查看更多>>摘要：Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing with lithium metal,hindering practical applications.Herein,we introduce a flexible metal-organic framework(MOF:NUS-6)-incorporated polymeric layer,denoted as NP,designed to pro-tect the sodium superionic conductor(NASICON)-type Li1.3Alo.3Ti1.7(PO4)3(LATP)electrolyte from Li metal anodes.The NP matrix establishes a soft interface with the LATP surface,effectively reducing voids and gaps that may arise between the LATP electrolyte and Li metal.Moreover,the MOF component in NP enhances ionic conductivity,offers abundant Li+transport sites,and provides hierarchical ion channels,ensuring a homogeneous Li+flow and thus effectively inhibiting Li dendrite formation.Utilizing NP,we fabricate Li symmetrical cells cycled for over 1600 h at 0.2 mA cm-2 and all-solid-state Li|NP-LATP|LiFePO4 batteries,achieving a remarkable 99.3％capacity retention after 200 cycles at 0.2 C.This work outlines a general strategy for designing long-lasting and stable solid-state Li metal batteries.
查看更多>>摘要：Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the estab-lishment of a stable interphase through the implementation of a functional electrolyte strategy remains challenging.Especially when the battery is operated under high temperature,the trace water present in the electrolyte will accelerate the hydrolysis of the electrolyte and the resulting HF will further erode the interphase.In order to enhance the long-term cycling performance of graphite/LiNi0.8Co0.1Mn0.1O2(NCM811)LIBs,herein,Tolylene-2,4-diisocyanate(TDI)additive containing lone-pair electrons is employed to formulate a novel bifunctional electrolyte aimed at eliminating H2O/HF generated at ele-vated temperature.After 1000 cycles at 25 ℃,the battery incorporating the TDI-containing electrolyte exhibits an impressive capacity retention of 94％at 1 C.In contrast,the battery utilizing the blank elec-trolyte has a lower capacity retention of only 78％.Furthermore,after undergoing 550 cycles at 1 C under 45 ℃,the inclusion of TDI results in a notable enhancement of capacity,increasing it from 68％to 80％.This indicates TDI has a favorable influence on the cycling performance of LIBs,especially at elevated temperatures.The analysis of the film formation mechanism suggests that the lone pair of electrons of the isocyanate group in TDI play a crucial role in inhibiting the generation of H2O and HF,which leads to the formation of a thin and dense interphase.The existence of this interphase is thought to substan-tially enhance the cycling performance of the LIBs.This work not only improves the performance of gra-phite/NCM811 batteries at room temperature and high temperature by eliminating H2O/HF but also presents a novel strategy for advancing functional electrolyte development.
查看更多>>摘要：Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evo-lution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO2).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorp-tion strength of*H and*OH on Ni is optimized,thus resulting in superior electrocatalytic performance of O-Ni/WO2 in alkaline HER/HOR.The Tafel slope of O-Ni/WO2@NF for HER is 56 mV dec-1,and the kinetic current density of O-Ni/WO2 for HOR reaches 4.85 mA cm-2,which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts.
查看更多>>摘要：Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical applica-tion is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible depo-sition of Li2S.To address these issues,a novel composite,using electrospinning technology,consisting of Fe3Se4 and porous nitrogen-doped carbon nanofibers was designed for the interlayer of LSBs.The porous carbon nanofiber structure facilitates the transport of ions and electrons,while the Fe3Se4 material adsorbs lithium polysulfides(LiPSs)and accelerates its catalytic conversion process.Furthermore,the Fe3Se4 material interacts with soluble LiPSs to generate a new polysulfide intermediate,LixFeSy complex,which changes the electrochemical reaction pathway and facilitates the three-dimensional deposition of Li2S,enhancing the reversibility of LSBs.The designed LSB demonstrates a high specific capacity of 1529.6 mA h g-1 in the first cycle at 0.2 C.The rate performance is also excellent,maintaining an ultra-high specific capacity of 779.7 mA h g-1 at a high rate of 8 C.This investigation explores the mech-anism of the interaction between the interlayer and LiPSs,and provides a new strategy to regulate the reaction kinetics and Li2S deposition in LSBs.
查看更多>>摘要：Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most fea-sible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the process.However,for hydrogen produced via water electrol-ysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to $1/kgH2.To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the system.In this paper,the types of water electrolysis systems and the lim-itations of water electrolysis system components are explained.We suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology.
查看更多>>摘要：O3-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na+diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped O3-type high entropy oxide Na(Fe0.2Co0.15Cu0.05Ni0.2Mn0.2Ti0.2)B0.02O2(NFCCNMT-B0.02)is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B0.02 exhibits impressive cycling performance(capacity retention of 95％and 82％after 100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g-1 at 10 C).Furthermore,the NFCCNMT-B0.02 demonstrates a superior wide-temperature performance,maintaining the same capacity level(113.4 mAh g-1@-20 ℃,121 mAh g-1@25 ℃,and 119 mAh g-1@60 ℃)and superior cycle stability(90％capacity retention after 100 cycles at 1 C at-20 ℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 Å3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na+diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature.
