Photo-assisted Li-O2 batteries(LOBs)have remained a prominent and growing field over the past several years.However,the presence of slow oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),large charging ...Photo-assisted Li-O2 batteries(LOBs)have remained a prominent and growing field over the past several years.However,the presence of slow oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),large charging and discharging overpotentials,and unstable cycle life lead to low energy efficiency,thus limiting their commercial application.The rational design and synthesis of photocathode materials are effective ways to solve the above existing problems of photo-assisted LOB systems.Herein,the recent advances in the design and preparation of photocathode materials for photo-assisted LOBs were summarized in this review.First,we summarize the basic principles and comprehension of the reaction mechanism for photo-assisted LOBs.The second part introduces the latest research progress on photocathode materials.The third section describes the relationship between the structureproperties and electrochemistry of different photocathodes.In addition,attempts to construct efficient photocathode materials for photo-assisted LOBs through vacancy engineering,localized surface plasmon resonance(LSPR),and heterojunction engineering are mainly discussed.Finally,a discussion of attempts to construct efficient photocathode materials using other approaches is also presented.This work will motivate the preparation of stable and efficient photocathode materials for photo-assisted LOBs and aims to promote the commercial application of rechargeable photo-assisted LOBs energy storage.展开更多
Rechargeable lithium-oxygen(Li-O_(2))batteries have attracted wide attention due to their high energy density.However,the sluggish cathode kinetics results in high overvoltage and poor cycling performance.Ruthenium(Ru...Rechargeable lithium-oxygen(Li-O_(2))batteries have attracted wide attention due to their high energy density.However,the sluggish cathode kinetics results in high overvoltage and poor cycling performance.Ruthenium(Ru)-based electrocatalysts have been demonstrated to be promising cathode catalysts to promote oxygen evolution reaction(OER).It facilitates decomposition of lithium peroxide(Li_(2)O_(2))by adjusting Li_(2)O_(2) morphologies,which is due to the strong interaction between Ru-based catalyst and superoxide anion(O_(2))intermediate.In this review,the design strategies of Ru-based electrocatalysts are introduced to enhance their OER catalytic kinetics in Li-O_(2) batteries.Different configurations of Ru-based catalysts,including metal particles(Ru metal and alloys),single-atom catalysts,and Ru-loaded compounds with various substrates(carbon materials,metal oxides/sulfides),have been summarized to regulate the electronic structure and the matrix architecture of the Ru-based electrocatalysts.The structure-property relationship of Ru-based catalysts is discussed for a better understanding of the Li_(2)O_(2) decomposition mechanism at the cathode interface.Finally,the challenges of Ru-based electrocatalysts are proposed for the future development of Li-O_(2) batteries.展开更多
Rechargeable lithium-oxygen(Li-O2)batteries have appeal to enormous attention because they demonstrate higher energy density than the state-of-the-art Li-ion batteries.Whereas,their practical application is impeded by...Rechargeable lithium-oxygen(Li-O2)batteries have appeal to enormous attention because they demonstrate higher energy density than the state-of-the-art Li-ion batteries.Whereas,their practical application is impeded by several challenging problems,such as the low energy round trip efficiencies and the insufficient cycle life,due to the cathode passivation caused by the accumulation of discharge products.Developing efficient catalyst for oxygen reduction and evolution reactions is effective to reduce the overpotentials in Li-O2cells.In our work,we report a Co3O4modified Ag/g-C3N4nanocomposite as a bifunctional cathode catalyst for Li-O2cells.The g-C3N4substrate prevents the accumulation of Ag and Co3O4nanoparticles and the presence of Ag NPs improves the surface area of g-C3N4and electronic conductivity,significantly improving the oxygen reduction/evolution capabilities of Co3O4.Due to a synergetic effect,the Ag/g-C3N4/Co3O4nanocomposite demonstrates a higher catalytic activity than each individual constituent of Co3O4or Ag/g-C3N4for the ORR/OER on as catalysts in Li-O2cells.As a result,the Ag/gC3N4/Co3O4composite shows impressive electrochemical performance in a Li-O2battery,including high discharge capacity,small gap between charge and discharge potential,and high cycling stability.展开更多
Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aque...Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aqueous Li-O_(2)batteries to enhance their discharge capacity and reduce charge overpotential.However,the shuttle effect of RMs in the electrolyte solution usually leads to corrosion of the Li metal anode and uneven Li deposition on the anode surface,resulting in unwanted consumption of electrocatalysts and deterioration of the cells.It is therefore necessary to take some measures to prevent the shuttle effect of RMs and fully utilize the soluble electrocatalysts.Herein,we summarize the strategies to suppress the RM shuttle effect reported in recent years,including electrolyte additives,protective separators and electrode modification.The mechanisms of these strategies are analyzed and their corresponding requirements are discussed.The electrochemical properties of Li-O_(2)batteries with different strategies are summarized and compared.The challenges and perspectives on preventing the shuttle effect of RMs are described for future study.This review provides guidance for achieving shuttle-free redox mediation and for designing Li-O_(2)cells with a long cycle life,high energy efficiency and highly reversible electrochemical reactions.展开更多
Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy...Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy-rich TiO_(2)(Vo-TiO_(2))nanoparticles(NPs)uniformly dispersing on Ti_(3)C_(2)T_(x)(Vo-TiO_(2)/Ti_(3)C_(2) T_(x))with excellent lithiophilicity feature are presented as effective composite anodes,on which a dense and uniform Li growth behavior is observed.Based on electrochemical studies,mutiphysics simulation and theoretical calculation,it is found that Vo-TiO_(2) coupling with three dimensional(3 D)conductive Ti_(3)C_(2) T_(x) MXene forms highly ordered lithiophilic sites which succeed in guiding Li ions flux and adsorption,thus modulating the uniform Li nucleation and growth.As a result,this composite electrode is capable of preserving Li with high areal capacity of~10 mAh cm^(-2) without the presence of dendrites and large volume expansion.Consequently,the as-prepared Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anode shows outstanding performance including low voltage hysteresis(~19 mV)and superior durability(over 750 h).When assembling with the Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anodes,lithium-oxygen batteries also deliver enhanced cycling stability and improved rate performance.This work demonstrates the effectiveness of oxygen vacancies in guiding Li nucleating and plating behavior at initial stage and brings a promising strategy for promoting the development of advanced Li metal-based batteries.展开更多
Lithium-oxygen(Li-O_(2))batteries are an emerging energy storage alternative with the potential to meet the recent increase in demand for high-energy-density batteries.From a practical viewpoint,lithium-air(Li-Air)bat...Lithium-oxygen(Li-O_(2))batteries are an emerging energy storage alternative with the potential to meet the recent increase in demand for high-energy-density batteries.From a practical viewpoint,lithium-air(Li-Air)batteries using ambient air instead of pure oxygen could be the final goal.However,the slow oxygen reduction and evolution reactions interfere with reversible cell operation during cycling.Therefore,research continues to explore various catalyst materials.The present study attempts to improve the performance of Li-Air batteries by using porphyrin-based materials known to have catalytic effects in Li-O_(2) batteries.The results confirm that the iron phthalocyanine(FePc)catalyst not only exhibits a catalytic effect in an air atmosphere with a low oxygen fraction but also suppresses electrolyte decomposition by stabilizing superoxide radical ions(O_(2)^(−))at a high voltage range.Density functional theory calculations are used to gain insight into the exact FePc-mediated catalytic mechanism in Li-Air batteries,and various ex situ and in situ analyses reveal the reversible reactions and structural changes in FePc during electrochemical reaction.This study provides a practical solution to ultimately realize an air-breathing battery using nature-friendly catalyst materials.展开更多
Highly active cathode catalysts for efficient formation/decomposition of Li_(2)O_(2)are essential for the performance improvement of lithium-oxygen batteries(LOBs).In this study,a grain-refining Co_(0.85)Se catalyst w...Highly active cathode catalysts for efficient formation/decomposition of Li_(2)O_(2)are essential for the performance improvement of lithium-oxygen batteries(LOBs).In this study,a grain-refining Co_(0.85)Se catalyst with a lattice spacing of 2.69 A of(101)plane closely matching with the(100)plane(2.72A)of Li_(2)O_(2)was applied for high-performance LOBs.Highly(101)plane exposed Co_(0.85)Se@CNT was synthesized by a simple one-pot hydrothermal method.The Co_(0.85)Se with the lattice matching effect not only led to the efficient conversion and polarized growth of Li_(2)O_(2),but also prevented the formation of byproducts.Density functional theory(DFT)calculations reveal that Co_(0.85)Se(101)plane has the intrinsic catalytic ability to generate/decompose Li_(2)O_(2)during ORR/OER process,due to its homogeneous electron distribution,suitable adsorption energy,and promoted Li_(2)O_(2)growth kinetics.As a consequence,the(101)plane highly exposed Co_(0.85)Se@CNT-80 electrode exhibited remarkable cycle stability over 2400 h at 100 mA/g and 290cycles at 500 mA/g,which is about 2 times longer than other electrodes.展开更多
Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited...Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited density of active sites.Here we present C_(60) as a metal-free cathode catalyst for LOBs,using density functional theory calculations and experimental verifications.The lithiation reactions on the pristine carbon sites of C_(60) are energetically favorable due to its curvedπ-conjugation over the pentagon-hexagon networks.The kinetic analysis specifically reveals low energy barriers for Li_(2)O_(2) decomposition and Li diffusion on C_(60).Consequently,C_(60) exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon nanotubes.Our electrochemical measurements validate the predictions,notably demonstrating that the intrinsic activity of C_(60) is comparable to that of noble metals.展开更多
A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses the...A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves conductivity.mPR-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain dispersion.Integrating this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 cycles.In situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen reactions.Ex situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability tests.The present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.展开更多
Li-ion batteries have played a key role in the portable electronics and electrification of transport in modern society. Nevertheless,the limited highest energy density of Li-ion batteries is not sufficient for the lon...Li-ion batteries have played a key role in the portable electronics and electrification of transport in modern society. Nevertheless,the limited highest energy density of Li-ion batteries is not sufficient for the long-term needs of society. Since lithium is the lightest metal among all metallic elements and possesses the lowest redox potential of.3.04 V vs. standard hydrogen electrode, it delivers the highest theoretical specific capacity of 3860 mA h g^(-1) and a high working voltage of full batteries which causes a great interest in electrochemical energy storage systems. Lithium-sulfur, lithium-oxygen and corresponding all solid state batteries based on metal lithium anode have received widely attention owing to their high energy densities. However, the problems in the cathode,electrolyte and anode of these three systems restrict their practical application. In this review, the research status and problems of these three energy storage systems are summarized and the challenges and future perspectives are also outlined.展开更多
