Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaero...Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaerophobic three dimensional(3D)heterostructured nanowrinkles of bimetallic selenides consisting of crystalline NiSe2 and NiFe2Se4 grown on NiFe alloy(NiSe2/NiFe2Se4@NiFe)prepared by a thermal selenization procedure.In this unique 3D heterostructure,numerous nanowrinkles of NiSe2/NiFe2Se4 hybrid with a thickness of ~100 nm are grown on NiFe alloy in a uniform manner.Profiting by the large active surface area and high electronic conductivity,the superaerophobic NiSe2/NiFe2Se4@NiFe heterostructure exhibits excellent electrocatalytic activity and durability towards OER in alkaline media,outputting the low potentials of 1.53 and 1.54 V to achieve ultra-high current densities of 500 and 1000 mA cm^−2,respectively,which is among the most active Ni/Fe-based selenides,and even superior to the benchmark Ir/C catalyst.The in-situ derived FeOOH and NiOOH species from NiSe2/NiFe2Se4@NiFe are deemed to be efficient active sites for OER.展开更多
To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedr...To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)composites.Among them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly distributed.When assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 cycles.It is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.展开更多
The shell structure design has been recognized as a highly efficient strategy to buffer the severe volume expansion and consecutive pulverization of conversion-type anodes.Nevertheless,construction of a functional she...The shell structure design has been recognized as a highly efficient strategy to buffer the severe volume expansion and consecutive pulverization of conversion-type anodes.Nevertheless,construction of a functional shell with a stabilized structure that meets the demands of both high electronic conductivity and feasible pathways for Na^(+)ions has been a challenge so far.Herein,we design a two-in-one shell configuration for bimetal selenides to achieve fast sodium storage within broadened voltage windows.The hybridized shell,which benefits from the combination of titanium dioxide quantum dots and amorphous carbon,can not only effectively buffer the strain and maintain structural integrity but also allow facile and reversible transport of electrons and Na^(+)uptake for electrode materials during sodiation/desodiation processes,resulting in increased reaction kinetics and diffusion of sodium ions,conferring many benefits to the functionality of conversion-type electrode materials.As a representative material,Ni-CoSe_(2) with such structural engineering shows a reversible capacity of 515 mAh g^(−1)at 0.1 A g^(−1)and a stable capacity of 416 mAh g^(−1)even at 6.4 A g^(−1);more than 80%of the capacity at 0.1 A g^(−1)could be preserved,so that this strategy holds great promise for designing fast-charging conversion-type anodes in the future.展开更多
The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s mead...The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s meadowsweet”in nature,a nanofibrous composite membrane with hierarchical structure was constructed.Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane.The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor,and intelligently integrate multiple heterostructures to enhance dielectric polarization,which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials.Due to the synergistic enhancement of electrospinning-derived carbon nanofiber“stems”,MOF-derived carbon nanosheet“petals”and transition metal selenide nano-particle“stamens”,the CoxSey/NiSe@CNSs@CNFs(CNCC)composite membrane obtains a minimum reflection loss value(RL_(min))of-68.40 dB at 2.6 mm and a maximum effective absorption bandwidth(EAB)of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%.In addition,the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility,water resistance,thermal management,and other multifunctional properties.This work provides unique perspectives for the precise design and rational application of multifunctional fabrics.展开更多
