As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM c...As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM cells based on conventional silicon-based devices suffer from structural complexity and large footprintlimitations. Here, we demonstrate an ultrafast nonvolatile TCAM cell based on the MoTe2/hBN/multilayergraphene (MLG) van der Waals heterostructure using a top-gated partial floating-gate field-effect transistor(PFGFET) architecture. Based on its ambipolar transport properties, the carrier type in the source/drain andcentral channel regions of the MoTe2 channel can be efficiently tuned by the control gate and top gate, respectively,enabling the reconfigurable operation of the device in either memory or FET mode. When working inthe memory mode, it achieves an ultrafast 60 ns programming/erase speed with a current on-off ratio of ∼105,excellent retention capability, and robust endurance. When serving as a reconfigurable transistor, unipolar p-typeand n-type FETs are obtained by adopting ultrafast 60 ns control-gate voltage pulses with different polarities.The monolithic integration of memory and logic within a single device enables the content-addressable memory(CAM) functionality. Finally, by integrating two PFGFETs in parallel, a TCAM cell with a high current ratioof ∼10^(5) between the match and mismatch states is achieved without requiring additional peripheral circuitry.These results provide a promising route for the design of high-performance TCAM devices for future in-memorycomputing applications.展开更多
The imperative quest for renewable energy sources and advanced energy storage technologies has arisen amidst the escalating perils of climate change and dwindling fossil fuel reserves.In the realm of energy storage te...The imperative quest for renewable energy sources and advanced energy storage technologies has arisen amidst the escalating perils of climate change and dwindling fossil fuel reserves.In the realm of energy storage technologies,asymmetric supercapacitor(ASC)has garnered significant attention owing to its high energy density and power density.In the quest for advanced electrode materials for ASC,the integration of 2D layered heterostructures on hierarchical porous carbon(HPC)substrates has emerged as a promising approach to enhance the electrochemical performance.Herein,a highly innovative hierarchical NiCo LDH/MoS_(2)/HPC heterostructure was successfully synthesized using a simple two-step hydrothermal method for the electrode materials of ASC.Benefiting from the unique hierarchical heterostructure of NiCo LDH/MoS_(2)/HPC composite and the synergistic effect between the components,it reveals an exceptional specific capacitance of 2368 F/g at 0.5 A/g in a three-electrode system,which significantly exceeds that of conventional supercapacitor electrodes.Additionally,the ASC device of NiCo LDH/MoS_(2)/HPC//HPC achieves remarkable specific capacitance of 236 F/g at 0.5 A/g and an impressive energy density of 84Wh/kg at a power density of 400 W/kg,as well as superior cyclic stability.This study not only demonstrates the effectiveness of incorporating MoS_(2) and NiCo LDH into a carbon-based framework for supercapacitor applications but also opens avenues for designing more efficient energy storage devices.展开更多
Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-c...Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-channel field-effect transistors(n-FETs),which poses a significant challenge for monolithic integration.In this study,we investigate the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures through semiconductor technology computer-aided design(TCAD)simulations and theoretical calculations,identifying the conditions necessary to achieve high-density 2DHG.Our simulations demonstrate that increasing the p-Ga N thickness leads to two critical thicknesses determined by surface states and acceptor ionization concentration:one corresponds to the onset of 2DHG formation,and the other to its saturation.Lowering the donor surface state energy level and increasing the acceptor ionization concentration promote 2DHG formation and saturation,although the saturated density remains independent of surface states.Additionally,a higher Al composition enhances intrinsic ionization due to stronger polarization effects,thereby increasing the 2DHG sheet density.Consequently,to achieve high-density 2DHG in p-Ga N/Al Ga N/Ga N heterostructures,it is essential to increase the Al composition,ensure that the p-Ga N thickness exceeds the critical thickness for 2DHG saturation,and maximize the acceptor ionization concentration.This study elucidates the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures and provides valuable guidance for the optimization of p-FET designs.展开更多
Structured design helps to play out the coordination advantage and optimize the performance of electro-chemical reactions.In this work,hierarchical hollow microspheres(Co_(3)S_(4)@NiCo_(2)S_(4)) with unique core-shell...Structured design helps to play out the coordination advantage and optimize the performance of electro-chemical reactions.In this work,hierarchical hollow microspheres(Co_(3)S_(4)@NiCo_(2)S_(4)) with unique core-shell heterostructure were successfully prepared through simple template and solvothermal methods.Thanks to the hollow structure,cross-linked nanowire arrays,and in-situ coating of zeolite imidazole framework(ZIF),Co_(3)S_(4)@NiCo_(2)S_(4) demonstrated excellent electrochemical performance with a specific ca-pacitance of up to 2697.7 F g^(-1)at 1 A g^(-1) and cycling stability of 80.5% after 5000 cycles.The covalent organic framework(COF)derived nano carbon,which had undergone secondary calcination and ZnCl_(2) activation,also exhibited excellent double-layer energy storage performance.Compared to a single calci-nation,the incredible increase in capacitance was up to 208.5 times greater,reaching 291.9 F g^(-1)at 1 A g^(-1)while maintaining ultra-high rate performance(81.0%at 20 A g^(-1)).The hybrid supercapacitor,assem-bled with Co_(3)S_(4)@NiCo_(2)S_(4)as the cathode and COF-derived carbon as the anode,exhibited an extremely high energy density(79.7 Wh kg^(-1)at 693.5 W kg^(-1))and excellent cyclic stability(maintained 79.3%after 10,000 cycles of 20 A g^(-1)),further explaining the reliable and practical characteristics.This work provided reference for the structural optimization of transition metal sulfides and the high-temperature activation of COF-derived carbon.展开更多
The reduction of global carbon emissions and the achievement of carbon neutrality have become the focus of addressing climate change and global warming.Electrochemical CO_(2) reduction(CO_(2)RR),as a technology that c...The reduction of global carbon emissions and the achievement of carbon neutrality have become the focus of addressing climate change and global warming.Electrochemical CO_(2) reduction(CO_(2)RR),as a technology that can efficiently convert CO_(2) into value-added products,is receiving widespread attention.This article reviews the current research status of Cu/metal oxide heterostructures in the field of electrochemical reduction of CO_(2).The review first introduces the importance of electrochemical reduction of CO_(2) and the application potential of Cu/metal oxide heterostructures in this field.Subsequently,a comprehensive discussion is presented on the exploration of various Cu/metal oxide heterostructures and their corresponding structure-performance relationship,with particular emphasis on the catalysts'activity,selectivity,stability and the nature of active sites.Lastly,the review provides an overview of the current research challenges and future development trends in this field.展开更多