Ti3C2 belongs to MXenes family,which is a new two-dimensional material and has been applied in many fields.With simple method of hydrothermal and high temperature calcination,nano structured Ni/Ti3C2Tx hybrid was synt...Ti3C2 belongs to MXenes family,which is a new two-dimensional material and has been applied in many fields.With simple method of hydrothermal and high temperature calcination,nano structured Ni/Ti3C2Tx hybrid was synthesized.The stable layer structure of Ti3C2 MXene providing high surface area as well as excellent electronic conductivity are beneficial for deposition and decomposition of discharge product Li2O2.Furthermore,possessing special catalytic activity,Ni nanoparticles with size of about 20 nm could accelerate Li2O2 breaking down.Taking advantage of two kinds of materials,Ni/Ti3C2Tx hybrid as cathode of Li-O2 battery can achieve a maximal specific capacity of 20,264 mAh/g in 100 mA/g and 10,699 mAh/g in 500 mA/g at the first cycle.This work confirms that the prepared Ni/Ti3C2Tx hybrid exhibiting better cycling stability points out a new guideline to improve the electrochemical performance of lithium-oxygen batteries.展开更多
Organic ionic plastic crystals (OIPCs) composed of 1-ethyl-1-methyl pyrrolidinium bis(fluorosulfonyl) imide (P12FSI) and lithium bis(fluorosulfonyl)imide (LiFSI) was used as electrolyte for lithium-oxygen batteries. S...Organic ionic plastic crystals (OIPCs) composed of 1-ethyl-1-methyl pyrrolidinium bis(fluorosulfonyl) imide (P12FSI) and lithium bis(fluorosulfonyl)imide (LiFSI) was used as electrolyte for lithium-oxygen batteries. Since P12FSI-LiFSI electrolyte exhibited high ionic conductivity, good chemical stability and wide electrochemical window, the battery showed good rate capability, excellent cycling stability and can be operated stably for 320 cycles under a fixed capacity of 500 mAh/gcarbon. The use of OIPCs electrolyte could provide a new avenue for the development of high-performance Li-O2 batteries.展开更多
Lithium-oxygen(Li-O_(2))batteries have attracted considerable attention due to their high theoretical energy density.However nonrenewable and high-cost electrode materials have limited their progress.Herein,the author...Lithium-oxygen(Li-O_(2))batteries have attracted considerable attention due to their high theoretical energy density.However nonrenewable and high-cost electrode materials have limited their progress.Herein,the authors design and fabricate a three-dimensional freestanding bi-biomass egg-sugarcane(Egg-SC)electrode with excellent structure and performance as the cathode for Li-O_(2) batteries.The open,interconnected microchannels derived from the natural SC can provide sufficient pathways for O_(2) gas diffusion.The heteroatom-doped hollow carbon spheres(HD-HCS)obtained via biomass egg supply many of the triphase active sites for the formation and decomposition of the discharge products of Li2O_(2).Benefiting from the unique nature and structure of the cathode,Li-O_(2) batteries show high-rate capacity of 8.07 mAh cm^(-2) and superior cycle stability of 294 cycles at a current density of 0.1 mA cm^(-2).The excellent performance and structure of the bi-biomass cathode possess great application potential in nature-inspired materials design for the cathodes of Li-O_(2) batteries.展开更多
Developing excellent cathode catalysts with superior catalytic activities is essential for the practical application of aprotic lithium-oxygen batteries(LOBs).Herein,we successfully synthesized nitrogen-doped hollow m...Developing excellent cathode catalysts with superior catalytic activities is essential for the practical application of aprotic lithium-oxygen batteries(LOBs).Herein,we successfully synthesized nitrogen-doped hollow mesoporous carbon spheres encapsulated with molybdenum disulfide(MoS_(2))nanosheets as the cathode catalyst for rechargeable LOBs,and the relationship between the battery performance and structural characteristics was intensively researched.We found that the synergistic effect of the nitrogen-doped mesoporous carbon and MoS_(2)nanosheets endows superior electrocatalytic activities to the composite catalyst.On the one hand,the nitrogen-doped mesoporous carbon could enable fast charge transfer and effectively accommodate more discharging products in the composite skeleton.On the other hand,the thin MoS_(2)nanosheets could promote mass transportation to facilitate the revisable formation and decomposition of the Li2O2 during oxygen reduction reaction and oxygen evolution reaction,and the side reactions were also prevented,apparently due to their full coverage on the composite surfaces.As a result,the catalytic cathode loaded with 2H-MoS_(2)-modified nitrogen-doped hollow mesoporous carbon spheres exhibited excellent electrochemical performance in terms of large discharge-/charge-specific capacities with low overpotentials and extended cycling life,and they hold great promise for acting as the cathode catalyst for high-performance LOBs.展开更多
Lithium-oxygen(Li-O_(2))batteries have a great potential in energy storage and conversion due to their ultra-high theoretical specific energy,but their applications are hindered by sluggish redox reaction kinetics in ...Lithium-oxygen(Li-O_(2))batteries have a great potential in energy storage and conversion due to their ultra-high theoretical specific energy,but their applications are hindered by sluggish redox reaction kinetics in the charge/discharge processes.Redox mediators(RMs),as soluble catalysts,are widely used to facilitate the electrochemical processes in the Li-O_(2)batteries.A drawback of RMs is the shuttle effect due to their solubility and mobility,which leads to the corrosion of a Li metal anode and the degradation of the electrochemical performance of the batteries.Herein,we synthesize a polymer-based composite protective separator containing molecular sieves.The nanopores with a diameter of 4Åin the zeolite powder(4A zeolite)are able to physically block the migration of 2,2,6,6-tetramethylpiperidinyloxy(TEMPO)molecules with a larger size;therefore,the shuttle effect of TEMPO is restrained.With the assistance of the zeolite molecular sieves,the cycle life of the Li-O_(2)batteries is significantly extended from~20 to 170 cycles at a current density of 250 mA·g^(-1)and a limited capacity of 500 mAh·g^(-1).Our work provides a highly effective approach to suppress the shuttle effects of RMs and boost the electrochemical performance of Li-O_(2)batteries.展开更多
