The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalati...The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalation of potassium into/from graphite involve kinetic limitations.The intercalation process of potassium was further confirmed to be governed by both the diffusion of potassium ion in graphite bulk and the phase transition kinetics through the analyses of current-time transient curves with reversible and quasi-reversible equations.The transfer coefficient of the intercalation reaction was calculated to be 0.364 according to the parameters resulting from nonlinear fitting of the current-time transient curves with a quasi-reversible equation.Analysis with scanning electron microscope shows that graphite matrix was severely eroded by intercalation of potassium.展开更多
Fluorescent dye （YOYO-I） intercalated with single DNA molecules were investigated via bindingactivated localization microscopy （BALM） at sub-diffraction limit resolutions. Various dye-to-DNA base pair （bp） ratio...Fluorescent dye （YOYO-I） intercalated with single DNA molecules were investigated via bindingactivated localization microscopy （BALM） at sub-diffraction limit resolutions. Various dye-to-DNA base pair （bp） ratios were imaged using the blinking property of YOYO-1 dye under optimum BALM switching buffer conditions. Individual DNA molecules exhibited regular/irregular intercalating phenomena with respect to dye-to-DNA bp ratio. The acquired images were reconstructed into super-resolution images by applying a Gaussian fit to the centroid of the point spread function. The YOYO-1 intercalated with λ-DNA possessed a non-homogeneous region due to the different binding modes of YOYO-1 with λ-DNA. Each binding mode was imaged at the sub-diffraction limit super-resolution. The distance between homogenously localized intercalating dyes within the DNA molecules was measured to be 34nm （n= 10; dye：DNAbp= 1：100） without photocleavage in 50mmol/L β-mercaptoethylamine buffer. The results were similar to those of the theoretical values without photocleavage in the base pairs of single DNA molecules below the diffraction limit. The results paved the way for an in-depth microscopic analysis of molecular variation with single λ-DNA molecules. With this method, it should be possible to analyze the exact base pair breakdown during various stages of cell apoptosis.展开更多
Superconductivity with transition temperature Tc above 40 K was observed in protonated FeSe(Hy-FeSe)previously with the ionic liquid EMIM-BF4 used in the electrochemical process.However,the real superconducting phase ...Superconductivity with transition temperature Tc above 40 K was observed in protonated FeSe(Hy-FeSe)previously with the ionic liquid EMIM-BF4 used in the electrochemical process.However,the real superconducting phase is not clear until now.And detailed structural,magnetization,and electrical transport measurements are lacking.By using similar protonating technique on FeSe single crystals,we obtain superconducting samples with Tc above 40 K.We show that the obtained superconducting phase is not Hy-FeSe but actually an organic-ion(C6H11N+2 referred to as EMIM^(+))-intercalated phase(EMIM)xFeSe.By using x-ray diffraction technique,two sets of index peaks corresponding to different c-axis lattice constants are detected in the obtained samples,which belong to the newly formed phase of intercalated(EMIM)xFeSe and the residual FeSe,respectively.The superconductivity of(EMIM)xFeSe with Tc of 44.4 K is confirmed by resistivity and magnetic susceptibility measurements.Temperature dependence of resistivity with different applied magnetic fields reveals that the upper critical field Hc2 is quite high,while the irreversibility field Hirr is suppressed quickly with increasing temperature till about 20 K.This indicates that the resultant compound has a high anisotropy with a large spacing between the FeSe layers.展开更多
Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode...Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode,which as a bottleneck limits the fast charge application of DIBs.To maximize interlayer utilization and achieve faster anion diffusion kinetics,a fast and uncrowded anion transport channel must be established.Herein,Li^(+)was pre-intercalated into the graphite paper(GP)cathode to increase the interlayer spacing,and then hosted for the PF_(6)^(-)anion storage.Combined with theoretical calculation,it shows that the local interlayer spacing enlargement and the residual Li^(+)reduce the anion intercalation energy and diffusion barrier,leading to better rate stability.The obtained GP with Li^(+)pre-intercalation(GP-Li)electrode exhibits a discharge capacity of 23.1 m Ah g^(-1) at a high current of 1300 m A g^(-1).This work provides a facile method to efficiently improve the interlayer utilization of graphite cathode at large currents.展开更多
Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(...Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis.展开更多