Heterogeneous structure and carbon coating are important ways to enhance the reaction kinetics and cycling stability of metal phosphides as anode materials for sodium-ion batteries.Therefore,nitrogen-doped carbon-capp...Heterogeneous structure and carbon coating are important ways to enhance the reaction kinetics and cycling stability of metal phosphides as anode materials for sodium-ion batteries.Therefore,nitrogen-doped carbon-capped triphasic heterostructure Cu_(3)P/Co_(2)P/CoP@NC stands for nitrogen doped carbon nanorods were designed and synthesized through a combination of phosphide and carbonization.Kinetic analyses(cyclic voltammetry,electrochemical impedance spectroscopy,and galvanostatic intermittent titration technique)and density functional theory calculations show that the three-phase heterostructure and carbon layer effectively improve Na adsorption and migration as well as the electrochemical reactivity of the electrode.Based on this,Cu_(3)P/Co_(2)P/CoP@NC demonstrated excellent rate performance(305.9 mAh g^(-1)at 0.3 A g^(-1)and 202.8 mAh g^(-1)even at 10 A g^(-1))and cycling stability(the capacity decay rate is only 0.12%from the 5th to 300th cycle)when it is used for sodium-ion battery anodes.The in situ X-ray diffraction,ex situ X-ray photoelectron spectroscopy,and high-resolution transmission electron microscopy tests showed that Cu_(3)P/Co_(2)P/CoP@NC is based on a conversion reaction mechanism for sodium-ion storage.In addition,the NVP@reduced graphene oxide(rGO)//Cu_(3)P/Co_(2)P/CoP@NC full-cell delivers a high capacity of 210.2 mAh g^(-1)after 50 cycles at 0.3 A g^(-1).This work can provide a reference for the design of high-performance sodium electrode anode materials.展开更多
Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is...Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is explored by filling CNTs with one-dimensional(1D)-TM_(6)Te_(6) nanowires to form TM_(6)Te_(6)@CNT-(16,0) 1D van der Waals heterostructures(1D-vd WHs). The systematic first-principles studies on the electronic properties of 1D-vd WHs show that N-type doping CNTs can be formed by charge transfer from TM_(6)Te_(6) nanowires to CNTs, without introducing additional carrier scattering.Particularly, contribution from both T M(e.g., Sc and Y) and Te atoms strengthens the charge transfer. The outside CNTs further confine the dispersion of Te-p orbitals in nanowires that deforms the C-π states at the bottom of the conduction band to quasi sp^(3) hybridization. Our study provides an inner doping strategy that can effectively confine the charge polarity of CNTs and further broaden its applications in some novel nano-devices.展开更多
The research on two-dimensional(2D)magnetic materials and their heterostructures is crucial in fields like spintronics,materials science,and condensed matter physics.This study uses terahertz(THz)time-domain spectrosc...The research on two-dimensional(2D)magnetic materials and their heterostructures is crucial in fields like spintronics,materials science,and condensed matter physics.This study uses terahertz(THz)time-domain spectroscopy to investigate ultrafast electron transport properties in both van der Waals Fe_(4)GeTe_(2)films and Bi_(2)Te_(3)/Fe_(4)GeTe_(2)ferromagnetic/topological heterostructures.Our results show that these heterostructures exhibit effective THz electromagnetic shielding.The complex conductivity spectra of Fe_(4)GeTe_(2)films and Bi_(2)Te_(3)/Fe_(4)GeTe_(2)heterostructures with varying Fe_(4)GeTe_(2)thicknesses are analyzed using the Drude-Smith model.We quantitatively examine how Fe_(4)GeTe_(2)layer thickness affects the direct current conductivity,plasma frequency,carrier momentum scattering time,and back-scattering coefficient.As the number of Fe_(4)GeTe_(2)layers increases,intra-layer back-scattering events for charge carriers become more frequent.This work provides THz frequency spectra for both Fe_(4)GeTe_(2)and Bi_(2)Te_(3)/Fe_(4)GeTe_(2),aiding in the design and optimization of THz modulators and detectors.展开更多
In this work,we studied the persistent photoconductivity(PPC)spectra in single HgTe/CdHgTe quantum wells with different growth parameters and different types of dark conductivity.The studies were performed in a wide r...In this work,we studied the persistent photoconductivity(PPC)spectra in single HgTe/CdHgTe quantum wells with different growth parameters and different types of dark conductivity.The studies were performed in a wide radiation quantum energy range of 0.62–3.1 eV both at T=4.2 K and at T=77 K.Common features of the PPC spectra for all structures were revealed,and their relation to the presence of a CdTe cap layer in all structures and the appropriate cadmium fraction in the CdHgTe barrier layers was shown.One of the features was associated with the presence of a deep level in the CdTe layer.In addition,the oscillatory behavior of the PPC spectra in the region from 0.8–1.1 eV to 1.2–1.5 eV was observed.It is associated with the cascade emission of longitudinal optical phonons in CdHgTe barrier.展开更多
Nanostructure engineering and composition rationalization are crucial for materials to become candidates for high-performance supercapacitor.Herein,a novel core-shell heterostructured electrode,combining CoS hollow na...Nanostructure engineering and composition rationalization are crucial for materials to become candidates for high-performance supercapacitor.Herein,a novel core-shell heterostructured electrode,combining CoS hollow nanorods with NiCoMn-layered double hydroxides(LDH)ternary metal nanosheets,were prepared on carbon cloth by reasonably controlled vulcanization and electrodeposition.By optimizing electrodeposition conditions,the material's structure and properties can be fine-tuned.The enhanced capacitance of the optimized carbon cloth(CC)@CoS/NiCoMn-LDH-300 electrode(4256.0 F g^(-1))lies in the open space provided by CoS and the establishment of a new charge transfer channel across the interfaces of CC@CoS/NiCoMn-LDH-300 nanosheets.This is further demonstrated by Density functional theory(DFT)simulations based on OHadsorption energy,which produces faster redox charge kinetics and significantly enhances the electrode's energy storage capacity.The hybrid supercapacitor,integrating the optimized CC@CoS/NiCoMn-LDH-300 electrode with active carbon,demonstrates the highest energy density of 86 Wh kg^(-1)(under the power density of 850 W kg^(-1))and the long cycle stability of 89.7%.This study aims to go beyond simple binary LDH by constructing a ternary LDH with a hierarchical core-shell heterostructure to provide an effective and feasible new concept for high-performance supercapacitor electrode materials via rational structure design.展开更多
Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-i...Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-intercalation of Mg^(2+)in the cathode limit their commercial application.This study presents a novel interface-coupled V_(2)CT_(x)@VS_(4)heterostructure through a one-step hydrothermal process.In this architecture,V_(2)CT_(x)and VS_(4)can mutually support their structural framework,which effectively prevents the structural collapse of V_(2)CT_(x)MXene and the aggregation of VS_(4).Crucially,interfacial coupling between V_(2)CT_(x)and VS_(4)induces strong V-S bonds,substantially enhancing structural stability.Benefiting from these advantages,the heterostructure exhibits high specific capacity(226 mAh g^(-1)at 100 mA g^(-1))and excellent long-cycle stability(89% capacity retention after 1000 cycles at 500 mA g^(-1)).Furthermore,the Mg^(2+)storage mechanism in the V_(2)CT_(x)@VS_(4)composite was elucidated through a series of ex-situ characterizations.This work provides a feasible strategy for designing V_(2)CT_(x)MXene-based cathodes with high capacity and extended cyclability for RMBs.展开更多
In this work,the synthesis of uniform zeolitic imidazolate framework-coated Mo-glycerate spheres and their subsequent conversion into hierarchical architecture containing bimetallic selenides heterostructures and nitr...In this work,the synthesis of uniform zeolitic imidazolate framework-coated Mo-glycerate spheres and their subsequent conversion into hierarchical architecture containing bimetallic selenides heterostructures and nitrogen-doped carbon shell are reported.Selenization temperature plays a significant role in determining the phases,morphology,and lithium-ion storage performance of the composite.Notably,the optimal electrode demonstrates an ultrahigh reversible capacity of 1298.2 mAh/g after 100 cycles at 0.2 A/g and an outstanding rate capability with the capacity still maintained 505.7 mAh/g after 300 cycles at 1.0 A/g,surpassing the calculated theoretical capacity according to individual component and most of the reported MoSe@C-or ZnSe@C-based anodes.Furthermore,ex-situ X-ray diffraction patterns reveal the combined conversion and alloying reaction mechanisms of the composite.展开更多
Surface adsorption plays a crucial role in various natural and industrial processes,particularly in the field of energy storage.The adsorption of sodium atoms on 2D layered materials can significantly impact their per...Surface adsorption plays a crucial role in various natural and industrial processes,particularly in the field of energy storage.The adsorption of sodium atoms on 2D layered materials can significantly impact their performance as carriers and electrodes in ion batteries.While it is commonly acknowledged that pristine graphene is not favorable for sodium ion adsorption,the suitability of other 2D materials with similar honeycomb symmetry remains unclear.In this study,we employ systematic first-principles calculations to explore interlayer interactions and electron transfer effects on sodium adsorption on 2D van der Waals(vdW)heterostructures(HTSs)surfaces.Our results demonstrate that sodium adsorption is energetically favorable on these substrates.Moreover,we find that the adsorption strength can be effectively tuned by manipulation of the electron accumulation or depletion of the layer directly interacting with the sodium atom.By stacking these layered materials with different electron abundancy to form vd W HTSs,the charge density of the substrate becomes tunable through interlayer charge transfer.In these vdW HTSs,the adsorption behavior of sodium is primarily controlled by the absorption layer and exhibits a linear correlation with its pz-band center.Additionally,we identify linear correlations between the sodium adsorption energies,the electron loss of the sodium atom,the interlayer charge transfer,and the heights of the adsorbed sodium atom.These discoveries underscore the impact of interlayer electron transfer and interactions on sodium ion adsorption on 2D vd W HTSs and providing new insights into material design for alkali atom adsorption.展开更多
The heterostructures incorporated with two or more distinctive two-dimensional(2D)materials have attracted great attention be-cause they could give rise to enhanced prop-erty in comparison with their individual counte...The heterostructures incorporated with two or more distinctive two-dimensional(2D)materials have attracted great attention be-cause they could give rise to enhanced prop-erty in comparison with their individual counterparts.Here,a water-assisted two-step rapid physical vapor deposition(rPVD)method was explored and used to synthesize Bi_(2)Te_(3)-Sb_(2)Te_(3)lateral het-erostructures(LHS)successfully.The Bi_(2)Te_(3)-Sb_(2)Te_(3)LHS is in nearly uniform size,and grows along three particular orientations with the intersection angles of 120°.Inter-estingly,we found that the water molecules play a significant role in determining the growth orientation,namely whether it will grow along the vertical or lateral direction in 2D structure.Hence,a growth mechanism of LHS based on the water-assisted two-step rPVD was present,which can be used as a general strategy and extended to the growth of other 2D heterostruc-tures or homostructures,such as SnS-SnSe LHS and SnS-SnS lateral homostructures.Fur-thermore,the second-harmonic generation intensity of the Bi_(2)Te_(3)-Sb_(2)Te_(3)LHS is much stronger than that of the Bi_(2)Te_(3)/Sb_(2)Te_(3)vertical heterostructures(VHS).This work opens a new approach for the synthesis of water-assisted lateral 2D heterostructures or homostruc-tures and offers a new method to enhance the second-harmonic generation properties of topo-logical insulating materials.展开更多
Rational developing high-performance and economically efficient dual-functional oxygen electrocatalysts to drive the lumberly reactivity rates of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)in Zn-a...Rational developing high-performance and economically efficient dual-functional oxygen electrocatalysts to drive the lumberly reactivity rates of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)in Zn-air batteries is highly attractive,yet remains conceptually challenging.Herein,Ni/MnO heterostructure nanosheets and nanoparticles firmly anchored onto the N-doped carbon nanofibers(noted as Ni/MnO@N-C NS/NFs)for efficient bifunctional ORR/OER electrocatalysis are designed and realized through a facile electrospinning-pyrolysis-etching strategy.The epitaxial in situ grown Ni/MnO with enriched oxygen vacancies stimulated the charge redistribution in their coupling regions,which effectively optimizes the adsorption/desorption of O-related intermediates in ORR/OER.Benefiting from the Ni/MnO heterostructure moieties and the unique two-dimensional/one-dimensional(2D/1D)superstructure of carbon support with abundantly dispersive active species,the resultant Ni/MnO@N-C NS/NFs deliver robust ORR activity and OER property(an overpotential of 306 mV to obtain 10 mA·cm^(-2))with a smaller potential gap(ΔE=0.77 V)in alkaline electrolyte.More significantly,practical zinc-air battery building with Ni/MnO@N-C NS/NFs delivers a higher open circuit voltage,excellent output power density,and prominent durability with stable charging and discharging cycle life.The present work demonstrates a crucial understanding of building advanced heterostructure electrocatalysts with enriched oxygen vacancies for metal-air batteries application.展开更多