The polymer electrolyte based lithium-oxygen battery has showed higher safety than that of organic liquid electrolyte.However,the energy efficiency and cycling stability are still the challenges for the practical appl...The polymer electrolyte based lithium-oxygen battery has showed higher safety than that of organic liquid electrolyte.However,the energy efficiency and cycling stability are still the challenges for the practical application of lithium-oxygen battery.Herein,the 1,4 para benzoquinone has been demonstrated as dual-function redox mediator for promoting both oxygen reduction and oxygen evolution reactions of lithium-oxygen battery with polymer electrolyte,which have been confirmed by the Cyclic Voltammetry and discharge/charge test of battery under O_(2) gas,as well as the theoretical calculations.Furthermore,the composite cathode that in-situ constructed by polymerizing electrolyte precursors with redox me-diator can be beneficial for the electrochemical reactions.Combing composite cathode and lithium ions source,the polymer electrolyte based lithium-oxygen batteries can operate for long lifetime with low charge potentials and good rate performances.Thus,this work has highlighted the promising implementation of lithium-oxygen battery based on polymer electrolyte,in which the dual-function redox mediator are employed for both discharge and recharge processes.展开更多
The recent boom in large-scale energy storage system promotes the development of lithium-oxygen batteries because of their high theo retical energy density.However,their applications are still limited by the sluggish ...The recent boom in large-scale energy storage system promotes the development of lithium-oxygen batteries because of their high theo retical energy density.However,their applications are still limited by the sluggish kinetic,insoluble discharge product deposition and the undesired parasitic reaction.Herein,the free-standing nitrogen doped reduced graphene oxide/Co(OH)_(2)(NRGO/Co(OH)_(2)) composite films were prepared by a facile hydrothermal method,The NRGO/Co(OH)_(2) composite films display interconnected three-dimensional conductive network,which can not only promote the diffusion of O2 and the transport of electrolyte ions,but also provide abundant storage space for discharge products.Moreover,the introduction of nitrogen-containing functional groups results in improved conductivity and electron adsorption ability,which can facilitate electron transport and enhance the surface catalytic activity.Combining with excellent catalytic performance,the lithium-oxygen batteries with NRGO/Co(OH)_(2) composite film cathodes deliver low charge overpotential and excellent cycling performance.展开更多
Aprotic lithium-oxygen(Li-O_(2))batteries represent a promising next-generation energy storage system due to their extremely high theoretical specific capacity compared with all known batteries.Their practical realiza...Aprotic lithium-oxygen(Li-O_(2))batteries represent a promising next-generation energy storage system due to their extremely high theoretical specific capacity compared with all known batteries.Their practical realization is impeded,however,by the sluggish kinetics for the most part,resulting in high overpotential and poor cycling performance.Due to the high catalytic activity and favorable stability of Co-based transition metal oxides,they are regarded as the most likely candidate catalysts,facilitating researchers to solve the sluggish kinetics issue.Herein,this review first presents recent advanced design strategies for Co-based transition metal oxides in Li-O_(2)batteries.Then,the fundamental insights related to the catalytic processes of Co-based transition metal oxides in traditional and novel Li-O_(2)electrochemistry systems are summarized.Finally,we conclude with the current limitations and future development directions of Co-based transition metal oxides,which will contribute to the rational design of catalysts and the practical applications of Li-O_(2)batteries.展开更多
文摘Photo-assisted Li-O2 batteries(LOBs)have remained a prominent and growing field over the past several years.However,the presence of slow oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),large charging and discharging overpotentials,and unstable cycle life lead to low energy efficiency,thus limiting their commercial application.The rational design and synthesis of photocathode materials are effective ways to solve the above existing problems of photo-assisted LOB systems.Herein,the recent advances in the design and preparation of photocathode materials for photo-assisted LOBs were summarized in this review.First,we summarize the basic principles and comprehension of the reaction mechanism for photo-assisted LOBs.The second part introduces the latest research progress on photocathode materials.The third section describes the relationship between the structureproperties and electrochemistry of different photocathodes.In addition,attempts to construct efficient photocathode materials for photo-assisted LOBs through vacancy engineering,localized surface plasmon resonance(LSPR),and heterojunction engineering are mainly discussed.Finally,a discussion of attempts to construct efficient photocathode materials using other approaches is also presented.This work will motivate the preparation of stable and efficient photocathode materials for photo-assisted LOBs and aims to promote the commercial application of rechargeable photo-assisted LOBs energy storage.