DNA imaging and visualization techniques are crucial in biological experiments and have also emerged as a powerful method for single-molecule studies.Traditional intercalating dyes(e.g.,SYTOX,EtBr,GelRed)can stain DNA...DNA imaging and visualization techniques are crucial in biological experiments and have also emerged as a powerful method for single-molecule studies.Traditional intercalating dyes(e.g.,SYTOX,EtBr,GelRed)can stain DNA but may alter its structure and mechanical properties,and cause photocleavage.Recently,a novel fluorescent DNA-binding protein(FP-DBP)was introduced,which can stain DNA without sequence preference and without inducing photocleavage.In this study,using a custom-built magnetic tweezers system,we performed DNA stretching,twisting and unzipping experiments to compare the mechanical properties of DNA with and without two kinds of intercalating dyes(SYTOX Orange and GelRed)and mCherry FP-DBP.Our results show that mCherry FP-DBP does not affect DNA structure or mechanics,unlike SYTOX Orange and GelRed,making FP-DBP a promising tool for DNA visualization in single-molecule experiments.展开更多
Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising a...Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.展开更多
The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNT...The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2).展开更多
V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve th...V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.展开更多
Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalyti...Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalytic reaction efficiency and selectivity[1–3].This technique has achieved significant progress in areas such as electrocatalysis,catalytic cracking,and energy conversion,especially in reactions like hydrogen generation,oxygen reduction,nitrogen reduction,and carbon dioxide reduction[4–6].Intercalation catalysis can enhance catalyst activity and selectivity,but challenges remain regarding stability,reusability,and industrial application.Future research will focus on developing new intercalation materials,optimizing catalyst design,and exploring their potential applications in complex environments[7].展开更多
Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs ...Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs their functionality by reducing active sites and obstructing ionic transport.This study presents a facile synthesis approach for nickel-intercalated MXene,designed to enhance surface reactivity,avoid restacking,and achieve improved electrochemical performance.Electrochemical studies revealed that the nickel-MXene hybrid showed better cycling stability,retaining 83.7%of its capacity after 10000 cycles and attaining an energy density of 26 Wh kg^(-1) at a power density of 1872Wkg^(-1).It also exhibited overpotentials of 109 and 482 mV at 10 and 100 mA cm^(-2),respectively,in the hydrogen evolution reaction.To predict the structural and electrical alterations caused by nickel inclusion,as well as to understand the intercalation mechanism,spin-polarized density functional theory calculations were carried out.The theoretical results showed an improved carrier concentration for nickel-MXene.Nickel-MXene possessed superior electronic characteristics and surplus active sites with hexagonal closed-packed(hcp)edge sites,which enhanced electrochemical properties.Our results demonstrate that nickel intercalation prevents the restacking of MXene but also significantly improves their electrochemical characteristics,making them ideal for energy storage and catalytic applications.展开更多
Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chlori...Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chloride oxidation reactions make oxygen evolution reaction(OER)in seawater extremely challenging.Herein,the low-cost and scalable CoFe layered double hydroxides with Cl^(-)intercalation and decorated with Ce(OH)_(3)(named as CoFe-Cl^(-)/Ce(OH)_(3))catalyst is synthesized via rapid electrodeposition under ambient conditions,which is quickly reconstructed into a CeO_(2)decorated and Cl^(-)intercalated CoFeOOH(CoFeOOH-Cl^(-)/CeO_(2))during OER.Theoretical investigation reveals that Cl^(-)intercalation weakens the adsorption ability of Cl^(-)on Co/Fe atoms and hinders unfavorable coupling with chloride,thereby preventing the chlorine corrosion process and enhancing catalytic stability and activity.The CeO_(2)with hard Lewis acidity preferentially binds to OH-with harder Lewis base to ensure the OH-rich microenvironment around catalyst even under high current operating conditions,thus further enhancing stability and improving OER activity.The functionalized CoFe-Cl^(-)/Ce(OH)_(3)delivers 1000 mA cm^(-2)current density at only 329 mV overpotential with excellent stability for 1000 h under alkaline seawater.Electrochemical experiments elucidate the OER catalytic mechanism in which CeO_(2)serves as a co-catalyst for enriching OH-and CoFeOOH-Cl^(-)is the active species.Our work is a substantial step towards achieving massive and sustainable production of hydrogen fuel from immense seawater.展开更多
Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an imp...Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an important parameter for photodetection,the photoresponsive range of 2D OIHPs is usually modulated by finite metal-halide combinations,constraining their further development.The emerging aromatic amine-based alternating-cations-interlayered(A-ACI)hybrid perovskites that exhibit excellent charge transport and additional interlayered structural designability,provide an extra solution for achieving ideal photoresponsive range.Herein,for the first time,the photoresponsive range is successfully broadened in A-ACI hybrid perovskites(NMA)_(4)(FA)_(2)Pb_(3)Br_(12)(2)remolding from(NMA)_(4)(MA)_(2)Pb_(3)Br_(12)(1)(NMA=N-methylbenzylaminium,FA=formamidinium and MA=methylammonium).Particularly,1 and 2adopt an unprecedented configuration that NMA and MA/FA are alternately arranged in the interlayer in a 4:2 manner.Importantly,2 exhibits a narrower bandgap than 1,which can be ascribed to the lowlying conduct band composed of intercalation FAπ*orbitals.Meanwhile,2 possesses a shorter interlayer distance and flatter inorganic skeleton,synergistically facilitating the wider photo-absorption range and further endowing a broadening photoresponsive range(70 nm).This research not only enriches the perovskite family but also provides insights into structure-property relationships.展开更多
Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performa...Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performance Mg cathode materials.Utilizing the common characteristics of various ionic intercalation-type electrodes,we design and train a Crystal Graph Convolutional Neural Network model that can accurately predict electrode voltages for various ions with mean absolute errors(MAE)between0.25 and 0.33 V.By deploying the trained model to stable Mg compounds from Materials Project and GNoME AI dataset,we identify 160 high voltage structures out of 15,308 candidates with voltages above3.0 V and volumetric capacity over 800 mA h/cm^(3).We further train a precise NequIP model to facilitate accurate and rapid simulations of Mg ionic conductivity.From the 160 high voltage structures,the machine learning molecular dynamics simulations have selected 23 cathode materials with both high energy density and high ionic conductivity.This Al-driven workflow dramatically boosts the efficiency and precision of material discovery for multivalent ion batteries,paving the way for advanced Mg battery development.展开更多
Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existen...Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existence form of leached oxygen anions are still controversial.Herein,we selected iron selenite-wrapped hydrated nickel molybdate(denoted as NiMoO/FeSeO)as a pre-catalyst to study the oxyanion effect.It is surprising to find that SeO_(2)-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst surface.The experiment and theoretical calculations show that the existence of SeO_(4)^(2-)intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy barrier.As expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm^(-2)in 1 M KOH.Further,the anion exchange membrane water electrolyzer(AEMWE)consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm^(-2)at 1.70 V and no significant attenuation within 300 h.Our findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.展开更多
MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties en...MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties enables the observation of exotic quantum phenomena such as the quantum anomalous Hall effect,axion insulator states,and Majorana fermions.While the intercalation of Bi_(2)Te_(3)can tune its magnetism,synthesizing pure-phase MnBi_(2)Te_(4)with uniform Bi_(2)Te_(3)intercalation remains challenging,and the fixed interlayer spacing of Bi_(2)Te_(3)limits magnetic coupling tunability.Here,we utilize electrochemical organic molecule intercalation to expand the van der Waals gap of MnBi_(2)Te_(4)and modulate its magnetic properties.Through x-ray diffraction(XRD)characterizations,we confirm that the interlayer spacing of MnBi_(2)Te_(4)is expanded from 13.6°A to 30.5°A and 61.0°A by intercalating quaternary ammonium cations(THA^(+)and CTA^(+)),respectively.The THA-MnBi_(2)Te_(4)exhibits dual complex magnetic behavior,combining AFM ordering with a Neel temperature(T_(N))of 12 K and a small ferromagnetic hysteresis loop at 2 K.The CTA-MnBi_(2)Te_(4)shows robust ferromagnetism,with a Curie point(T_(C))of 15 K,similar to that of the MnBi_(2)Te_(4)monolayer.These results demonstrate that remarkable changes in the magnetic properties of MnBi_(2)Te_(4)can be achieved via electrochemical intercalation,providing new insights into manipulating magnetism in layered magnetic materials.展开更多
The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from ...The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.展开更多
The sandwich heterostructures(SHSs)are novel two-dimensional materials that hold great potential as efficient electro-catalysts.In this work,we computationally designed the BC_(3)/TM/Gr SHSs by intercalating transitio...The sandwich heterostructures(SHSs)are novel two-dimensional materials that hold great potential as efficient electro-catalysts.In this work,we computationally designed the BC_(3)/TM/Gr SHSs by intercalating transition metal atoms into the BC_(3)/graphene heterostructure.After the computational screening,only BC_(3)/Sc/Gr,BC_(3)/Ti/Gr,BC_(3)/Y/Gr and BC_(3)/Zr/Gr are validated as stable SHSs.The electron donation from the intercalated TM atom results in the formation of the negatively charged boron atom(B^(δ)-)and activation of the BC_(3)surface,making the BC_(3)/TM/Gr SHSs highly promising as single-atom catalysts(SACs).The BC_(3)/Sc/Gr and BC_(3)/Y/Gr SHSs exhibit potential in carbon dioxide reduction reaction(CO_(2)RR)and carbon monoxide reduction reaction(CORR)electro-catalysis.Particularly,when BC_(3)/Y/Gr SHS serves as CORR electro-catalyst,the step(∗CHO→∗CHOH)is a potential determining step,with an extremely low limiting potential(UL=-0.10 V).The BC_(3)/Ti/Gr and BC_(3)/Zr/Gr SHSs are suitable as hydrogen evolution reaction(HER)electro-catalysts.Specially,the BC_(3)/Ti/Gr SHS serves as an ideal HER electro-catalyst in acid condition,with close-to-zero adsorption free energy(△GH=0.006 eV)and fairly low overall activation barrier(0.20 eV).By analyzing the electronic properties,the unique adsorption activity of the B^(δ)-on H atom and unsaturated CO_(2)RR intermediates is elucidated as the origin of excellent catalytic activity of BC_(3)/TM/Gr SHSs,which is modulated by the intercalated TM atom.Our work is instructive to rational design of SACs towards energy conversion based on non-metal elements.展开更多
