Moderately concentrated electrolyte enabling high-performance lithium metal batteries with a wide working temperature range

The electrolyte integrated with lithium metal anodes is subjected to the issues of interfacial compatibility and stability,which strongly influence the performances of high-energy lithium metal batteries.Here,we report a new electrolyte recipe viz.a moderately concentrated electrolyte comprising of 2.4 M lithium bis(fluorosulfonyl)imide(LiFSI)in a cosolvent mixture of fluorinated ethylene carbonate(FEC)and dimethyl carbonate(DMC)with relatively high ion conductivity.Owing to the preferential decomposition of LiFSI and FEC,an inorganic-rich interphase with abundant Li_(2)O and LiF nanocrystals is formed on lithium metal with improved robustness and ion transfer kinetics,enabling lithium plating/stripping with an extremely low overpotential of~8 mV and the average CE of 97%.When tested in Li||LiFePO_(4) cell,this electrolyte provides long-term cycling with a capacity retention of 98.3%after 1000 cycles at 1 C and an excellent rate performance of 20 C,as well as an areal capacity of 1.35 mA h cm^(-2)at the cathode areal loading of 9 mg cm^(-2).Moreover,the Li||LiFePO_(4) cell exhibits excellent wide-temperature performances(-40~60℃),including long-term cycling stability over 2600 cycles without visible capacity fading at 0℃,as well as extremely high average CEs of 99.6%and 99.8% over 400 cycles under-20℃ and 45℃.

Defect engineering of high-loading single-atom catalysts for electrochemical carbon dioxide reduction

Electrochemical carbon dioxide reduction reaction(CO_(2)RR)provides an attractive approach to carbon capture and utilization for the production high-value-added products.However,CO_(2)RR still suffers from poor selectivity and low current density due to its sluggish kinetics and multitudinous reaction pathways.Single-atom catalysts(SACs)demonstrate outstanding activity,excellent selectivity,and remarkable atom utilization efficiency,which give impetus to the search for electrocatalytic processes aiming at high selectivity.There appears significant activity in the development of efficient SACs for CO_(2)RR,while the density of the atomic sites remains a considerable barrier to be overcome.To construct high-metal-loading SACs,aggregation must be prevented,and thus novel strategies are required.The key to creating high-density atomically dispersed sites is designing enough anchoring sites,normally defects,to stabilize the highly mobile separated metal atoms.In this review,we summarized the advances in developing high-loading SACs through defect engineering,with a focus on the synthesis strategies to achieve high atomic site loading.Finally,the future opportunities and challenges for CO_(2)RR in the area of high-loading single-atom electrocatalysts are also discussed.

Recent progress of surface coating on cathode materials for high-performance lithium-ion batteries

Lithium-ion batteries (LIB) have received substantial attention in the last 10 years,as they offer great promise as power sources that can lead to the electric vehicle (EV) revolution in the next 5 years.Since the cathode serves as a key component in LIB,its properties significantly affect the performance of the whole system.Recently,the cathode surface modification based on coating technique has been widely employed to enhance the electrochemical performances by improving the material conductivity,stabilising the physical structure of materials,as well as preventing the reactions between the electrode and electrolyte.In this work,we reviewed the present of a number of promising cathode materials for Li-ion batteries.After that,we summarized the very recent research progress focusing on the surface coating strategies,mainly including the coating materials,the coating technologies,as well as the corresponding working mechanisms for cathodes.At last,the challenges faced and future guidelines for optimizing cathode materials are discussed.In this study,we propose that the structure of cathode is a crucial factor during the selection of coating materials and technologies.