查看更多>>摘要：The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H8ETTB)at the SnO2 ETL/perovskite interface.Firstly,the interaction of H8ETTB with the SnO2 sur-face,facilitated by its carboxyl groups,is effective in passivating surface defects caused by non-coordinated Sn and O vacancies.This interaction enhances the conductivity of the SnO2 film and adjusts energy levels,leading to enhanced charge carrier transport.Simultaneously,H8ETTB can passivate non-coordinated Pb2+ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline quality.More importantly,the H8ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of UV.Consequently,the champion PSC based on SnO2-H8ETTB achieves an impressing efficiency of 23.32％and significantly improved photostability compared with the control device after continuous exposure to intense UV radiation.In addition,the Cs0.05(FA0.95MA0.05)0.95Pb(I0.95Br0.05)3 based device can achieve maximum efficiency of 24.01％,demonstrating the effectiveness and universality of this strategy.Overall,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs.
查看更多>>摘要：Transition metal sulfides have high theoretical capacities and are considered as potential anode materials for sodium-ion batteries.However,due to low inherent conductivity and significant volume expansion,the electrochemical performance is greatly limited.In this study,a nickel/manganese sulfide material(Ni0.96Sx/MnSy-NC)with adjustable sulfur vacancies and heterogeneous hollow spheres was prepared using a simple method.The introduction of a concentration-adjustable sulfur vacancy enables the gener-ation of a heterogeneous interface between bimetallic sulfide and sulfur vacancies.This interface collec-tively creates an internal electric field,improving the mobility of electrons and ions,increasing the number of electrochemically active sites,and further optimizing the performance of Na+storage.The direction of electron flow is confirmed by Density functional theory(DFT)calculations.The hollow nano-spherical material provides a buffer for expansion,facilitating rapid transfer kinetics.Our innova-tive discovery involves the interaction between the ether-based electrolyte and copper foil,leading to the formation of Cu9S5,which grafts the active material and copper current collector,reinforcing mechan-ical supporting.This results in a new heterostructure of Cu9S5 with Ni0.96Sx/MnSy,contributing to the sta-bilization of structural integrity for long-cycle performance.Therefore,Ni0.96Sx/MnSy-NC exhibits excellent electrochemical properties following our modification route.Regarding stability performance,Ni0.96Sx/MnSy-NC demonstrates an average decay rate of 0.00944％after 10,000 cycles at an extremely high current density of 10000 mA g-1.A full cell with a high capacity of 304.2 mA h g-1 was also success-fully assembled by using Na3V2(PO4)3/C as the cathode.This study explores a novel strategy for inter-face/vacancy co-modification in the fabrication of high-performance sodium-ion batteries electrode.
查看更多>>摘要：Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)cathode enhances the kinetics of the redox processes of the insulating sulfur,which also arouses the notorious shuttle effect,leading to serious loss of S species and corrosion of Li anode.To get a balance between the shuttle restraining and the kinetic property,a combined strategy of electrolyte regulation and cathode modification is proposed via introducing 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoroprpyl ether(HFE)instead of 1,2-dimethoxyethane(DME),and SeS7 instead of S8.The introduction of HFE tunes the solvation structure of the LiTFSI and the dissolution of intermediate polysulfides with Se doping(LiPSSes),and optimize the interface stability of the Li anode simultaneously.The minor Se substitution compensates the decrease in kinetic due to the decreased solubility of LiPSs.In this way,the Li-SeS7 bat-teries deliver a reversible capacity of 1062 and 1037 mAh g-1 with 2.0 and 5.5 mg SeS7 cm-2 loading con-dition,respectively.Besides,an electrolyte-electrode loading model is established to explain the relationship between the optimal electrolyte and cathode loading.It makes more sense to guide the elec-trolyte design for practical Li-S batteries.
查看更多>>摘要：Cu catalysts,known for their unparalleled catalytic capabilities due to their unique electronic structure,have faced inherent challenges in maintaining long-term effectiveness under harsh hydrogenation con-ditions.Here,we demonstrate a molybdenum-mediated redispersion behavior of Cu under high-temperature oxidation conditions.The oxidized Cu nanoparticles with rich metal-support interfaces tend to dissolve into the MoO3 support upon heating to 600 ℃,which facilitates the subsequent regeneration in a reducing atmosphere.A similar redispersion phenomenon is observed for Cu nanoparticles supported on ZnO-modified MoO3.The modification of ZnO significantly improves the performance of the Cu cata-lyst for CO2 hydrogenation to methanol,with the high activity being well maintained after four repeated oxidation-reduction cycles.In situ spectroscopic and theoretical analyses suggest that the interaction involved in the formation of the copper molybdate-like compound is the driving force for the redispersion of Cu.This method is applicable to various Mo-based oxide supports,offering a practical strategy for the regeneration of sintered Cu particles in hydrogenation applications.
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