基金the National Natural Science Foundation of China(22325902 and 51671107)Haihe Laboratory of Sustainable Chemical Transformations.
文摘Rechargeable lithium-oxygen(Li-O_(2))batteries have attracted wide attention due to their high energy density.However,the sluggish cathode kinetics results in high overvoltage and poor cycling performance.Ruthenium(Ru)-based electrocatalysts have been demonstrated to be promising cathode catalysts to promote oxygen evolution reaction(OER).It facilitates decomposition of lithium peroxide(Li_(2)O_(2))by adjusting Li_(2)O_(2) morphologies,which is due to the strong interaction between Ru-based catalyst and superoxide anion(O_(2))intermediate.In this review,the design strategies of Ru-based electrocatalysts are introduced to enhance their OER catalytic kinetics in Li-O_(2) batteries.Different configurations of Ru-based catalysts,including metal particles(Ru metal and alloys),single-atom catalysts,and Ru-loaded compounds with various substrates(carbon materials,metal oxides/sulfides),have been summarized to regulate the electronic structure and the matrix architecture of the Ru-based electrocatalysts.The structure-property relationship of Ru-based catalysts is discussed for a better understanding of the Li_(2)O_(2) decomposition mechanism at the cathode interface.Finally,the challenges of Ru-based electrocatalysts are proposed for the future development of Li-O_(2) batteries.
基金the financial support from National Natural Science Foundation of China(Grant no.51472070,51872071)China Postdoctoral Science Foundation(Grant no.172731)。
文摘Rechargeable lithium-oxygen(Li-O2)batteries have appeal to enormous attention because they demonstrate higher energy density than the state-of-the-art Li-ion batteries.Whereas,their practical application is impeded by several challenging problems,such as the low energy round trip efficiencies and the insufficient cycle life,due to the cathode passivation caused by the accumulation of discharge products.Developing efficient catalyst for oxygen reduction and evolution reactions is effective to reduce the overpotentials in Li-O2cells.In our work,we report a Co3O4modified Ag/g-C3N4nanocomposite as a bifunctional cathode catalyst for Li-O2cells.The g-C3N4substrate prevents the accumulation of Ag and Co3O4nanoparticles and the presence of Ag NPs improves the surface area of g-C3N4and electronic conductivity,significantly improving the oxygen reduction/evolution capabilities of Co3O4.Due to a synergetic effect,the Ag/g-C3N4/Co3O4nanocomposite demonstrates a higher catalytic activity than each individual constituent of Co3O4or Ag/g-C3N4for the ORR/OER on as catalysts in Li-O2cells.As a result,the Ag/gC3N4/Co3O4composite shows impressive electrochemical performance in a Li-O2battery,including high discharge capacity,small gap between charge and discharge potential,and high cycling stability.
基金financially supported by the Tsinghua-Foshan Innovation Special Fund(Grant No.2018THFS0409)the China Postdoctoral Science Foundation(Grant No.2019M650668)the National Key Research and Development Program of China(Grant No.2016YFA0201003)。
文摘Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aqueous Li-O_(2)batteries to enhance their discharge capacity and reduce charge overpotential.However,the shuttle effect of RMs in the electrolyte solution usually leads to corrosion of the Li metal anode and uneven Li deposition on the anode surface,resulting in unwanted consumption of electrocatalysts and deterioration of the cells.It is therefore necessary to take some measures to prevent the shuttle effect of RMs and fully utilize the soluble electrocatalysts.Herein,we summarize the strategies to suppress the RM shuttle effect reported in recent years,including electrolyte additives,protective separators and electrode modification.The mechanisms of these strategies are analyzed and their corresponding requirements are discussed.The electrochemical properties of Li-O_(2)batteries with different strategies are summarized and compared.The challenges and perspectives on preventing the shuttle effect of RMs are described for future study.This review provides guidance for achieving shuttle-free redox mediation and for designing Li-O_(2)cells with a long cycle life,high energy efficiency and highly reversible electrochemical reactions.