Lithium metal anodes: Present and future

Commercial lithium-ion(Li-ion)batteries based on graphite anodes are meeting their bottlenecks that are limited energy densities.In order to satisfy the large market demands of smaller and lighter rechargeable batteries,high-capacity metallic Li replacing low-specific-capacity graphite enables the higher energy density in next-generation rechargeable Li metal batteries(LMBs).However,Li metal anode has been suffering from dendritic problems,interfacial side reactions,volume change and low Coulombic efficiency.Therefore,performance enhancements of Li metal anodes are rather important to realize the high energy density characteristic of metallic Li.In this review,the annoying Li dendrite growth,unstable reaction interface and practical application issues of Li metal anodes are summarized and detailedly discussed to understand the current challenges concerning Li metal anodes.For overcoming such remaining challenges,the corresponding strategies and recent advances are covered and categorized.Finally,we discuss future opportunities and perspectives for developing high-performance Li metal anodes.

Recent Advances and Applications Toward Emerging Lithium–Sulfur Batteries:Working Principles and Opportunities

Lithium–sulfur(Li-S)batteries have been considered as promising candidates for large-scale high energy density devices due to the potentially high energy density,low cost,and more pronounced ecological compatibility.However,the complex Li-S conversion reactions,unsatisfactory battery performance,and unsafe metallic Li anode restrict the development of Li-S batteries to achieve commercialization.This review mainly focuses on three aspects which are the remaining challenges,recent advances,and applications in Li-S batteries.Firstly,this review portrays Li-S conversion chemistry involving the multi-step and multi-electron reaction mechanism,as well as the remaining challenges.Then,the scientific strategies and very recent advances of the cathode,electrolyte,lithium anode,and other constituent parts of Li-S batteries are detailly summed up,as well as their advantages and limitations.For the sake of promoting the Li-S batteries practicalization,next section is primarily concerned with problems,the corresponding solutions,and application scenarios of practical pouch cells.Finally,the important findings as guidelines and some future directions as trends for developing emerging Li-S batteries are briefly summarized.

A 3D conducting scaffold with in-situ grown lithiophilic Ni_(2)P nanoarrays for high stability lithium metal anodes

Lithium(Li)metal is the most potential anode material for the next-generation high-energy rechargeable batteries.However,intrinsic surface unevenness and‘hostless’nature of Li metal induces infinite volume effect and uncontrollable dendrite growth.Herein,we design the in-situ grown lithiophilic Ni_(2)P nanoarrays inside nickel foam(PNF).Uniform Ni_(2)P nanoarrays coating presents a very low nucleation overpotential,which induces the homogeneous Li deposition in the entire spaces of three-dimensional(3D)metal framework.Specifically,the lithiophilic Ni_(2)P nanoarrays possess characteristics of electrical conductivity and structural stability,which have almost no expansion and damage during repeating Li plating/stripping.Therefore,they chronically inhibit the growth of Li dendrites.This results in an outstanding Coulombic efficiency(CE)of 98% at 3 mA cm^(-2) and an ultra long cycling life over 2000 cycles with a low overpotential.Consequently,the PNF-Li||LiFePO_(4) battery maintains a capacity retention of 95.3% with a stable CE of 99.9% over 500 cycles at 2 C.

Nomogram for preoperative estimation of liver cirrhosis in hepatitis B virus-related hepatocellular carcinoma patients

Objective:The degree of liver cirrhosis is one of the most important diagnostic and prognostic assessments in chronic liver disease.Among the etiologies of liver cirrhosis,hepatitis B virus(HBV)infection-induced liver damage is most common in Asia-Pacific regions,particularly in China.Many current conventionally used preoperative estimation of liver cirrhosis models.

Novel nomogram model for predicting severe post-hepatectomy liver failure risk in patients with resectable hepatocellular carcinoma

Objective:Currently,liver resection is the most effective curative treatment for patients with resectable hepatocellular carcinoma(HCC).Severe post-hepatectomy liver failure(PHLF)is a serious complication for HCC patients undergoing liver resection.Models have been used to predict severe PHLF in patients with HCC,such as the Child-Pugh score,model for end-stage liver disease(MELD)score.