Aqueous iron-ion batteries are regarded as one of the most promising candidates for grid applications owing to their low cost,high theoretical capacity,and excellent stability of iron in aqueous electrolytes.However,t...Aqueous iron-ion batteries are regarded as one of the most promising candidates for grid applications owing to their low cost,high theoretical capacity,and excellent stability of iron in aqueous electrolytes.However,the slow Fe(de)insertion caused by the high polarity of Fe^(2+)makes it difficult to match suitable cathode materials.Herein,defect-rich MoS_(2)with abundant 1T phase is synthesized and successfully applied in aqueous iron-ion batteries.Benefit from abundant active sites generated by the heteroatom incorporation and S vacancy,as well as the highly conductive 1T phase,it can deliver a specific capacity of 123 mAh/g at a current density of 100mA/g,and demonstrates an impressive capacity retention of 88%after 600 cycles at 200mA/g.This work presents a novel pathway for the advancement of cathode materials for aqueous iron-ion batteries.展开更多
With graphite currently leading as the most viable anode for potassium-ion batteries(KIBs),other materials have been left relatively underexamined.Transition metal oxides are among these,with many positive attributes ...With graphite currently leading as the most viable anode for potassium-ion batteries(KIBs),other materials have been left relatively underexamined.Transition metal oxides are among these,with many positive attributes such as synthetic maturity,longterm cycling stability and fast redox kinetics.Therefore,to address this research deficiency we report herein a layered potassium titanium niobate KTiNbO5(KTNO)and its rGO nanocomposite(KTNO/rGO)synthesised via solvothermal methods as a high-performance anode for KIBs.Through effective distribution across the electrically conductive rGO,the electrochemical performance of the KTNO nanoparticles was enhanced.The potassium storage performance of the KTNO/rGO was demonstrated by its first charge capacity of 128.1 mAh g^(−1) and reversible capacity of 97.5 mAh g^(−1) after 500 cycles at 20 mA g^(−1),retaining 76.1%of the initial capacity,with an exceptional rate performance of 54.2 mAh g^(−1)at 1 A g^(−1).Furthermore,to investigate the attributes of KTNO in-situ XRD was performed,indicating a low-strain material.Ex-situ X-ray photoelectron spectra further investigated the mechanism of charge storage,with the titanium showing greater redox reversibility than the niobium.This work suggests this lowstrain nature is a highly advantageous property and well worth regarding KTNO as a promising anode for future high-performance KIBs.展开更多
基金Project(1343-74236000004)supported by the Hunan Province Innovation Foundation for Postgraduate
文摘The kinetics of potassium intercalating into graphite in molten KF at 1 163 K was investigated by means of cyclic voltammetry and chronoamperometry.Cyclic voltammetry results indicate that intercalaltion/deintercalation of potassium into/from graphite involve kinetic limitations.The intercalation process of potassium was further confirmed to be governed by both the diffusion of potassium ion in graphite bulk and the phase transition kinetics through the analyses of current-time transient curves with reversible and quasi-reversible equations.The transfer coefficient of the intercalation reaction was calculated to be 0.364 according to the parameters resulting from nonlinear fitting of the current-time transient curves with a quasi-reversible equation.Analysis with scanning electron microscope shows that graphite matrix was severely eroded by intercalation of potassium.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology(No. 2015R1A2A2A01003839)
文摘Fluorescent dye （YOYO-I） intercalated with single DNA molecules were investigated via bindingactivated localization microscopy （BALM） at sub-diffraction limit resolutions. Various dye-to-DNA base pair （bp） ratios were imaged using the blinking property of YOYO-1 dye under optimum BALM switching buffer conditions. Individual DNA molecules exhibited regular/irregular intercalating phenomena with respect to dye-to-DNA bp ratio. The acquired images were reconstructed into super-resolution images by applying a Gaussian fit to the centroid of the point spread function. The YOYO-1 intercalated with λ-DNA possessed a non-homogeneous region due to the different binding modes of YOYO-1 with λ-DNA. Each binding mode was imaged at the sub-diffraction limit super-resolution. The distance between homogenously localized intercalating dyes within the DNA molecules was measured to be 34nm （n= 10; dye：DNAbp= 1：100） without photocleavage in 50mmol/L β-mercaptoethylamine buffer. The results were similar to those of the theoretical values without photocleavage in the base pairs of single DNA molecules below the diffraction limit. The results paved the way for an in-depth microscopic analysis of molecular variation with single λ-DNA molecules. With this method, it should be possible to analyze the exact base pair breakdown during various stages of cell apoptosis.