Interlayer interactions in bilayer or multilayer electron systems have been studied extensively,and many exotic physical phenomena have been revealed.However,systematic investigations of the impact of interlayer inter...Interlayer interactions in bilayer or multilayer electron systems have been studied extensively,and many exotic physical phenomena have been revealed.However,systematic investigations of the impact of interlayer interactions on magnonic physics are very few.Here,we use a van derWaals(vdW)honeycomb heterostructure as a platform to investigate the modulation of magnon properties in honeycomb AA-and AB-stacking heterostructures with ferromagnetic and antiferromagnetic interlayer interactions,including topological phases and thermal Hall conductivity.Our results reveal that interlayer interactions play a crucial role in modulating the magnonic topology and Hall transport properties of magnetic heterostructures,with potential for experimental realization.展开更多
Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride he...Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.展开更多
Extensive first-principles calculations have been performed to examine the electrochemical properties of Na-ion-intercalatable heterostructures formed by transitional metal dichalcogenides(MS_(2),where M=Ti,V,Nb and M...Extensive first-principles calculations have been performed to examine the electrochemical properties of Na-ion-intercalatable heterostructures formed by transitional metal dichalcogenides(MS_(2),where M=Ti,V,Nb and Mo)and blue phosphorus(BlueP),which have been reported as potential anode materials for rechargeable sodium-ion batteries.Upon formation of heterostructures,much improved structural stabilities have observed compared with the pristine MS_(2) and BlueP.Metallic T-TiS_(2),T-MoS_(2),H(T)-VS_(2) and H(T)-NbS_(2) would retain the conductive character after formation of heterostructures with BlueP,however,HTiS_(2)/BlueP and H-MoS_(2)/BlueP would undergo a semiconductor to metallic transition accompanied by Na intercalation.Moreover,the presence of relatively low diffusion barriers ranging from 0.04 eV to 0.08 eV,coupled with the suitable average open-circuit voltage spanning from 0.12 eV to 0.89 eV,guarantee exceptional charge-discharge rates and ensure the safety of battery performance.Among these heterostructures,H(T)-NbS_(2)/BlueP and T-TiS_(2)/BlueP exhibit best Na adsorption ability of up to 4 layers,corresponding to theoretical capacities of 570.2 and 746.7 mAh/g,respectively.These encouraging properties indicate that T-TiS_(2)/BlueP and H(T)-NbS_(2)/BlueP could serve as suitable anode materials for high-performance sodiumion batteries.展开更多
Direct borohydride hydrogen peroxide fuel cells(DBHPFCs)are emerging as a transformative technology for sustainable energy conversion.Despite their potential,their efficiency is largely hindered by the limitations of ...Direct borohydride hydrogen peroxide fuel cells(DBHPFCs)are emerging as a transformative technology for sustainable energy conversion.Despite their potential,their efficiency is largely hindered by the limitations of the anode catalyst.In response to this challenge,we have developed a novel series of Co-based heterojunction metal-organic framework(MOF)derivatives,supported on reduced graphene oxide(rGO)-modified nickel foam(NF),to enhance borohydride electrooxidation performance.Our synthesis involves the thermal transformation of a ZIF67-Co(OH)_(2)-rGO/NF precursor within a controlled temperature between 300 and 750℃,yielding distinct phase heterostructures and pristine Co and CoO,verified by X-ray diffraction(XRD)and transmission electron microscopy(TEM)analyses.Additionally,the Ultraviolet photoelectron spectroscopy and theoretical calculation result further validate the formation of the heterojunction and direction of electron transfer along the interface as well as the BH_(4)^(-)adsorption behavior across the heterointerface.Notably,the catalyst annealed at 600℃,designated Co-CoO@C-rGO/NF-600,exhibits an exceptional oxidation current density of 2.5 A cm^(-2)at 0 V vs.Ag/AgCl in an electrolyte containing 2 mol L^(-1)NaOH and 0.4 mol L^(-1)NaBH_(4)Furthermore,the Co-CoO@C-rGO/NF-600 catalyst demonstrates remarkable performance as the anode catalyst in a DBHPFC assembly,achieving a peak power density of 385.73 mW cm^(-2)and demonstrating the enduring operational stability.The superior electrocatalytic performance is primarily attributed to the synergistic effects of Co-CoO nanoparticles rich in active heterointerfaces and the superior electron mobility afforded by the rGO scaffold.These results not only deepen our understanding of anode catalyst design for DBHPFCs but also pave the way for breakthroughs in electrocatalytic technologies,driving forward the quest for sustainable energy solutions.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
基金supported by the National Key Research&Development Projects of China(Grant No.2022YFA1204100)National Natural Science Foundation of China(Grant No.62488201)+1 种基金CAS Project for Young Scientists in Basic Research(YSBR-003)the Innovation Program of Quantum Science and Technology(2021ZD0302700)。
文摘As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM cells based on conventional silicon-based devices suffer from structural complexity and large footprintlimitations. Here, we demonstrate an ultrafast nonvolatile TCAM cell based on the MoTe2/hBN/multilayergraphene (MLG) van der Waals heterostructure using a top-gated partial floating-gate field-effect transistor(PFGFET) architecture. Based on its ambipolar transport properties, the carrier type in the source/drain andcentral channel regions of the MoTe2 channel can be efficiently tuned by the control gate and top gate, respectively,enabling the reconfigurable operation of the device in either memory or FET mode. When working inthe memory mode, it achieves an ultrafast 60 ns programming/erase speed with a current on-off ratio of ∼105,excellent retention capability, and robust endurance. When serving as a reconfigurable transistor, unipolar p-typeand n-type FETs are obtained by adopting ultrafast 60 ns control-gate voltage pulses with different polarities.The monolithic integration of memory and logic within a single device enables the content-addressable memory(CAM) functionality. Finally, by integrating two PFGFETs in parallel, a TCAM cell with a high current ratioof ∼10^(5) between the match and mismatch states is achieved without requiring additional peripheral circuitry.These results provide a promising route for the design of high-performance TCAM devices for future in-memorycomputing applications.