Neogene integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

The remarkable uplift of the Tibetan Plateau in the Neogene had great impacts on the climate and environment of East Asia and even the world.Therefore,establishment of the Neogene stratigraphic framework of the Tibetan Plateau is of great significance to research in various fields of geosciences.Based on marine sediments,the international chronostratigraphic system of the Neogene is divided into six stages in the Miocene and two stages in the Pliocene.Since the beginning of the Cenozoic,the share of terrestrial strata on continents has increased rapidly.By the Neogene,it had far exceeded that of marine strata,and almost all deposits on the Tibetan Plateau and its surrounding areas were terrestrial strata.In China,the Miocene includes five stages and the Pliocene includes two stages.Except for the Tunggurian of the Miocene,which has a lower boundary at 15 Ma,the other stages have the same paleomagnetic definitions and time intervals as the corresponding international marine stages.Mammalian fossils play a very important role in the division and correlation of Cenozoic terrestrial strata,and rodent,carnivore,proboscidean,perissodactyl and artiodactyl fossils are especially important in Neogene terrestrial biostratigraphy.There are many basins with well-exposed strata and abundant mammalian fossils in the Tibetan Plateau.The lower boundary stratotype sections of the Neogene Xiejian and Bahean stages are located respectively in the Xining and Linxia basins,and there are precise paleomagnetic dates in coordination with mammalian fossils.The lower boundary stratotypes of other stages can also be effectively determined in the Tibetan Plateau.Many first appearing mammalian genera in East Asia also appeared in the Tibetan Plateau and its surrounding areas,especially in the Linxia Basin on the northeast margin and in the Siwaliks on the southwest margin.Among them,Prodeinotherium first appeared at the bottom of the Miocene in the Siwaliks,and the earliest Hipparion of the Old World first appeared at the bottom of the Bahean Stage in the Linxia Basin.Carbon and oxygen isotope analysis of enamel and paleosols of Cenozoic sediments and mammal fossils in the Tibetan Plateau and its surrounding areas have been used to reconstruct the climate,environment and vegetation development characteristics,and revealed that these changes were not only related to global change,but also had regional features.Evidence of the Late Miocene C4plant expansion event based on carbon isotope changes comes from the southern margin of the Tibetan Plateau,but in sharp contrast,δ13C indicates that there was still no clear or significant C4plant signal on the northern margin of the Tibetan Plateau until the end of the Neogene.Theδ18O analysis shows that there were several major climate change events in the Cenozoic,especially in the Late Miocene at about 7 Ma,when positive drift ofδ18O indicates that the northern and southern sides of the Tibetan Plateau were changing to drier environments.The strong uplift of the Tibetan Plateau in the Late Miocene strengthened the thermal contrast between sea and land,which strengthened monsoon circulation and led to the expansion of C4vegetation in South Asia.However,the East Asian summer monsoon,which can bring atmospheric precipitation and a climate suitable for C4plants to northern China,was not enough to affect the northern Tibetan Plateau.The Tibetan Plateau on the whole rose to an altitude of about 3000 m in the Miocene,becoming a barrier to mammalian migration;it reached its modern altitude of more than 4000 m in the Pliocene,thus forming a cryosphere environment,which led to the emergence of ancestral types of the Ice Age fauna.

Constructing a fluorinated interface layer enriched with Ge nanoparticles and Li-Ge alloy for stable lithium metal anodes

Lithium metal batteries(LMBs)based on metallic Li exhibit high energy density to be competent for advanced energy storage applications.However,the unstable solid electrolyte interphase(SEI)layer due to continuous decomposition of electrolytes,and the attendant problem of Li dendrite growth frustrate their commercialization process.Herein,a hybrid SEI comprising abundant LiF,lithiophilic Li-Ge alloy,and Ge nanoparticles is constructed via a simple brush coating method.This fluorinated interface layer with embedded Ge-containing components isolates the Li anode from the corrosive electrolyte and facilitates homogenous Li nucleation as well as uniform growth.Consequently,the modified Li anode exhibits remarkable stability without notorious Li dendrites,delivering stable cycling lives of more than 1000 h for symmetric Li||Li cells and over 600 cycles for Li||Cu cells at 1 mA·cm^(−2).Moreover,the reinforced Li anodes endow multiple full-cell architectures with dramatically improved cyclability under different test conditions.This work provides rational guidance to design an artificial hybrid SEI layer and would stimulate more ideas to solve the dendrite issue and promote the further development of advanced LMBs.