基金supported by the National Natural Science Foundation of China(Grant Nos.12061131001 and 52072170)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB25000000)。
文摘Superconductivity with transition temperature Tc above 40 K was observed in protonated FeSe(Hy-FeSe)previously with the ionic liquid EMIM-BF4 used in the electrochemical process.However,the real superconducting phase is not clear until now.And detailed structural,magnetization,and electrical transport measurements are lacking.By using similar protonating technique on FeSe single crystals,we obtain superconducting samples with Tc above 40 K.We show that the obtained superconducting phase is not Hy-FeSe but actually an organic-ion(C6H11N+2 referred to as EMIM^(+))-intercalated phase(EMIM)xFeSe.By using x-ray diffraction technique,two sets of index peaks corresponding to different c-axis lattice constants are detected in the obtained samples,which belong to the newly formed phase of intercalated(EMIM)xFeSe and the residual FeSe,respectively.The superconductivity of(EMIM)xFeSe with Tc of 44.4 K is confirmed by resistivity and magnetic susceptibility measurements.Temperature dependence of resistivity with different applied magnetic fields reveals that the upper critical field Hc2 is quite high,while the irreversibility field Hirr is suppressed quickly with increasing temperature till about 20 K.This indicates that the resultant compound has a high anisotropy with a large spacing between the FeSe layers.
基金financially supported by the National Natural Science Foundation of China(51932003,51872115)the 2020 International Cooperation Project of the Department of Science and Technology of Jilin Province(20200801001GH)the Project supported by State Key Laboratory of Luminescence and Applications(KLA-2020-05)。
文摘Large anions exhibit slow diffusion kinetics in graphite cathode of dual-ion batteries(DIBs);particularly at high current density,it suffers severely from the largely-reduced interlayer utilization of graphite cathode,which as a bottleneck limits the fast charge application of DIBs.To maximize interlayer utilization and achieve faster anion diffusion kinetics,a fast and uncrowded anion transport channel must be established.Herein,Li^(+)was pre-intercalated into the graphite paper(GP)cathode to increase the interlayer spacing,and then hosted for the PF_(6)^(-)anion storage.Combined with theoretical calculation,it shows that the local interlayer spacing enlargement and the residual Li^(+)reduce the anion intercalation energy and diffusion barrier,leading to better rate stability.The obtained GP with Li^(+)pre-intercalation(GP-Li)electrode exhibits a discharge capacity of 23.1 m Ah g^(-1) at a high current of 1300 m A g^(-1).This work provides a facile method to efficiently improve the interlayer utilization of graphite cathode at large currents.
基金support from the National Natural Science Foundation of China(51402100,21905088,21573066 and U19A2017)the Provincial Natural Science Foundation of Hunan(2020JJ5044,2022JJ10006)。
文摘Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis.
基金supported by the National Natural Science Foundation of China(Grant No.32371284)the Open Fund of the State Key Laboratory of Optoelectronic Materials and Technologies,Sun Yatsen University(Grant No.OEMT-2024-ZTS-04)support from the Physical Research Platform in the School of Physics,Sun Yatsen University(Grant No.PRPSP,SYSU).
文摘DNA imaging and visualization techniques are crucial in biological experiments and have also emerged as a powerful method for single-molecule studies.Traditional intercalating dyes(e.g.,SYTOX,EtBr,GelRed)can stain DNA but may alter its structure and mechanical properties,and cause photocleavage.Recently,a novel fluorescent DNA-binding protein(FP-DBP)was introduced,which can stain DNA without sequence preference and without inducing photocleavage.In this study,using a custom-built magnetic tweezers system,we performed DNA stretching,twisting and unzipping experiments to compare the mechanical properties of DNA with and without two kinds of intercalating dyes(SYTOX Orange and GelRed)and mCherry FP-DBP.Our results show that mCherry FP-DBP does not affect DNA structure or mechanics,unlike SYTOX Orange and GelRed,making FP-DBP a promising tool for DNA visualization in single-molecule experiments.
基金supported by the National Natural Science Foundation of China(Grant No.W2412060,22325902 and 52171215)the State Key Laboratory of Clean Energy Utilization(Open Fund Project No.ZJUCEU2023002)。
文摘Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.
基金the financial support from the National Natural Science Foundation of China(No.22178307)China Southern Power Grid(Grant Nos.0470002022030103HX00002-01).
文摘The poor electronic conductivity of metal-organic framework(MOF)materials hinders their direct application in the field of electrocatalysis in fuel cells.Herein,we proposed a strategy of embedding carbon nanotubes(CNTs)during the growth process of MOF crystals,synthesizing a metalloporphyrin-based MOF catalyst TCPPCo-MOF-CNT with a unique CNT-intercalated MOF structure.Physical characterization revealed that the CNTs enhance the overall conductivity while retaining the original characteristics of the MOF and metalloporphyrin.Simultaneously,the insertion of CNTs generated adequate mesopores and created a hierarchical porous structure that enhances mass transfer efficiency.X-ray photoelectron spectroscopic analysis confirmed that the C atom in CNT changed the electron cloud density on the catalytic active center Co,optimizing the electronic structure.Consequently,the E_(1/2) of the TCPPCo-MOF-CNT catalyst under neutral conditions reached 0.77 V(vs.RHE),outperforming the catalyst without CNTs.When the TCPPCo-MOF-CNT was employed as the cathode catalyst in assembling microbial fuel cells(MFCs)with Nafion-117 as the proton exchange membrane,the maxi-mum power density of MFCs reached approximately 500 mW·m^(-2).