基金supported by the National Key Research and Development Program of China(No.2021YFB3801200)the National Natural Science Foundation of China(Nos.22278051,22178044,and 22308043)the Science and Technology Innovation foundation of CNPC(No.2022DQ02–0608).
文摘The imperative quest for renewable energy sources and advanced energy storage technologies has arisen amidst the escalating perils of climate change and dwindling fossil fuel reserves.In the realm of energy storage technologies,asymmetric supercapacitor(ASC)has garnered significant attention owing to its high energy density and power density.In the quest for advanced electrode materials for ASC,the integration of 2D layered heterostructures on hierarchical porous carbon(HPC)substrates has emerged as a promising approach to enhance the electrochemical performance.Herein,a highly innovative hierarchical NiCo LDH/MoS_(2)/HPC heterostructure was successfully synthesized using a simple two-step hydrothermal method for the electrode materials of ASC.Benefiting from the unique hierarchical heterostructure of NiCo LDH/MoS_(2)/HPC composite and the synergistic effect between the components,it reveals an exceptional specific capacitance of 2368 F/g at 0.5 A/g in a three-electrode system,which significantly exceeds that of conventional supercapacitor electrodes.Additionally,the ASC device of NiCo LDH/MoS_(2)/HPC//HPC achieves remarkable specific capacitance of 236 F/g at 0.5 A/g and an impressive energy density of 84Wh/kg at a power density of 400 W/kg,as well as superior cyclic stability.This study not only demonstrates the effectiveness of incorporating MoS_(2) and NiCo LDH into a carbon-based framework for supercapacitor applications but also opens avenues for designing more efficient energy storage devices.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFB3604203)the Key Research and Development Program of Guangdong Province,China(Grant No.2024B0101060002)the Key Research and Development Program of Shenzhen City,China(Grant No.JCYJ20241202130036043)。
文摘Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-channel field-effect transistors(n-FETs),which poses a significant challenge for monolithic integration.In this study,we investigate the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures through semiconductor technology computer-aided design(TCAD)simulations and theoretical calculations,identifying the conditions necessary to achieve high-density 2DHG.Our simulations demonstrate that increasing the p-Ga N thickness leads to two critical thicknesses determined by surface states and acceptor ionization concentration:one corresponds to the onset of 2DHG formation,and the other to its saturation.Lowering the donor surface state energy level and increasing the acceptor ionization concentration promote 2DHG formation and saturation,although the saturated density remains independent of surface states.Additionally,a higher Al composition enhances intrinsic ionization due to stronger polarization effects,thereby increasing the 2DHG sheet density.Consequently,to achieve high-density 2DHG in p-Ga N/Al Ga N/Ga N heterostructures,it is essential to increase the Al composition,ensure that the p-Ga N thickness exceeds the critical thickness for 2DHG saturation,and maximize the acceptor ionization concentration.This study elucidates the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures and provides valuable guidance for the optimization of p-FET designs.
基金the College Students Innovative Practice Fund of Jiangsu University Industrial Center(ZXJG2023047)for funding this research.
文摘Structured design helps to play out the coordination advantage and optimize the performance of electro-chemical reactions.In this work,hierarchical hollow microspheres(Co_(3)S_(4)@NiCo_(2)S_(4)) with unique core-shell heterostructure were successfully prepared through simple template and solvothermal methods.Thanks to the hollow structure,cross-linked nanowire arrays,and in-situ coating of zeolite imidazole framework(ZIF),Co_(3)S_(4)@NiCo_(2)S_(4) demonstrated excellent electrochemical performance with a specific ca-pacitance of up to 2697.7 F g^(-1)at 1 A g^(-1) and cycling stability of 80.5% after 5000 cycles.The covalent organic framework(COF)derived nano carbon,which had undergone secondary calcination and ZnCl_(2) activation,also exhibited excellent double-layer energy storage performance.Compared to a single calci-nation,the incredible increase in capacitance was up to 208.5 times greater,reaching 291.9 F g^(-1)at 1 A g^(-1)while maintaining ultra-high rate performance(81.0%at 20 A g^(-1)).The hybrid supercapacitor,assem-bled with Co_(3)S_(4)@NiCo_(2)S_(4)as the cathode and COF-derived carbon as the anode,exhibited an extremely high energy density(79.7 Wh kg^(-1)at 693.5 W kg^(-1))and excellent cyclic stability(maintained 79.3%after 10,000 cycles of 20 A g^(-1)),further explaining the reliable and practical characteristics.This work provided reference for the structural optimization of transition metal sulfides and the high-temperature activation of COF-derived carbon.
基金supported by the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_0120)the National Natural Science Foundation of China(Nos.22275088 and 52101260)+3 种基金the Project of Shuangchuang Scholar of Jiangsu Province(No.JSSCBS20210212)the Fundamental Research Funds for the Central Universities(No.30921011203)the Start-Up Grant(No.AE89991/340)from Nanjing University of Science and Technology,the Foundation of Jiangsu Educational Committee(No.22KJB310008)the Senior Talent Program of Jiangsu University(No.20JDG073).
文摘The reduction of global carbon emissions and the achievement of carbon neutrality have become the focus of addressing climate change and global warming.Electrochemical CO_(2) reduction(CO_(2)RR),as a technology that can efficiently convert CO_(2) into value-added products,is receiving widespread attention.This article reviews the current research status of Cu/metal oxide heterostructures in the field of electrochemical reduction of CO_(2).The review first introduces the importance of electrochemical reduction of CO_(2) and the application potential of Cu/metal oxide heterostructures in this field.Subsequently,a comprehensive discussion is presented on the exploration of various Cu/metal oxide heterostructures and their corresponding structure-performance relationship,with particular emphasis on the catalysts'activity,selectivity,stability and the nature of active sites.Lastly,the review provides an overview of the current research challenges and future development trends in this field.