基金financially supported by the National Natural Science Foundation of China(Grant No.21905033)the Science and Technology Department of Sichuan Province(Grant No.2019YJ0503)the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization(2020P4FZG02A)。
文摘Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries.Herein,oxygen vacancy-rich TiO_(2)(Vo-TiO_(2))nanoparticles(NPs)uniformly dispersing on Ti_(3)C_(2)T_(x)(Vo-TiO_(2)/Ti_(3)C_(2) T_(x))with excellent lithiophilicity feature are presented as effective composite anodes,on which a dense and uniform Li growth behavior is observed.Based on electrochemical studies,mutiphysics simulation and theoretical calculation,it is found that Vo-TiO_(2) coupling with three dimensional(3 D)conductive Ti_(3)C_(2) T_(x) MXene forms highly ordered lithiophilic sites which succeed in guiding Li ions flux and adsorption,thus modulating the uniform Li nucleation and growth.As a result,this composite electrode is capable of preserving Li with high areal capacity of~10 mAh cm^(-2) without the presence of dendrites and large volume expansion.Consequently,the as-prepared Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anode shows outstanding performance including low voltage hysteresis(~19 mV)and superior durability(over 750 h).When assembling with the Vo-TiO_(2)/Ti_(3)C_(2) T_(x)@Li anodes,lithium-oxygen batteries also deliver enhanced cycling stability and improved rate performance.This work demonstrates the effectiveness of oxygen vacancies in guiding Li nucleating and plating behavior at initial stage and brings a promising strategy for promoting the development of advanced Li metal-based batteries.
基金National Research Foundation of Korea,Grant/Award Numbers:2022M3J1A1085410,RS-2023-00208983。
文摘Lithium-oxygen(Li-O_(2))batteries are an emerging energy storage alternative with the potential to meet the recent increase in demand for high-energy-density batteries.From a practical viewpoint,lithium-air(Li-Air)batteries using ambient air instead of pure oxygen could be the final goal.However,the slow oxygen reduction and evolution reactions interfere with reversible cell operation during cycling.Therefore,research continues to explore various catalyst materials.The present study attempts to improve the performance of Li-Air batteries by using porphyrin-based materials known to have catalytic effects in Li-O_(2) batteries.The results confirm that the iron phthalocyanine(FePc)catalyst not only exhibits a catalytic effect in an air atmosphere with a low oxygen fraction but also suppresses electrolyte decomposition by stabilizing superoxide radical ions(O_(2)^(−))at a high voltage range.Density functional theory calculations are used to gain insight into the exact FePc-mediated catalytic mechanism in Li-Air batteries,and various ex situ and in situ analyses reveal the reversible reactions and structural changes in FePc during electrochemical reaction.This study provides a practical solution to ultimately realize an air-breathing battery using nature-friendly catalyst materials.
基金supported by National Natural Science Foundation of China(Nos.52173286,52207249)Major basic research project of Natural Science Foundation of Shandong Province(No.ZR2023ZD12)+1 种基金the State Key Laboratory of Marine Resource Utilization in South China Sea(Hainan University)(No.MRUKF2023013)Open Program of Guangxi Key Laboratory of Information Materials(No.221024-K)。
文摘Highly active cathode catalysts for efficient formation/decomposition of Li_(2)O_(2)are essential for the performance improvement of lithium-oxygen batteries(LOBs).In this study,a grain-refining Co_(0.85)Se catalyst with a lattice spacing of 2.69 A of(101)plane closely matching with the(100)plane(2.72A)of Li_(2)O_(2)was applied for high-performance LOBs.Highly(101)plane exposed Co_(0.85)Se@CNT was synthesized by a simple one-pot hydrothermal method.The Co_(0.85)Se with the lattice matching effect not only led to the efficient conversion and polarized growth of Li_(2)O_(2),but also prevented the formation of byproducts.Density functional theory(DFT)calculations reveal that Co_(0.85)Se(101)plane has the intrinsic catalytic ability to generate/decompose Li_(2)O_(2)during ORR/OER process,due to its homogeneous electron distribution,suitable adsorption energy,and promoted Li_(2)O_(2)growth kinetics.As a consequence,the(101)plane highly exposed Co_(0.85)Se@CNT-80 electrode exhibited remarkable cycle stability over 2400 h at 100 mA/g and 290cycles at 500 mA/g,which is about 2 times longer than other electrodes.
基金supports from the National Key R&D Program of China(No.2019YFA0308000)the National Natural Science Foundation of China(No.21873050)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited density of active sites.Here we present C_(60) as a metal-free cathode catalyst for LOBs,using density functional theory calculations and experimental verifications.The lithiation reactions on the pristine carbon sites of C_(60) are energetically favorable due to its curvedπ-conjugation over the pentagon-hexagon networks.The kinetic analysis specifically reveals low energy barriers for Li_(2)O_(2) decomposition and Li diffusion on C_(60).Consequently,C_(60) exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon nanotubes.Our electrochemical measurements validate the predictions,notably demonstrating that the intrinsic activity of C_(60) is comparable to that of noble metals.
基金supported by a National Research Foundation of Korea(NRF)Grant funded by the Ministry of Science and ICT(2021R1A2C1014294,2022R1A2C3003319)the BK21 FOUR(Fostering Outstanding Universities for Research)through the National Research Foundation(NRF)of Korea.
文摘A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves conductivity.mPR-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain dispersion.Integrating this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 cycles.In situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen reactions.Ex situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability tests.The present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.
基金supported by the National Basic Research Program of China(2014CB932301)the National Natural Science Foundation of China(21473040)Science&Technology Commission of Shanghai Municipality(08DZ2270500)
文摘Li-ion batteries have played a key role in the portable electronics and electrification of transport in modern society. Nevertheless,the limited highest energy density of Li-ion batteries is not sufficient for the long-term needs of society. Since lithium is the lightest metal among all metallic elements and possesses the lowest redox potential of.3.04 V vs. standard hydrogen electrode, it delivers the highest theoretical specific capacity of 3860 mA h g^(-1) and a high working voltage of full batteries which causes a great interest in electrochemical energy storage systems. Lithium-sulfur, lithium-oxygen and corresponding all solid state batteries based on metal lithium anode have received widely attention owing to their high energy densities. However, the problems in the cathode,electrolyte and anode of these three systems restrict their practical application. In this review, the research status and problems of these three energy storage systems are summarized and the challenges and future perspectives are also outlined.