Herein,we focused on the development of the V_(4)C_(3) MXene composite bimetallic selenide heterostruc-ture(V_(4)C_(3)@CuSe_(2)/CoSe_(2))as a cathode material for aluminum batteries.This heterostructure was pre-pared ...Herein,we focused on the development of the V_(4)C_(3) MXene composite bimetallic selenide heterostruc-ture(V_(4)C_(3)@CuSe_(2)/CoSe_(2))as a cathode material for aluminum batteries.This heterostructure was pre-pared through a Lewis melt salt etching and selenization process.By capitalizing on the synergistic effect between the bimetallic selenide and V_(4)C_(3) MXene,V_(4)C_(3)@CuSe_(2)/CoSe_(2) exhibited rapid charge transfer and demonstrated superior discharge specific capacity compared to V_(4)C_(3) composite monometallic selenide.Furthermore,the incorporation of V_(4)C_(3) improved the material's stability during charging/discharging.The initial discharge specific capacity of V_(4)C_(3)@CuSe_(2)/CoSe_(2) reached an impressive 809 mAh g^(-1) at 1 Ag^(-1).Even after nearly 3000 cycles,it retained a substantial capacity of 169.1 mAh g^(-1).Ex-situ XPS analysis confirmed the reversible valence transitions of Cu,Co,and Se elements as the main energy storage reac-tions taking place in the cathode material.Density functional theory analysis provided further insights,revealing that the strong metallic behavior of the heterostructure stemmed from the charge rearrange-ment facilitated by the bimetallic selenide structure and the optimization of the energy level structure.Additionally,the presence of the bimetallic selenide structure significantly improved the adsorption ef-ficiency of[AlCl4]^(-).Overall,this research contributes to the advancement of rechargeable aluminum ion batteries and presents a promising avenue for future developments in composite metal selenide struc-tures and MXene-based materials.展开更多
High areal capacity is one of the critically important points for potassium-ion batteries(PIBs)for practical applications,which relies on high areal-massloading electrodes operating at high reversible capacity.However...High areal capacity is one of the critically important points for potassium-ion batteries(PIBs)for practical applications,which relies on high areal-massloading electrodes operating at high reversible capacity.However,it is remarkably restricted by the mechanical instability and sluggish charge transfer induced by the increased mass loading.To overcome such challenge,we report the rationally designed bimetallic selenides CoSe2/SnSe2 heterostructures confined in hierarchical carbon nanofibers(CSSe@CNFs),which enables the electrodes robust mechanical stability,enhanced electron transport,and reduced ion-diffusion energy barrier for facilitating reaction kinetics.Accordingly,an impressive areal mass loading up to 25.3 mg cm^(−2)was achieved,which endowed a high areal capacity of 7.58 mAh cm^(−2)for such a free-standing electrode.This is stateof-the-art among the PIBs,exceeding that of today’s industry standard(∼3 mAh cm^(−2)for LIBs).Furthermore,it delivered long-term stability over 3700 cycles at high current density(∼2 mA cm^(−2),vs 1 mA cm^(−2)in LIBs).Moreover,the as-constructed full battery achieved a high energy density of 172.8 Wh kg-1 at 0.05 A g^(−1)with a satisfied cycle stability over 2000 cycles at 2 A g^(−1)and high reversibility with Coulombic efficiency of 100%;thus,signifying its bright future toward commercial application for advanced PIBs.展开更多
Given the abundance of potassium resources,potassium-ion batteries are considered a low-cost alternative to lithium-ion types.However,their electrochemical performance remains rather unsatisfactory because potassium i...Given the abundance of potassium resources,potassium-ion batteries are considered a low-cost alternative to lithium-ion types.However,their electrochemical performance remains rather unsatisfactory because potassium ions have sluggish kinetics and large ionic radius.In this study,NiCo_(2)Se_(4)nanotube spheres are synthesized as efficient potassium storage hosts via a facile two-step hydrothermal process.The rationally designed electrode has various ameliorating morphological and functional features,including the following:(i)A hollow structure allows for relief of the volume expansion while offering an excellent electrochemical reac-tivity to accelerate the conversion kinetics;(ii)a high electrical conductivity for enhanced electron transfer;and(iii)myriad vacancies to supply active sites for electrochemical reactions.As such,the electrode delivers an initial reversible capacity of 458.1 mAh g^(−1)and retains 346.6 mAh g^(−1)after 300 cycles at 0.03 A g^(−1).The electrode sustains a high capacity of 101.4 mAh g^(−1)even at a high current density of 5 A g^(−1)and outperforms the majority of state-of-the-art anodes in terms of both cyclic capacity and rate capability,especially at above 1.0 A g^(−1).This study not only proves bimetallic selenides are promising candidates for potassium storage devices but also offers new insight into the rational design of electrode materials for high-rate potassium-ion batteries.展开更多
基金financially supported by the National Natural Science Foundation of China(21922811,51702284,and 21878270)Zhejiang Provincial Natural Science Foundation of China(LR19B060002)the Startup Foundation for Hundred-Talent Program of Zhejiang University.