Monsoon boosted radiation of the endemic East Asian carps

Major historical events often trigger the rapid flourishing of a few lineages,which in turn shape established biodiversity patterns.How did this process occur and develop?This study provides a window into this issue.The endemic East Asian carps(EEAC)dominated the ichthyofauna of East Asia and exhibited a high degree of adaptation to monsoonal river-lake ecosystems.A series of evidence,including ecogeography,phylogenetics,and macroevolution,suggests that the EEAC is a lineage that arose with the East Asian monsoon and thrived intimately with subsequent monsoon activities.We further deduce the evolution of the EEAC and find that a range of historical events in the monsoon setting(e.g.,marine transgression and regression and glacial-interglacial cycle)have further reshaped the distribution patterns of EEAC’s members.Comparative genomics analyses reveal that introgressions during the initial period of EEAC radiation and innovations in the regulation of the brain and nervous system may have aided their adaptation to river-lake ecosystems in a monsoon setting,which boosted radiation.Overall,this study strengthens knowledge of the evolutionary patterns of freshwater fishes in East Asia and provides a model case for understanding the impact of major historical events on the evolution of biota.

古近纪/新近纪之交青藏高原陆地生态系统的重大转折

新生代古近纪/新近纪之交是地球生命环境演化史上的重要节点,生物界总体面貌更趋近现代.青藏高原的隆升对该地区的陆地生态系统产生了重大影响,最终形成现代高原冰冻圈环境与生态体系.通过研究近年来高原腹地伦坡拉、尼玛盆地古近纪-新近纪沉积中产出的大量动植物化石,发现青藏高原生态系统在古近纪/新近纪之交经历了由热带、亚热带生态体系向高原型生物群落的重大转折.以上地点渐新世地层中的鱼类、植物和昆虫化石证据表明,高原腹地在26~24 Ma仍为温暖湿润的低地,来自印度洋的暖湿气流还可深入藏北.这一时期动植物以攀鲈和棕榈为代表,不仅反映热带、亚热带气候特征,并且表明当时盆地可能的最大海拔仅有2300 m左右.自中新世开始,高原陆地生态系统整体上向现代型过渡.裂腹鱼开始出现,并自此向特化等级演化,至上新世出现高度特化种类.早中新世植被以北温带落叶阔叶树种占优势,同时出现大量针叶树,草本植物进一步发展,反映气候已具温带特征.哺乳动物在早中新世出现适应温带森林的近无角犀等,而以披毛犀为代表的寒冷适应性冰期动物祖先出现于上新世.青藏高原生态系统这一重大转折与高原主体在早中新世隆升到接近3000 m高度所产生的降温效应相关,同时也受到全球气候转凉的影响.

聚乙二醇/石墨烯复合相变电热膜的制备与性能

文中采用价格低廉的多层石墨烯(MLG)为导电填料,潜热较高的聚乙二醇(PEG)相变材料为基体,通过溶液共混法制备了具有良好电热性能的复合相变电热膜。通过扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射仪(XRD)、差示扫描量热分析(DSC)、热重分析(TGA)、升降温实验等分析了相变电热材料的表面形貌、结构性能、相变焓、热稳定性和电热性能。SEM结果表明,MLG与PEG基体中分散较好,并在PEG中构建了MLG杂化网络,其中MLG提供了导热路径,并限制了PEG在相变过程中的泄漏。FT-IR和XRD结果表明,在制备过程中,PEG与MLG之间没有发生化学反应,但PEG的结晶度有所降低。DSC和TGA分析表明,MLG质量分数为7%时,该复合相变材料相变焓为164J/g,开始热失重温度为300℃左右。升降温实验表明电热膜具有可靠的温度调节性能,3gPEG/MLG(7%)样品在20V电压下可升温至91.3℃,并且能在相变温度65℃附近保温280s以上。