基金supported by the National Natural Science Foundations of China(Nos.21871028,21471020 and 21771024)。
文摘Ti3C2 belongs to MXenes family,which is a new two-dimensional material and has been applied in many fields.With simple method of hydrothermal and high temperature calcination,nano structured Ni/Ti3C2Tx hybrid was synthesized.The stable layer structure of Ti3C2 MXene providing high surface area as well as excellent electronic conductivity are beneficial for deposition and decomposition of discharge product Li2O2.Furthermore,possessing special catalytic activity,Ni nanoparticles with size of about 20 nm could accelerate Li2O2 breaking down.Taking advantage of two kinds of materials,Ni/Ti3C2Tx hybrid as cathode of Li-O2 battery can achieve a maximal specific capacity of 20,264 mAh/g in 100 mA/g and 10,699 mAh/g in 500 mA/g at the first cycle.This work confirms that the prepared Ni/Ti3C2Tx hybrid exhibiting better cycling stability points out a new guideline to improve the electrochemical performance of lithium-oxygen batteries.
基金supported by the National Key R&D Program of China (No.2016YFB0901505)National Natural Science Foundation of China(No. 21573145)
文摘Organic ionic plastic crystals (OIPCs) composed of 1-ethyl-1-methyl pyrrolidinium bis(fluorosulfonyl) imide (P12FSI) and lithium bis(fluorosulfonyl)imide (LiFSI) was used as electrolyte for lithium-oxygen batteries. Since P12FSI-LiFSI electrolyte exhibited high ionic conductivity, good chemical stability and wide electrochemical window, the battery showed good rate capability, excellent cycling stability and can be operated stably for 320 cycles under a fixed capacity of 500 mAh/gcarbon. The use of OIPCs electrolyte could provide a new avenue for the development of high-performance Li-O2 batteries.
基金This study was financially supported by the National Natural Science Foundation of China(grant nos.51771177,51972141,21835002,and 21621001)the 111 Project(no.B17020)+4 种基金the Department of Education of Jilin Province(no.JJKH20190113KJ)the Jilin Province Science and Technology Development Program(grant no.20190303104SF)the Jilin Province/Jilin University Co-construction Project for New Materials(no.SXGJSF2017-3)the Science and Technology Breakthrough Plan of Henan Province(no.202102210242)the Youth Innovation Fund project of Zhengzhou Institute of Technology(no.QNCXJJ2019K2).
文摘Lithium-oxygen(Li-O_(2))batteries have attracted considerable attention due to their high theoretical energy density.However nonrenewable and high-cost electrode materials have limited their progress.Herein,the authors design and fabricate a three-dimensional freestanding bi-biomass egg-sugarcane(Egg-SC)electrode with excellent structure and performance as the cathode for Li-O_(2) batteries.The open,interconnected microchannels derived from the natural SC can provide sufficient pathways for O_(2) gas diffusion.The heteroatom-doped hollow carbon spheres(HD-HCS)obtained via biomass egg supply many of the triphase active sites for the formation and decomposition of the discharge products of Li2O_(2).Benefiting from the unique nature and structure of the cathode,Li-O_(2) batteries show high-rate capacity of 8.07 mAh cm^(-2) and superior cycle stability of 294 cycles at a current density of 0.1 mA cm^(-2).The excellent performance and structure of the bi-biomass cathode possess great application potential in nature-inspired materials design for the cathodes of Li-O_(2) batteries.
基金the National Natural Science Foundation of China(grant nos.51971119 and 52171141)the Natural Science Foundation of Shandong Province(grant nos.ZR2020YQ32 and ZR2020QB122)+2 种基金the China Postdoctoral Science Foundation(grant no.2020M672054)the Guangdong Basic and Applied Basic Research Foundation(grant no.2021A1515111124)the Young Scholars Program of Shandong University(grant no.2019WLJH21).
文摘Developing excellent cathode catalysts with superior catalytic activities is essential for the practical application of aprotic lithium-oxygen batteries(LOBs).Herein,we successfully synthesized nitrogen-doped hollow mesoporous carbon spheres encapsulated with molybdenum disulfide(MoS_(2))nanosheets as the cathode catalyst for rechargeable LOBs,and the relationship between the battery performance and structural characteristics was intensively researched.We found that the synergistic effect of the nitrogen-doped mesoporous carbon and MoS_(2)nanosheets endows superior electrocatalytic activities to the composite catalyst.On the one hand,the nitrogen-doped mesoporous carbon could enable fast charge transfer and effectively accommodate more discharging products in the composite skeleton.On the other hand,the thin MoS_(2)nanosheets could promote mass transportation to facilitate the revisable formation and decomposition of the Li2O2 during oxygen reduction reaction and oxygen evolution reaction,and the side reactions were also prevented,apparently due to their full coverage on the composite surfaces.As a result,the catalytic cathode loaded with 2H-MoS_(2)-modified nitrogen-doped hollow mesoporous carbon spheres exhibited excellent electrochemical performance in terms of large discharge-/charge-specific capacities with low overpotentials and extended cycling life,and they hold great promise for acting as the cathode catalyst for high-performance LOBs.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.U21A2080 and 51788104)Beijing Natural Science Foundation(No.L223008)National Key Research and Development Program of China(No.2022YFB2404403).