文摘Cost-effective and stable electrocatalysts with ultra-high current densities for electrochemical oxygen evolution reaction(OER)are critical to the energy crisis and environmental pollution.Herein,we report a superaerophobic three dimensional(3D)heterostructured nanowrinkles of bimetallic selenides consisting of crystalline NiSe2 and NiFe2Se4 grown on NiFe alloy(NiSe2/NiFe2Se4@NiFe)prepared by a thermal selenization procedure.In this unique 3D heterostructure,numerous nanowrinkles of NiSe2/NiFe2Se4 hybrid with a thickness of ~100 nm are grown on NiFe alloy in a uniform manner.Profiting by the large active surface area and high electronic conductivity,the superaerophobic NiSe2/NiFe2Se4@NiFe heterostructure exhibits excellent electrocatalytic activity and durability towards OER in alkaline media,outputting the low potentials of 1.53 and 1.54 V to achieve ultra-high current densities of 500 and 1000 mA cm^−2,respectively,which is among the most active Ni/Fe-based selenides,and even superior to the benchmark Ir/C catalyst.The in-situ derived FeOOH and NiOOH species from NiSe2/NiFe2Se4@NiFe are deemed to be efficient active sites for OER.
基金financially supported by the National Natural Science Foundation of China(No.52102100)the Natural Science Foundation of Jiangsu Province(No.BK20181469)the Guangdong Basic and Applied Basic Research Foundation,China(No.2020A1515110035)。
文摘To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)composites.Among them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly distributed.When assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 cycles.It is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.
基金Fundamental Research Funds for the Central Universities,Grant/Award Numbers:531118010111,531118010633National Natural Science Foundation of China,Grant/Award Numbers:22109041,52103313。
文摘The shell structure design has been recognized as a highly efficient strategy to buffer the severe volume expansion and consecutive pulverization of conversion-type anodes.Nevertheless,construction of a functional shell with a stabilized structure that meets the demands of both high electronic conductivity and feasible pathways for Na^(+)ions has been a challenge so far.Herein,we design a two-in-one shell configuration for bimetal selenides to achieve fast sodium storage within broadened voltage windows.The hybridized shell,which benefits from the combination of titanium dioxide quantum dots and amorphous carbon,can not only effectively buffer the strain and maintain structural integrity but also allow facile and reversible transport of electrons and Na^(+)uptake for electrode materials during sodiation/desodiation processes,resulting in increased reaction kinetics and diffusion of sodium ions,conferring many benefits to the functionality of conversion-type electrode materials.As a representative material,Ni-CoSe_(2) with such structural engineering shows a reversible capacity of 515 mAh g^(−1)at 0.1 A g^(−1)and a stable capacity of 416 mAh g^(−1)even at 6.4 A g^(−1);more than 80%of the capacity at 0.1 A g^(−1)could be preserved,so that this strategy holds great promise for designing fast-charging conversion-type anodes in the future.
基金supported by the National Natural Science Foundation of China(No.51407134,No.52002196)Natural Science Foundation of Shandong Province(No.ZR2019YQ24,No.ZR2020QF084)+2 种基金Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites)Special Financial of Shandong Province(Structural Design of Highefficiency Electromagnetic Wave-absorbing Composite Materials and Construction of Shandong Provincial Talent Teams(No.37000022P990304116449)).
文摘The development of wearable multifunctional electromagnetic protective fabrics with multifunctional,low cost,and high efficiency remains a challenge.Here,inspired by the unique flower branch shape of“Thunberg’s meadowsweet”in nature,a nanofibrous composite membrane with hierarchical structure was constructed.Integrating sophisticated 0D@2D@1D hierarchical structures with multiple heterointerfaces can fully unleash the multifunctional application potential of composite membrane.The targeted induction method was used to precisely regulate the formation site and morphology of the metal–organic framework precursor,and intelligently integrate multiple heterostructures to enhance dielectric polarization,which improves the impedance matching and loss mechanisms of the electromagnetic wave absorbing materials.Due to the synergistic enhancement of electrospinning-derived carbon nanofiber“stems”,MOF-derived carbon nanosheet“petals”and transition metal selenide nano-particle“stamens”,the CoxSey/NiSe@CNSs@CNFs(CNCC)composite membrane obtains a minimum reflection loss value(RL_(min))of-68.40 dB at 2.6 mm and a maximum effective absorption bandwidth(EAB)of 8.88 GHz at a thin thickness of 2.0 mm with a filling amount of only 5 wt%.In addition,the multi-component and hierarchical heterostructure endow the fibrous membrane with excellent flexibility,water resistance,thermal management,and other multifunctional properties.This work provides unique perspectives for the precise design and rational application of multifunctional fabrics.
基金National Natural Science Foundation of China(No.52102233)Science and Technology Project of Hebei Education Department(No.QN2023019).