文摘V_(2)O_(5)·nH_(2)O has been widely studied for aqueous zinc-ion batteries.The intercalation of inorganic ions has been used as a feasible method to improve the capacity of vanadium pentoxide.To further improve the stability,organic small molecule choline chloride intercalation is used to expand the spacing of the vanadium pentoxide layers and increase the cycling stability.Therefore,we consider the introduction of Sr^(2+)to cointercalate with choline chloride.Here,we synthes-ized vanadium pentoxide cointercalated with Sr^(2+)and choline ions(Ch^(+))via a simple hydrothermal method.The electro-chemical performance shows an enhanced cathode capacitance contribution of Sr&Ch-V_(2)O_(5),with a discharge capacity of 526 mAh·g^(-1)at 0.1 A·g^(-1)and a retention rate of 78.9%after 2000 cycles at 5 A·g^(-1).This work offers a novel strategy for the design of organic‒inorganic hybrid materials for use as cathodes in aqueous zinc-ion batteries.
文摘Intercalation catalysis research involves inserting metal ions,molecules,or ionic liquids into the layered structure of catalysts to adjust their electronic structure and surface properties,thereby optimizing catalytic reaction efficiency and selectivity[1–3].This technique has achieved significant progress in areas such as electrocatalysis,catalytic cracking,and energy conversion,especially in reactions like hydrogen generation,oxygen reduction,nitrogen reduction,and carbon dioxide reduction[4–6].Intercalation catalysis can enhance catalyst activity and selectivity,but challenges remain regarding stability,reusability,and industrial application.Future research will focus on developing new intercalation materials,optimizing catalyst design,and exploring their potential applications in complex environments[7].
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2020R1A6A1A03043435 and NRF-2021R1A2C1008798).
文摘Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs their functionality by reducing active sites and obstructing ionic transport.This study presents a facile synthesis approach for nickel-intercalated MXene,designed to enhance surface reactivity,avoid restacking,and achieve improved electrochemical performance.Electrochemical studies revealed that the nickel-MXene hybrid showed better cycling stability,retaining 83.7%of its capacity after 10000 cycles and attaining an energy density of 26 Wh kg^(-1) at a power density of 1872Wkg^(-1).It also exhibited overpotentials of 109 and 482 mV at 10 and 100 mA cm^(-2),respectively,in the hydrogen evolution reaction.To predict the structural and electrical alterations caused by nickel inclusion,as well as to understand the intercalation mechanism,spin-polarized density functional theory calculations were carried out.The theoretical results showed an improved carrier concentration for nickel-MXene.Nickel-MXene possessed superior electronic characteristics and surplus active sites with hexagonal closed-packed(hcp)edge sites,which enhanced electrochemical properties.Our results demonstrate that nickel intercalation prevents the restacking of MXene but also significantly improves their electrochemical characteristics,making them ideal for energy storage and catalytic applications.
基金financial support from the National Natural Science Foundation of China(52372173,52072034)。
文摘Direct electrolysis of seawater offers a transformative technology for sustainable hydrogen production,circumventing the constraint of freshwater scarcity.However,the serious electrode corrosion and competitive chloride oxidation reactions make oxygen evolution reaction(OER)in seawater extremely challenging.Herein,the low-cost and scalable CoFe layered double hydroxides with Cl^(-)intercalation and decorated with Ce(OH)_(3)(named as CoFe-Cl^(-)/Ce(OH)_(3))catalyst is synthesized via rapid electrodeposition under ambient conditions,which is quickly reconstructed into a CeO_(2)decorated and Cl^(-)intercalated CoFeOOH(CoFeOOH-Cl^(-)/CeO_(2))during OER.Theoretical investigation reveals that Cl^(-)intercalation weakens the adsorption ability of Cl^(-)on Co/Fe atoms and hinders unfavorable coupling with chloride,thereby preventing the chlorine corrosion process and enhancing catalytic stability and activity.The CeO_(2)with hard Lewis acidity preferentially binds to OH-with harder Lewis base to ensure the OH-rich microenvironment around catalyst even under high current operating conditions,thus further enhancing stability and improving OER activity.The functionalized CoFe-Cl^(-)/Ce(OH)_(3)delivers 1000 mA cm^(-2)current density at only 329 mV overpotential with excellent stability for 1000 h under alkaline seawater.Electrochemical experiments elucidate the OER catalytic mechanism in which CeO_(2)serves as a co-catalyst for enriching OH-and CoFeOOH-Cl^(-)is the active species.Our work is a substantial step towards achieving massive and sustainable production of hydrogen fuel from immense seawater.