Tibetan Plateau: An evolutionary junction for the history of modern biodiversity

Holding particular biological resources,the Tibetan Plateau is a unique geologic-geographic-biotic interactively unite and hence play an important role in the global biodiversity domain.The Tibetan Plateau has undergone vigorous environmental changes since the Cenozoic,and played roles switching from"a paradise of tropical animals and plants"to"the cradle of Ice Age mammalian fauna".Recent significant paleontological discoveries have refined a big picture of the evolutionary history of biodiversity on that plateau against the backdrop of major environmental changes,and paved the way for the assessment of its far-reaching impact upon the biota around the plateau and even in more remote regions.Here,based on the newly reported fossils from the Tibetan Plateau which include diverse animals and plants,we present a general review of the changing biodiversity on the Tibetan Plateau and its influence in a global scale.We define the Tibetan Plateau as a junction station of the history of modern biodiversity,whose performance can be categorized in the following three patterns:(1)Local origination of endemism;(2)Local origination and"Out of Tibet";(3)Intercontinental dispersal via Tibet.The first pattern is exemplified by the snow carps,the major component of the freshwater fish fauna on the plateau,whose temporal distribution pattern of the fossil schizothoracines approximately mirrors the spatial distribution pattern of their living counterparts.Through ascent with modification,their history reflects the biological responses to the stepwise uplift of the Tibetan Plateau.The second pattern is represented by the dispersal history of some mammals since the Pliocene and some plants.The ancestors of some Ice Age mammals,e.g.,the wholly rhino,Arctic fox,and argali sheep first originated and evolved in the uplifted and frozen Tibet during the Pliocene,and then migrated toward the Arctic regions or even the North American continent at beginning of the Ice Age;the ancestor of pantherines(big cats)first rose in Tibetan Plateau during the Pliocene,followed by the disperse of its descendants to other parts of Asia,Africa,North and South America to play as top predators of the local ecosystems.The early members of some plants,e.g.,Elaeagnaceae appeared in Tibet during the Late Eocene and then dispersed and were widely distributed to other regions.The last pattern is typified by the history of the tree of heaven(Ailanthus)and climbing perch.Ailanthus originated in the Indian subcontinent,then colonized into Tibet after the Indian-Asian plate collision,and dispersed therefrom to East Asia,Europe and even North America.The climbing perches among freshwater fishes probably rose in Southeast Asia during the Middle Eocene,dispersed to Tibet and then migrated into Africa via the docked India.These cases highlight the role of Tibet,which was involved in the continental collision,in the intercontinental biotic interchanges.The three evolutionary patterns above reflect both the history of biodiversity on the plateau and the biological and environmental effects of tectonic uplift.

Into Africa via docked India: a fossil climbing perch from the Oligocene of Tibet helps solve the anabantid biogeographical puzzle

The northward drift of the Indian Plate and its collision with Eurasia have profoundly impacted the evolutionary history of the terrestrial organisms, especially the ones along the Indian Ocean rim. Climbing perches(Anabantidae) are primary freshwater fishes showing a disjunct south Asian-African distribution,but with an elusive paleobiogeographic history due to the lack of fossil evidence. Here, based on an updated time-calibrated anabantiform phylogeny integrating a number of relevant fossils, the divergence between Asian and African climbing perches is estimated to have occurred in the middle Eocene(ca.40 Ma, Ma: million years ago), a time when India had already joined with Eurasia. The key fossil lineage is ?Eoanabas, the oldest anabantid known so far, from the upper Oligocene of the Tibetan Plateau.Ancestral range reconstructions suggest a Southeast Asian origin in the early Eocene(ca. 48 Ma) and subsequent dispersals to Tibet and then India for this group. Thereby we propose their westbound dispersal to Africa via the biotic bridge between India and Africa. If so, climbing perch precursors had probably followed the paleobiogeographical route of snakehead fishes, which have a slightly older divergence between African and Asian taxa. As such, our study echoes some recent molecular analyses in rejecting the previously held ‘‘Gondwana continental drift vicariance" or late Mesozoic dispersal scenarios for the climbing perches, but provides a unique biogeographical model to highlight the role of the preuplift Tibet and the docked India in shaping the disjunct distribution of some air-breathing freshwater fishes around the Indian Ocean.

