalysts and the poor electrode performance in practical devices is highlighted.Finally,perspectives and opportunities are proposed to potentially bridge this gap for further development of this technology.