基金financially supported by the National Natural Science Foundation of China(Nos.22435005,22193042,21921001,52202194,22305105,22201284)the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(No.ZDBSLY-SLH024)。
文摘Two-dimensional(2D)organic-inorganic hybrid perovskites(OIHPs)have been developed as promising candidates for photodetection,owing to their excellent semiconducting features and structural tunability.However,as an important parameter for photodetection,the photoresponsive range of 2D OIHPs is usually modulated by finite metal-halide combinations,constraining their further development.The emerging aromatic amine-based alternating-cations-interlayered(A-ACI)hybrid perovskites that exhibit excellent charge transport and additional interlayered structural designability,provide an extra solution for achieving ideal photoresponsive range.Herein,for the first time,the photoresponsive range is successfully broadened in A-ACI hybrid perovskites(NMA)_(4)(FA)_(2)Pb_(3)Br_(12)(2)remolding from(NMA)_(4)(MA)_(2)Pb_(3)Br_(12)(1)(NMA=N-methylbenzylaminium,FA=formamidinium and MA=methylammonium).Particularly,1 and 2adopt an unprecedented configuration that NMA and MA/FA are alternately arranged in the interlayer in a 4:2 manner.Importantly,2 exhibits a narrower bandgap than 1,which can be ascribed to the lowlying conduct band composed of intercalation FAπ*orbitals.Meanwhile,2 possesses a shorter interlayer distance and flatter inorganic skeleton,synergistically facilitating the wider photo-absorption range and further endowing a broadening photoresponsive range(70 nm).This research not only enriches the perovskite family but also provides insights into structure-property relationships.
基金supported by the National Key R&D Program of China(2022YFA1203400)the National Natural Science Foundation of China(W2441009)。
文摘Magnesium-ion batteries hold promise as future energy storage solutions,yet current Mg cathodes are challenged by low voltage and specific capacity.Herein,we present an AI-driven workflow for discovering high-performance Mg cathode materials.Utilizing the common characteristics of various ionic intercalation-type electrodes,we design and train a Crystal Graph Convolutional Neural Network model that can accurately predict electrode voltages for various ions with mean absolute errors(MAE)between0.25 and 0.33 V.By deploying the trained model to stable Mg compounds from Materials Project and GNoME AI dataset,we identify 160 high voltage structures out of 15,308 candidates with voltages above3.0 V and volumetric capacity over 800 mA h/cm^(3).We further train a precise NequIP model to facilitate accurate and rapid simulations of Mg ionic conductivity.From the 160 high voltage structures,the machine learning molecular dynamics simulations have selected 23 cathode materials with both high energy density and high ionic conductivity.This Al-driven workflow dramatically boosts the efficiency and precision of material discovery for multivalent ion batteries,paving the way for advanced Mg battery development.
基金supported by the National Natural Science Foundation of China(22075196,U22A20418,21878204)the Research Project Supported by Shanxi Scholarship Council of China(2022-050).
文摘Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction(OER)electrocatalysts in the form of oxyhydroxides through electrochemical activation.However,the role and existence form of leached oxygen anions are still controversial.Herein,we selected iron selenite-wrapped hydrated nickel molybdate(denoted as NiMoO/FeSeO)as a pre-catalyst to study the oxyanion effect.It is surprising to find that SeO_(2)-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst surface.The experiment and theoretical calculations show that the existence of SeO_(4)^(2-)intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy barrier.As expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm^(-2)in 1 M KOH.Further,the anion exchange membrane water electrolyzer(AEMWE)consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm^(-2)at 1.70 V and no significant attenuation within 300 h.Our findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1402404 and 2023YFA1406304)the National Natural Science Foundation of China(Grant Nos.92161201,T2221003,12104221,12104220,12274208,12025404,12004174,91961101,T2394473,62274085,12374043,and U2032208)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20230079,BK20243013,and BK20233001)the Fundamental Research Funds for the Central Universities(Grant Nos.020414380192 and 2024300432).
文摘MnBi_(2)Te_(4),which is emerging as an intrinsic antiferromagnetic(AFM)topological insulator,provides a unique platform to investigate the interplay between magnetism and topology.Modulating its magnetic properties enables the observation of exotic quantum phenomena such as the quantum anomalous Hall effect,axion insulator states,and Majorana fermions.While the intercalation of Bi_(2)Te_(3)can tune its magnetism,synthesizing pure-phase MnBi_(2)Te_(4)with uniform Bi_(2)Te_(3)intercalation remains challenging,and the fixed interlayer spacing of Bi_(2)Te_(3)limits magnetic coupling tunability.Here,we utilize electrochemical organic molecule intercalation to expand the van der Waals gap of MnBi_(2)Te_(4)and modulate its magnetic properties.Through x-ray diffraction(XRD)characterizations,we confirm that the interlayer spacing of MnBi_(2)Te_(4)is expanded from 13.6°A to 30.5°A and 61.0°A by intercalating quaternary ammonium cations(THA^(+)and CTA^(+)),respectively.The THA-MnBi_(2)Te_(4)exhibits dual complex magnetic behavior,combining AFM ordering with a Neel temperature(T_(N))of 12 K and a small ferromagnetic hysteresis loop at 2 K.The CTA-MnBi_(2)Te_(4)shows robust ferromagnetism,with a Curie point(T_(C))of 15 K,similar to that of the MnBi_(2)Te_(4)monolayer.These results demonstrate that remarkable changes in the magnetic properties of MnBi_(2)Te_(4)can be achieved via electrochemical intercalation,providing new insights into manipulating magnetism in layered magnetic materials.
