查看更多>>摘要：A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the develop-ment of high-energy-density ceramic-based capacitors.Although significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramics has been restricted due to environmental and health hazards of lead.Lead-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near future.However,the energy density of lead-free ceramics is still lagging behind that of lead-containing counterparts,severely limiting their appli-cations.Significant efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past decade.This review briefly dis-cusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial production.The prospects and challenges of lead-free ceramics for energy storage applications are also discussed.
查看更多>>摘要：The rapidly increasing production of lithium-ion batteries(LIBs)and their limited service time increases the number of spent LIBs,eventually causing serious environmental issues and resource wastage.From the per-spectives of clean production and the development of the LIB industry,the effective recovery and recycling of spent LIBs require urgent solutions.This study provides an overview of the current hydrometallurgical processes employed in the recycling of spent cathode materials,focusing on the leaching of valuable metals and their postprocessing.In particular,this research reviews the various leaching systems(inorganic acid,organic acid,and ammonia)and the separation of valuable metals,and then,recommendations for subsequent study are offered in an attempt to contribute to the development of highly efficient methods for recycling spent cathode materials.In addition,a range of existing technologies,such as solvent extraction,chemical precipitation,electrochemical deposition,and regeneration,for the postprocessing of leaching solutions are summarized.Finally,the promising technologies,existing challenges and suggestions with respect to the development of effective and environmentally friendly recycling methods for handling spent cathode materials are identified.
查看更多>>摘要：As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environ-mental fields.Among the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural enzymes.Owing to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and pro-mote their potential applications in both biomedical and environmental fields.Therefore,a comprehensive summary of activity regulatory strategies of MOF-based nanozymes is urgently needed.Firstly,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and morphologies.Then the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibac-terial,and cancer therapy were also introduced.Finally,the current challenges and future perspectives were discussed in depth.It is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes.
查看更多>>摘要：The lithium-ion batteries(LIBs)have been widely equipped in electric/hybrid electric vehicles(EVs/HEVs)and the portable electronics due to their excellent electrochemical performances.However,a large number of retired LIBs that consist of toxic substances(e.g.,heavy metals,electrolytes)and valuable metals(e.g.,Li,Co)will inevitably flow into the waste stream,and their incineration or landfill treatment will cause severe risks to ecosystem and human beings.The sustainable and efficient treatment or recycling of valuable resources from spent LIBs should be fully recognized for environmental and resource secu-rity.As one of the most important processes for spent LIBs recycling,the pretreatment is an indispensable step,which is directly related to the subsequent metal extraction and separation processes.Although considerable progresses have been made regarding the pretreatment technologies,there are few summarized reports concerning critical processes of spent LIBs recycling,especially combination of currently available recycling technologies with indus-trialized applications during pretreatments.Therefore,comprehensive review of the current prevailing pretreat-ment technologies in laboratory to existing scale-up applications is quite necessary to reveal cutting-edge development in the field of pretreatment.In this review,the current pretreatment technologies are systematically cate-gorized and introduced,along with critical discussions.This review focused on the various options for pretreat-ment processes itself,instead of general spent LIBs recy-cling technologies without the focused topics that have been sophisticatedly reviewed by previous studies.Here,the deactivation,discharge,dismantling,separation,liber-ation of active material and electrolyte treatment have been summarized with the in-depth discussion of the technology development and current status of each category.Finally,current states of industrial development are also reviewed and discussed for the development of efficient and envi-ronmentally friendly recycling technologies for future applications.This review tends to present a focused topic concerning the pretreatment of spent LIBs to potential readers with a comprehensive illustration of the develop-ment on both cutting-edge technologies and scale-up applications.
查看更多>>摘要：Lithium(Li)is a promising candidate for next-generation battery anode due to its high theoretical specific capacity and low reduction potential.However,safety issues derived from the uncontrolled growth of Li dendrite and huge volume change of Li hinder its practical appli-cation.Constructing dendrite-free composite Li anodes can significantly alleviate the above problems.Copper(Cu)-based materials have been widely used as substrates of the composite electrodes due to their chemical stability,excellent conductivity,and good mechanical strength.Copper/lithium(Cu/Li)composite anodes significantly regulate the local current density and decrease Li nucle-ation overpotential,realizing the uniform and dendrite-free Li deposition.In this review,Cu/Li composite methods including electrodeposition,melting infusion,and mechanical rolling are systematically summarized and discussed.Additionally,design strategies of Cu-based current collectors for high performance Cu/Li composite anodes are illustrated.General challenges and future development for Cu/Li composite anodes are presented and postulated.We hope that this review can provide a com-prehensive understanding of Cu/Li composite methods of the latest development of Li metal anode and stimulate more research in the future.