文摘Lithium-oxygen(Li-O_(2))batteries have a great potential in energy storage and conversion due to their ultra-high theoretical specific energy,but their applications are hindered by sluggish redox reaction kinetics in the charge/discharge processes.Redox mediators(RMs),as soluble catalysts,are widely used to facilitate the electrochemical processes in the Li-O_(2)batteries.A drawback of RMs is the shuttle effect due to their solubility and mobility,which leads to the corrosion of a Li metal anode and the degradation of the electrochemical performance of the batteries.Herein,we synthesize a polymer-based composite protective separator containing molecular sieves.The nanopores with a diameter of 4Åin the zeolite powder(4A zeolite)are able to physically block the migration of 2,2,6,6-tetramethylpiperidinyloxy(TEMPO)molecules with a larger size;therefore,the shuttle effect of TEMPO is restrained.With the assistance of the zeolite molecular sieves,the cycle life of the Li-O_(2)batteries is significantly extended from~20 to 170 cycles at a current density of 250 mA·g^(-1)and a limited capacity of 500 mAh·g^(-1).Our work provides a highly effective approach to suppress the shuttle effects of RMs and boost the electrochemical performance of Li-O_(2)batteries.
基金financially supported by the National Natural Science Foundation of China (Nos. 21875007 and 22075007)the Beijing Natural Science Foundation (No. JQ19003, KZ201910005002 and L182009)+1 种基金the Project of Youth Talent Plan of Beijing Municipal Education Commission (No. CIT&TCD201804013)the Highgrade discipline construction of Beijing (No. PXM2019–014204–500031)
文摘The polymer electrolyte based lithium-oxygen battery has showed higher safety than that of organic liquid electrolyte.However,the energy efficiency and cycling stability are still the challenges for the practical application of lithium-oxygen battery.Herein,the 1,4 para benzoquinone has been demonstrated as dual-function redox mediator for promoting both oxygen reduction and oxygen evolution reactions of lithium-oxygen battery with polymer electrolyte,which have been confirmed by the Cyclic Voltammetry and discharge/charge test of battery under O_(2) gas,as well as the theoretical calculations.Furthermore,the composite cathode that in-situ constructed by polymerizing electrolyte precursors with redox me-diator can be beneficial for the electrochemical reactions.Combing composite cathode and lithium ions source,the polymer electrolyte based lithium-oxygen batteries can operate for long lifetime with low charge potentials and good rate performances.Thus,this work has highlighted the promising implementation of lithium-oxygen battery based on polymer electrolyte,in which the dual-function redox mediator are employed for both discharge and recharge processes.
基金supported by Ministry of Science and Technology of China (No.2017YFA0206701)National Natural Science Foundation of China (Nos.51822205 and 21875121)China Postdoctoral Science Foundation (No.2019M650045)。
文摘The recent boom in large-scale energy storage system promotes the development of lithium-oxygen batteries because of their high theo retical energy density.However,their applications are still limited by the sluggish kinetic,insoluble discharge product deposition and the undesired parasitic reaction.Herein,the free-standing nitrogen doped reduced graphene oxide/Co(OH)_(2)(NRGO/Co(OH)_(2)) composite films were prepared by a facile hydrothermal method,The NRGO/Co(OH)_(2) composite films display interconnected three-dimensional conductive network,which can not only promote the diffusion of O2 and the transport of electrolyte ions,but also provide abundant storage space for discharge products.Moreover,the introduction of nitrogen-containing functional groups results in improved conductivity and electron adsorption ability,which can facilitate electron transport and enhance the surface catalytic activity.Combining with excellent catalytic performance,the lithium-oxygen batteries with NRGO/Co(OH)_(2) composite film cathodes deliver low charge overpotential and excellent cycling performance.
基金National Natural Science Foundation of China,Grant/Award Number:52002247Natural Science Foundation of Guangdong Province,Grant/Award Number:2019A1515011344。
文摘Aprotic lithium-oxygen(Li-O_(2))batteries represent a promising next-generation energy storage system due to their extremely high theoretical specific capacity compared with all known batteries.Their practical realization is impeded,however,by the sluggish kinetics for the most part,resulting in high overpotential and poor cycling performance.Due to the high catalytic activity and favorable stability of Co-based transition metal oxides,they are regarded as the most likely candidate catalysts,facilitating researchers to solve the sluggish kinetics issue.Herein,this review first presents recent advanced design strategies for Co-based transition metal oxides in Li-O_(2)batteries.Then,the fundamental insights related to the catalytic processes of Co-based transition metal oxides in traditional and novel Li-O_(2)electrochemistry systems are summarized.Finally,we conclude with the current limitations and future development directions of Co-based transition metal oxides,which will contribute to the rational design of catalysts and the practical applications of Li-O_(2)batteries.