基金Project supported by the National Natural Science Foundation of China(Grant No.12274440)the National Key R&D Program of China(Grant No.2022YFA1403903)+1 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33010100)the Fund of the Synergetic Extreme Condition User Facility(SECUF)。
文摘The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.
基金supported by the National Natural Science Foundation of China(No.51972150)the National Key Research Program of China(No.2022YFA1503101)+1 种基金Science and Technology Development Fund,Macao SAR(FDCT No.0024/2022/ITP)the Project of National Center for International Research on Intelligent Nano-Materials and Detection Technology in Environmental Protection,Soochow University(No.SDGH2303).
文摘The sandwich heterostructures(SHSs)are novel two-dimensional materials that hold great potential as efficient electro-catalysts.In this work,we computationally designed the BC_(3)/TM/Gr SHSs by intercalating transition metal atoms into the BC_(3)/graphene heterostructure.After the computational screening,only BC_(3)/Sc/Gr,BC_(3)/Ti/Gr,BC_(3)/Y/Gr and BC_(3)/Zr/Gr are validated as stable SHSs.The electron donation from the intercalated TM atom results in the formation of the negatively charged boron atom(B^(δ)-)and activation of the BC_(3)surface,making the BC_(3)/TM/Gr SHSs highly promising as single-atom catalysts(SACs).The BC_(3)/Sc/Gr and BC_(3)/Y/Gr SHSs exhibit potential in carbon dioxide reduction reaction(CO_(2)RR)and carbon monoxide reduction reaction(CORR)electro-catalysis.Particularly,when BC_(3)/Y/Gr SHS serves as CORR electro-catalyst,the step(∗CHO→∗CHOH)is a potential determining step,with an extremely low limiting potential(UL=-0.10 V).The BC_(3)/Ti/Gr and BC_(3)/Zr/Gr SHSs are suitable as hydrogen evolution reaction(HER)electro-catalysts.Specially,the BC_(3)/Ti/Gr SHS serves as an ideal HER electro-catalyst in acid condition,with close-to-zero adsorption free energy(△GH=0.006 eV)and fairly low overall activation barrier(0.20 eV).By analyzing the electronic properties,the unique adsorption activity of the B^(δ)-on H atom and unsaturated CO_(2)RR intermediates is elucidated as the origin of excellent catalytic activity of BC_(3)/TM/Gr SHSs,which is modulated by the intercalated TM atom.Our work is instructive to rational design of SACs towards energy conversion based on non-metal elements.
基金supported by Shenzhen Fundamental Research Program(No.GXWD20201231165807007-20200802205241003).
文摘Aqueous iron-ion batteries are regarded as one of the most promising candidates for grid applications owing to their low cost,high theoretical capacity,and excellent stability of iron in aqueous electrolytes.However,the slow Fe(de)insertion caused by the high polarity of Fe^(2+)makes it difficult to match suitable cathode materials.Herein,defect-rich MoS_(2)with abundant 1T phase is synthesized and successfully applied in aqueous iron-ion batteries.Benefit from abundant active sites generated by the heteroatom incorporation and S vacancy,as well as the highly conductive 1T phase,it can deliver a specific capacity of 123 mAh/g at a current density of 100mA/g,and demonstrates an impressive capacity retention of 88%after 600 cycles at 200mA/g.This work presents a novel pathway for the advancement of cathode materials for aqueous iron-ion batteries.
基金Y.X.acknowledges the financial support of the Engineering and Physical Sciences Research Council(EP/X000087/1,EP/V000152/1)Leverhulme Trust(RPG-2021-138)Royal Society(IEC\NSFC\223016).
文摘With graphite currently leading as the most viable anode for potassium-ion batteries(KIBs),other materials have been left relatively underexamined.Transition metal oxides are among these,with many positive attributes such as synthetic maturity,longterm cycling stability and fast redox kinetics.Therefore,to address this research deficiency we report herein a layered potassium titanium niobate KTiNbO5(KTNO)and its rGO nanocomposite(KTNO/rGO)synthesised via solvothermal methods as a high-performance anode for KIBs.Through effective distribution across the electrically conductive rGO,the electrochemical performance of the KTNO nanoparticles was enhanced.The potassium storage performance of the KTNO/rGO was demonstrated by its first charge capacity of 128.1 mAh g^(−1) and reversible capacity of 97.5 mAh g^(−1) after 500 cycles at 20 mA g^(−1),retaining 76.1%of the initial capacity,with an exceptional rate performance of 54.2 mAh g^(−1)at 1 A g^(−1).Furthermore,to investigate the attributes of KTNO in-situ XRD was performed,indicating a low-strain material.Ex-situ X-ray photoelectron spectra further investigated the mechanism of charge storage,with the titanium showing greater redox reversibility than the niobium.This work suggests this lowstrain nature is a highly advantageous property and well worth regarding KTNO as a promising anode for future high-performance KIBs.