查看更多>>摘要：Potassium-ion batteries(PIBs)have gained significant attention as an alternative to lithium-ion bat-teries(LIBs)due to the abundance of potassium(K)and low cost.Nevertheless,the difficulty in finding appropriate electrode materials that can efficiently store the larger K ions has hindered their practical application.Herein,we report a novel anode material,N-doped multichannel car-bon nanofibers embedded with porous CoS nanoprisms(CSP@NMCNF),for high-performance PIBs.The CSP@NMCNF was synthesized using a two-step strategy comprising of the electrospinning of Co acetate hydroxide nanoprism/binary polymer blend and a subsequent heat treatment.The porous CoS nanoprisms with an anisotropic morphology were well aligned along the length axis of the N-doped multichannel carbon nanofibers,thus ensuring their structural stability during the repeated charge-dis-charge process.In addition,numerous pores facilitated the transport of electrons and ions.Accordingly,the CSP@NMCNF anode exhibited excellent electrochemical performance,delivering a high specific capacity of 368 mAh·g-1 at 0.5 A·g-1 after 200 cycles and excellent rate capability(232 mAh·g-1 at 2.0 A·g-1).
查看更多>>摘要：Solid polymer electrolytes(SPEs)with high ionic conductivity are desirable for solid-state lithium metal batteries(SSLMBs)to achieve enhanced safety and energy density.Incorporating nanofillers into a polymeric matrix to develop nanocomposite solid electrolytes(NCSEs)has become a promising method for improving the ionic conductivity of the SPEs.Here,a novel ZIF-8-functionalized NCSE was prepared for high-temperature SSLMBs using an in situ radical polymerization method.It is found that the ZIF-8 nanoparticles could reduce the crystallinity of polymer segments and offer a Lewis acid surface that promotes the dissociation of lithium bis(tri-fluoromethanesulfonyl)imide(LiTFSI)and stabilizes the TFSI-anion movement.Thus,the as-prepared NCSE exhibits an outstanding ionic conductivity of 1.63 × 10-3 S·cm-1,an electrochemical stability window of 5.0 V at 80 ℃,and excellent interface compatibility with lithium metal anode with a stable polarization over 2000 h.Fur-thermore,the assembled SSLMBs with LiFePO4 cathode show dendrite-free Li-metal surface,good rate capability,and stable cycling stability with a capacity retention of 70％over 1000 cycles at a high temperature of 80 ℃.This work provides valuable insights into promoting the ionic conductivity of SPEs.
查看更多>>摘要：The interfacial characteristics of the Li metal anode(LMA)play a crucial role in its overall performance.Despite various materials being applied to modify the interface,a comprehensive understanding of their specific mechanisms remains to be investigated.Herein,we have prepared carbon cloth(CC)frameworks with their surfaces modified using ferromagnetic metal/LiF heterogeneous films(TM-LiF-CC)as the substrate for LMA,which exhibit superior electrochemical performance.Utilizing ferro-magnetic Co as a representative example,our study demonstrates that the enhanced performance of Co-LiF-CC,compared to bare CC,is attributed to the spin-polarized interface contributed by the Co/LiF heterostruc-ture.Co and LiF play individual roles in redistributing electrons and Li+to promote homogeneous Li deposition.Co nanoparticles play a crucial role in generating strong surface capacitance by storing electrons in spin-split bands,while LiF,with low surface diffusion barriers,ensures fast transportation of Li+.The Co-LiF-CC@Li electrodes deliver long lives of 7400 and 3600 h at 1 and 2 mA·cm-2 in symmetric cells,respectively;moreover,they enable full batteries with high and durable capacities,particularly when the N/P ratios are low(3.3 or even 1.7).
查看更多>>摘要：Quasi-solid-state lithium metal batteries(QSSLMBs)assembled with polyvinyl idene fluoride(PVDF)are a promising class of next-generation rechargeable batteries due to their safety,high energy density,and superior interfacial properties.However,PVDF has a series of inherent drawbacks such as low ionic conductivity,ease of crystallization,and hydrophobic character that leading to poor cell properties.To tackle these issues,a lignin-reinforced PVDF electrolyte is pro-posed in this work to solve these drawbacks of PVDF and enhance the comprehensive performance of QSSBs.The lithophilic polar groups of lignin can promote uniform deposition of Li on the electrodes.Cooperating with the improved mechanical properties can efficiently prevent Li dendrites penetration through the separator.In addition,more active sites provided by lignin can also enhance Li+transport and lead to a faster electrochemical reaction kinetic.Benefitting from the ingenious design,Li sym-metric cells with 5％lignin-PVDF quasi-solid-state elec-trolyte can operate for 900 h at a high current density/capacity of 5 mA·cm-2/5 mAh·cm-2,while short-circuiting occurs after 56 h for the counterpart(pure PVDF).Moreover,a full cell of Li/5％lignin-PVDF/LFP cell demonstrates a high capacity of 96.2 mAh·g-1 after 2000 cycles at 10 C.This work is expected to open up promising opportunities to develop other high-energy/power-density QSSLMBs.
查看更多>>摘要：Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state elec-trolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithia-tion-induced particle fracture and conductivity lost tend to be the main issues.In this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,respectively.In addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI layer.As a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly improved.Consequently,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in SSB.For example,high specific capacity of 3224.6 mAh·g-1 and long cycling durability of 200 cycles are achieved.This work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.
NETL
NSTL
万方数据