基金supported by the National Natural Science Foundation of China (No. 22305210, 52371238 to C. D.)the Shandong Provincial Natural Science Foundation (No. ZR2020QB108)+1 种基金the Graduate Innovation Foundation of Yantai University (GIFYTU)the Shandong Laboratory of Advanced Materials and Green Manufacturing (Yantai, AMGM2024A01)
文摘Heterogeneous structure and carbon coating are important ways to enhance the reaction kinetics and cycling stability of metal phosphides as anode materials for sodium-ion batteries.Therefore,nitrogen-doped carbon-capped triphasic heterostructure Cu_(3)P/Co_(2)P/CoP@NC stands for nitrogen doped carbon nanorods were designed and synthesized through a combination of phosphide and carbonization.Kinetic analyses(cyclic voltammetry,electrochemical impedance spectroscopy,and galvanostatic intermittent titration technique)and density functional theory calculations show that the three-phase heterostructure and carbon layer effectively improve Na adsorption and migration as well as the electrochemical reactivity of the electrode.Based on this,Cu_(3)P/Co_(2)P/CoP@NC demonstrated excellent rate performance(305.9 mAh g^(-1)at 0.3 A g^(-1)and 202.8 mAh g^(-1)even at 10 A g^(-1))and cycling stability(the capacity decay rate is only 0.12%from the 5th to 300th cycle)when it is used for sodium-ion battery anodes.The in situ X-ray diffraction,ex situ X-ray photoelectron spectroscopy,and high-resolution transmission electron microscopy tests showed that Cu_(3)P/Co_(2)P/CoP@NC is based on a conversion reaction mechanism for sodium-ion storage.In addition,the NVP@reduced graphene oxide(rGO)//Cu_(3)P/Co_(2)P/CoP@NC full-cell delivers a high capacity of 210.2 mAh g^(-1)after 50 cycles at 0.3 A g^(-1).This work can provide a reference for the design of high-performance sodium electrode anode materials.
基金Project supported by the National Natural Science Foundation of China (Grant No. 92477205)。
文摘Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is explored by filling CNTs with one-dimensional(1D)-TM_(6)Te_(6) nanowires to form TM_(6)Te_(6)@CNT-(16,0) 1D van der Waals heterostructures(1D-vd WHs). The systematic first-principles studies on the electronic properties of 1D-vd WHs show that N-type doping CNTs can be formed by charge transfer from TM_(6)Te_(6) nanowires to CNTs, without introducing additional carrier scattering.Particularly, contribution from both T M(e.g., Sc and Y) and Te atoms strengthens the charge transfer. The outside CNTs further confine the dispersion of Te-p orbitals in nanowires that deforms the C-π states at the bottom of the conduction band to quasi sp^(3) hybridization. Our study provides an inner doping strategy that can effectively confine the charge polarity of CNTs and further broaden its applications in some novel nano-devices.
基金Project supported by the National Key Research and Development Program of China(Grant No.2023YFF0719200)the National Natural Science Foundation of China(Grant Nos.62322115,U24A20226,61988102,and 62435010)+1 种基金the 111 Project(Grant No.D18014)the Science and Technology Commission of Shanghai Municipality(Grant Nos.22JC1400200 and 21S31907400)。
文摘The research on two-dimensional(2D)magnetic materials and their heterostructures is crucial in fields like spintronics,materials science,and condensed matter physics.This study uses terahertz(THz)time-domain spectroscopy to investigate ultrafast electron transport properties in both van der Waals Fe_(4)GeTe_(2)films and Bi_(2)Te_(3)/Fe_(4)GeTe_(2)ferromagnetic/topological heterostructures.Our results show that these heterostructures exhibit effective THz electromagnetic shielding.The complex conductivity spectra of Fe_(4)GeTe_(2)films and Bi_(2)Te_(3)/Fe_(4)GeTe_(2)heterostructures with varying Fe_(4)GeTe_(2)thicknesses are analyzed using the Drude-Smith model.We quantitatively examine how Fe_(4)GeTe_(2)layer thickness affects the direct current conductivity,plasma frequency,carrier momentum scattering time,and back-scattering coefficient.As the number of Fe_(4)GeTe_(2)layers increases,intra-layer back-scattering events for charge carriers become more frequent.This work provides THz frequency spectra for both Fe_(4)GeTe_(2)and Bi_(2)Te_(3)/Fe_(4)GeTe_(2),aiding in the design and optimization of THz modulators and detectors.
基金supported by the Russian Science Foundation (Grant No. 22-12-00298)supported by the Center of Excellence "Center of Photonics" funded by the Ministry of Science and Higher Education of the Russian Federation, Contract #075-15-2022-316the Theoretical Physics and Mathematics Advancement Foundation "BASIS" scholarship for the support.
文摘In this work,we studied the persistent photoconductivity(PPC)spectra in single HgTe/CdHgTe quantum wells with different growth parameters and different types of dark conductivity.The studies were performed in a wide radiation quantum energy range of 0.62–3.1 eV both at T=4.2 K and at T=77 K.Common features of the PPC spectra for all structures were revealed,and their relation to the presence of a CdTe cap layer in all structures and the appropriate cadmium fraction in the CdHgTe barrier layers was shown.One of the features was associated with the presence of a deep level in the CdTe layer.In addition,the oscillatory behavior of the PPC spectra in the region from 0.8–1.1 eV to 1.2–1.5 eV was observed.It is associated with the cascade emission of longitudinal optical phonons in CdHgTe barrier.
基金supported by the National Natural Science Foundation of China(52203147)the Zhejiang Provincial Natural Science Foundation of China(LQ22B010006)+2 种基金the significant science and technology projects of LongMen Laboratory in Henan Province(231100221100)the significant science and technology projects of LongMen Laboratory in Henan Province(231100220100)the Key research and development program of Henan province(231111222200).
文摘Nanostructure engineering and composition rationalization are crucial for materials to become candidates for high-performance supercapacitor.Herein,a novel core-shell heterostructured electrode,combining CoS hollow nanorods with NiCoMn-layered double hydroxides(LDH)ternary metal nanosheets,were prepared on carbon cloth by reasonably controlled vulcanization and electrodeposition.By optimizing electrodeposition conditions,the material's structure and properties can be fine-tuned.The enhanced capacitance of the optimized carbon cloth(CC)@CoS/NiCoMn-LDH-300 electrode(4256.0 F g^(-1))lies in the open space provided by CoS and the establishment of a new charge transfer channel across the interfaces of CC@CoS/NiCoMn-LDH-300 nanosheets.This is further demonstrated by Density functional theory(DFT)simulations based on OHadsorption energy,which produces faster redox charge kinetics and significantly enhances the electrode's energy storage capacity.The hybrid supercapacitor,integrating the optimized CC@CoS/NiCoMn-LDH-300 electrode with active carbon,demonstrates the highest energy density of 86 Wh kg^(-1)(under the power density of 850 W kg^(-1))and the long cycle stability of 89.7%.This study aims to go beyond simple binary LDH by constructing a ternary LDH with a hierarchical core-shell heterostructure to provide an effective and feasible new concept for high-performance supercapacitor electrode materials via rational structure design.