文摘Herein,we focused on the development of the V_(4)C_(3) MXene composite bimetallic selenide heterostruc-ture(V_(4)C_(3)@CuSe_(2)/CoSe_(2))as a cathode material for aluminum batteries.This heterostructure was pre-pared through a Lewis melt salt etching and selenization process.By capitalizing on the synergistic effect between the bimetallic selenide and V_(4)C_(3) MXene,V_(4)C_(3)@CuSe_(2)/CoSe_(2) exhibited rapid charge transfer and demonstrated superior discharge specific capacity compared to V_(4)C_(3) composite monometallic selenide.Furthermore,the incorporation of V_(4)C_(3) improved the material's stability during charging/discharging.The initial discharge specific capacity of V_(4)C_(3)@CuSe_(2)/CoSe_(2) reached an impressive 809 mAh g^(-1) at 1 Ag^(-1).Even after nearly 3000 cycles,it retained a substantial capacity of 169.1 mAh g^(-1).Ex-situ XPS analysis confirmed the reversible valence transitions of Cu,Co,and Se elements as the main energy storage reac-tions taking place in the cathode material.Density functional theory analysis provided further insights,revealing that the strong metallic behavior of the heterostructure stemmed from the charge rearrange-ment facilitated by the bimetallic selenide structure and the optimization of the energy level structure.Additionally,the presence of the bimetallic selenide structure significantly improved the adsorption ef-ficiency of[AlCl4]^(-).Overall,this research contributes to the advancement of rechargeable aluminum ion batteries and presents a promising avenue for future developments in composite metal selenide struc-tures and MXene-based materials.
基金supported by the National Natural Science Foundation of China(grant nos.52074113,22005091,and 22005092)the Hunan University Outstanding Youth Science Foundation(grant no.531118040319).
文摘High areal capacity is one of the critically important points for potassium-ion batteries(PIBs)for practical applications,which relies on high areal-massloading electrodes operating at high reversible capacity.However,it is remarkably restricted by the mechanical instability and sluggish charge transfer induced by the increased mass loading.To overcome such challenge,we report the rationally designed bimetallic selenides CoSe2/SnSe2 heterostructures confined in hierarchical carbon nanofibers(CSSe@CNFs),which enables the electrodes robust mechanical stability,enhanced electron transport,and reduced ion-diffusion energy barrier for facilitating reaction kinetics.Accordingly,an impressive areal mass loading up to 25.3 mg cm^(−2)was achieved,which endowed a high areal capacity of 7.58 mAh cm^(−2)for such a free-standing electrode.This is stateof-the-art among the PIBs,exceeding that of today’s industry standard(∼3 mAh cm^(−2)for LIBs).Furthermore,it delivered long-term stability over 3700 cycles at high current density(∼2 mA cm^(−2),vs 1 mA cm^(−2)in LIBs).Moreover,the as-constructed full battery achieved a high energy density of 172.8 Wh kg-1 at 0.05 A g^(−1)with a satisfied cycle stability over 2000 cycles at 2 A g^(−1)and high reversibility with Coulombic efficiency of 100%;thus,signifying its bright future toward commercial application for advanced PIBs.
基金supported by the Research Grants Council(GRF project 16208718)the Innovation and Technology Commission(ITF project ITS/001/17)of Hong Kong SARthe National Natural Science Foundation of China(No.52202297).
文摘Given the abundance of potassium resources,potassium-ion batteries are considered a low-cost alternative to lithium-ion types.However,their electrochemical performance remains rather unsatisfactory because potassium ions have sluggish kinetics and large ionic radius.In this study,NiCo_(2)Se_(4)nanotube spheres are synthesized as efficient potassium storage hosts via a facile two-step hydrothermal process.The rationally designed electrode has various ameliorating morphological and functional features,including the following:(i)A hollow structure allows for relief of the volume expansion while offering an excellent electrochemical reac-tivity to accelerate the conversion kinetics;(ii)a high electrical conductivity for enhanced electron transfer;and(iii)myriad vacancies to supply active sites for electrochemical reactions.As such,the electrode delivers an initial reversible capacity of 458.1 mAh g^(−1)and retains 346.6 mAh g^(−1)after 300 cycles at 0.03 A g^(−1).The electrode sustains a high capacity of 101.4 mAh g^(−1)even at a high current density of 5 A g^(−1)and outperforms the majority of state-of-the-art anodes in terms of both cyclic capacity and rate capability,especially at above 1.0 A g^(−1).This study not only proves bimetallic selenides are promising candidates for potassium storage devices but also offers new insight into the rational design of electrode materials for high-rate potassium-ion batteries.