Pliocene flora and paleoenvironment of Zanda Basin, Tibet, China

This paper describes a plant megafossil assemblage from the Pliocene strata of Xiangzi, Zanda Basin in the western Qinghai-Tibet Plateau. Twenty-one species belonging to 12 genera and 10 families were identified. Studies show that the Pliocene vegetation in Zanda Basin was mostly deciduous shrub composed of Cotoneaster, Spiraea, Caragana, Hippophae,Rhododendron, Potentilla fruticosa, etc. Leaf sizes of these taxa were generally small. Paleoclimate reconstruction using Coexistence Analysis and CLAMP showed that this area had higher temperature and precipitation in the Pliocene than today, and distinct seasonal precipitation variability was established. The reconstructed paleoelevation of Zanda Basin in the Pliocene was similar to modern times. In the context of central Asian aridification, the gradual drought in the area beginning in the late Cenozoic caused vegetation to transition from shrub to desert, and the flora composition also changed.

Air-stable inorganic solid-state electrolytes for high energy density lithium batteries: Challenges, strategies, and prospects

Solid-state batteries have been considered as promising next-generation energy storage devices for potentially higher energy density and better safety compared with commercial lithium-ion batteries that are based on organic liquid electrolytes.However,in terms of indispensable solid-state electrolytes,there are remaining issues to be solved before entering the market.Most solid-state electrolytes are air-sensitive,which causes a complex and expensive cell assembly and impressible interface.Therefore,the solid-state electrolytes are expected to be atmosphere-stable,which will undoubtedly bring significant benefits to solid-state battery manufacturing.This review covers air-stabilityrelated issues of different types of inorganic solid-state electrolytes and the corresponding strategies.First,we provide an overview of solid-state electrolytes and solid-state batteries,including their history and advantages/disadvantages.Then,different types of solid-state electrolytes are selected as examples to illustrate the unfavorable interactions in air and the corresponding adverse effects.Next,according to recent advances,we summarize the effective strategies of constructing different types of air-stable inorganic solid-state electrolytes.Finally,perspectives on designing accessible air-stable solid-state electrolytes are provided,aiming to achieve the assembly of high-performance solid-state batteries in the atmosphere.

The Multiple Modification Road of Li-Rich Manganese-Based Cathode Materials

Li-rich manganese-based cathode materials(LR) are considered as excellent cathode materials for a new generation of lithium-ion batteries causes their outstanding electrochemical performance, friendly price, and environmental friendliness. But defects such as rapid voltage decay and loss of lattice oxygen limit their applications. The electrochemical performance of LR has to be improved by means of modification. The previous single modification methods like element doping, surface coating, structure design, etc. can only optimize the electrochemical performance of LR from one aspect. Recently, multiple modifications,which can combine the advantages of multiple modifications, have been favored by researchers. Here, we comprehensively review the recent progress of multiple modification of LR based on the combination of different modification means. The review and summary of the multiple modification of LR will play a guiding role in its development in the future.

Sulphur-template method for facile manufacturing porous silicon electrodes with enhanced electrochemical performance

Sulphur(S)-template method based on conventional slurry-casting method has been developed to pro-duce porous silicon(Si)electrodes.The facile fabrication technology is suitable for current production line and expected to be widely applied to various electrode materials under large volume change during operation.Specifically,S particles as template agent are mixed with active material Si,carbon conductor and binder forming uniform slurry.After casting and drying,the electrodes are immersed in carbon disul-fide solution to remove S particles rapidly,generating pores in-situ at the original position of S particles.Electrochemical analysis shows that the pores inside electrodes are able to shorten lithium ion diffusion paths,reduce normal expansion rate and decrease formation of cracks in the Si electrode(2 mg_(Si)/cm^(2)),demonstrating a reversible capacity of 951 mAh/g at 0.5 A/g after 100 cycles(with a capacity retention of 99.5%)and a capacity of-826 mAh/g at 2 A/g.