基金Financial support from the National Natural Science Foundation of China(52302317)is gratefully acknowledged。
文摘Rechargeable magnesium batteries(RMBs)have garnered significant attention in energy storage applications due to their high capacity,low cost,and high safety.However,the strong polarization effect and slow kinetic de-intercalation of Mg^(2+)in the cathode limit their commercial application.This study presents a novel interface-coupled V_(2)CT_(x)@VS_(4)heterostructure through a one-step hydrothermal process.In this architecture,V_(2)CT_(x)and VS_(4)can mutually support their structural framework,which effectively prevents the structural collapse of V_(2)CT_(x)MXene and the aggregation of VS_(4).Crucially,interfacial coupling between V_(2)CT_(x)and VS_(4)induces strong V-S bonds,substantially enhancing structural stability.Benefiting from these advantages,the heterostructure exhibits high specific capacity(226 mAh g^(-1)at 100 mA g^(-1))and excellent long-cycle stability(89% capacity retention after 1000 cycles at 500 mA g^(-1)).Furthermore,the Mg^(2+)storage mechanism in the V_(2)CT_(x)@VS_(4)composite was elucidated through a series of ex-situ characterizations.This work provides a feasible strategy for designing V_(2)CT_(x)MXene-based cathodes with high capacity and extended cyclability for RMBs.
基金supported by the National Natural Science Foundation of China(No.22265017)the Open Fund of Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education(No.KF-21-04).
文摘In this work,the synthesis of uniform zeolitic imidazolate framework-coated Mo-glycerate spheres and their subsequent conversion into hierarchical architecture containing bimetallic selenides heterostructures and nitrogen-doped carbon shell are reported.Selenization temperature plays a significant role in determining the phases,morphology,and lithium-ion storage performance of the composite.Notably,the optimal electrode demonstrates an ultrahigh reversible capacity of 1298.2 mAh/g after 100 cycles at 0.2 A/g and an outstanding rate capability with the capacity still maintained 505.7 mAh/g after 300 cycles at 1.0 A/g,surpassing the calculated theoretical capacity according to individual component and most of the reported MoSe@C-or ZnSe@C-based anodes.Furthermore,ex-situ X-ray diffraction patterns reveal the combined conversion and alloying reaction mechanisms of the composite.
基金the financial support by the National Key Research and Development Program of China(No.2019YFA0708700)the National Natural Science Foundation of China(Nos.62305196,U23B2087 and 62375158)+4 种基金the China Postdoctoral Science Foundation(No.GZC20231498)the Qingdao Postdoctoral Innovation Project(No.QDBSH20240102078)the Postdoctoral Innovation Program of Shandong Province(No.SDCX-ZG-202400318)Science and Technology Research Project of Hubei Provincial Department of Education(No.D20212603)Hubei University of Arts and Science(No.2020kypytd002)。
文摘Surface adsorption plays a crucial role in various natural and industrial processes,particularly in the field of energy storage.The adsorption of sodium atoms on 2D layered materials can significantly impact their performance as carriers and electrodes in ion batteries.While it is commonly acknowledged that pristine graphene is not favorable for sodium ion adsorption,the suitability of other 2D materials with similar honeycomb symmetry remains unclear.In this study,we employ systematic first-principles calculations to explore interlayer interactions and electron transfer effects on sodium adsorption on 2D van der Waals(vdW)heterostructures(HTSs)surfaces.Our results demonstrate that sodium adsorption is energetically favorable on these substrates.Moreover,we find that the adsorption strength can be effectively tuned by manipulation of the electron accumulation or depletion of the layer directly interacting with the sodium atom.By stacking these layered materials with different electron abundancy to form vd W HTSs,the charge density of the substrate becomes tunable through interlayer charge transfer.In these vdW HTSs,the adsorption behavior of sodium is primarily controlled by the absorption layer and exhibits a linear correlation with its pz-band center.Additionally,we identify linear correlations between the sodium adsorption energies,the electron loss of the sodium atom,the interlayer charge transfer,and the heights of the adsorbed sodium atom.These discoveries underscore the impact of interlayer electron transfer and interactions on sodium ion adsorption on 2D vd W HTSs and providing new insights into material design for alkali atom adsorption.
基金supported by the Natural Science Foundation of Fujian Province of China(2022J01646)。
文摘The heterostructures incorporated with two or more distinctive two-dimensional(2D)materials have attracted great attention be-cause they could give rise to enhanced prop-erty in comparison with their individual counterparts.Here,a water-assisted two-step rapid physical vapor deposition(rPVD)method was explored and used to synthesize Bi_(2)Te_(3)-Sb_(2)Te_(3)lateral het-erostructures(LHS)successfully.The Bi_(2)Te_(3)-Sb_(2)Te_(3)LHS is in nearly uniform size,and grows along three particular orientations with the intersection angles of 120°.Inter-estingly,we found that the water molecules play a significant role in determining the growth orientation,namely whether it will grow along the vertical or lateral direction in 2D structure.Hence,a growth mechanism of LHS based on the water-assisted two-step rPVD was present,which can be used as a general strategy and extended to the growth of other 2D heterostruc-tures or homostructures,such as SnS-SnSe LHS and SnS-SnS lateral homostructures.Fur-thermore,the second-harmonic generation intensity of the Bi_(2)Te_(3)-Sb_(2)Te_(3)LHS is much stronger than that of the Bi_(2)Te_(3)/Sb_(2)Te_(3)vertical heterostructures(VHS).This work opens a new approach for the synthesis of water-assisted lateral 2D heterostructures or homostruc-tures and offers a new method to enhance the second-harmonic generation properties of topo-logical insulating materials.
基金supported by the National Natural Science Foundation of China(No.22302096)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(Nos.23KJB150039 and 24KJB150026)+1 种基金Natural Science Foundation of Zhejiang Province(No.LQ24E040002)the Natural Science Foundation of Huzhou City(No.2023YZ18).
文摘Rational developing high-performance and economically efficient dual-functional oxygen electrocatalysts to drive the lumberly reactivity rates of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)in Zn-air batteries is highly attractive,yet remains conceptually challenging.Herein,Ni/MnO heterostructure nanosheets and nanoparticles firmly anchored onto the N-doped carbon nanofibers(noted as Ni/MnO@N-C NS/NFs)for efficient bifunctional ORR/OER electrocatalysis are designed and realized through a facile electrospinning-pyrolysis-etching strategy.The epitaxial in situ grown Ni/MnO with enriched oxygen vacancies stimulated the charge redistribution in their coupling regions,which effectively optimizes the adsorption/desorption of O-related intermediates in ORR/OER.Benefiting from the Ni/MnO heterostructure moieties and the unique two-dimensional/one-dimensional(2D/1D)superstructure of carbon support with abundantly dispersive active species,the resultant Ni/MnO@N-C NS/NFs deliver robust ORR activity and OER property(an overpotential of 306 mV to obtain 10 mA·cm^(-2))with a smaller potential gap(ΔE=0.77 V)in alkaline electrolyte.More significantly,practical zinc-air battery building with Ni/MnO@N-C NS/NFs delivers a higher open circuit voltage,excellent output power density,and prominent durability with stable charging and discharging cycle life.The present work demonstrates a crucial understanding of building advanced heterostructure electrocatalysts with enriched oxygen vacancies for metal-air batteries application.
基金supported by the National Natural Science Foundation of China(Grant Nos.12404051,12347156,12174157,12074150,and 12174158)the National Key Research and Development Program of China(Grant No.2022YFA1405200)+2 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20230516)the Scientific Research Project of Jiangsu University(Grant No.550171001)support provided by the Deutsche Forschungsgemeinschaft(DFG,German Research Founda-tion)-TRR 288/2-422213477(project B06).
文摘Interlayer interactions in bilayer or multilayer electron systems have been studied extensively,and many exotic physical phenomena have been revealed.However,systematic investigations of the impact of interlayer interactions on magnonic physics are very few.Here,we use a van derWaals(vdW)honeycomb heterostructure as a platform to investigate the modulation of magnon properties in honeycomb AA-and AB-stacking heterostructures with ferromagnetic and antiferromagnetic interlayer interactions,including topological phases and thermal Hall conductivity.Our results reveal that interlayer interactions play a crucial role in modulating the magnonic topology and Hall transport properties of magnetic heterostructures,with potential for experimental realization.
基金supported by the National Natural Science Foundation of China(No.22465009)the Education Department of Guizhou Province(No.2021312)the Foundation of Guizhou Province(No.2019-5666).
文摘Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications.
基金supported by the Fund of Education Department of Shaanxi Provincial Government(No.23JP172)the National Natural Science Foundation of China(No.22309189)financial support from Xiaomi Young Talents Program.
文摘Extensive first-principles calculations have been performed to examine the electrochemical properties of Na-ion-intercalatable heterostructures formed by transitional metal dichalcogenides(MS_(2),where M=Ti,V,Nb and Mo)and blue phosphorus(BlueP),which have been reported as potential anode materials for rechargeable sodium-ion batteries.Upon formation of heterostructures,much improved structural stabilities have observed compared with the pristine MS_(2) and BlueP.Metallic T-TiS_(2),T-MoS_(2),H(T)-VS_(2) and H(T)-NbS_(2) would retain the conductive character after formation of heterostructures with BlueP,however,HTiS_(2)/BlueP and H-MoS_(2)/BlueP would undergo a semiconductor to metallic transition accompanied by Na intercalation.Moreover,the presence of relatively low diffusion barriers ranging from 0.04 eV to 0.08 eV,coupled with the suitable average open-circuit voltage spanning from 0.12 eV to 0.89 eV,guarantee exceptional charge-discharge rates and ensure the safety of battery performance.Among these heterostructures,H(T)-NbS_(2)/BlueP and T-TiS_(2)/BlueP exhibit best Na adsorption ability of up to 4 layers,corresponding to theoretical capacities of 570.2 and 746.7 mAh/g,respectively.These encouraging properties indicate that T-TiS_(2)/BlueP and H(T)-NbS_(2)/BlueP could serve as suitable anode materials for high-performance sodiumion batteries.
基金funded by the National Natural Science Foundation of China(No.52402106)the Natural Science Foundation of Heilongjiang Province Jointly Guided Project(No.LH2023B010)the Planning Project of Heilongjiang Province Education Department(No.LJYXL2022-036)。
文摘Direct borohydride hydrogen peroxide fuel cells(DBHPFCs)are emerging as a transformative technology for sustainable energy conversion.Despite their potential,their efficiency is largely hindered by the limitations of the anode catalyst.In response to this challenge,we have developed a novel series of Co-based heterojunction metal-organic framework(MOF)derivatives,supported on reduced graphene oxide(rGO)-modified nickel foam(NF),to enhance borohydride electrooxidation performance.Our synthesis involves the thermal transformation of a ZIF67-Co(OH)_(2)-rGO/NF precursor within a controlled temperature between 300 and 750℃,yielding distinct phase heterostructures and pristine Co and CoO,verified by X-ray diffraction(XRD)and transmission electron microscopy(TEM)analyses.Additionally,the Ultraviolet photoelectron spectroscopy and theoretical calculation result further validate the formation of the heterojunction and direction of electron transfer along the interface as well as the BH_(4)^(-)adsorption behavior across the heterointerface.Notably,the catalyst annealed at 600℃,designated Co-CoO@C-rGO/NF-600,exhibits an exceptional oxidation current density of 2.5 A cm^(-2)at 0 V vs.Ag/AgCl in an electrolyte containing 2 mol L^(-1)NaOH and 0.4 mol L^(-1)NaBH_(4)Furthermore,the Co-CoO@C-rGO/NF-600 catalyst demonstrates remarkable performance as the anode catalyst in a DBHPFC assembly,achieving a peak power density of 385.73 mW cm^(-2)and demonstrating the enduring operational stability.The superior electrocatalytic performance is primarily attributed to the synergistic effects of Co-CoO nanoparticles rich in active heterointerfaces and the superior electron mobility afforded by the rGO scaffold.These results not only deepen our understanding of anode catalyst design for DBHPFCs but also pave the way for breakthroughs in electrocatalytic technologies,driving forward the quest for sustainable energy solutions.
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.
