【摘 要】
：
Potassium-ion batteries (KIBs) have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low cost.However,previous reports focused on the intercalation-type cathode materials usual
【机 构】
：
College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 4100
论文部分内容阅读
Potassium-ion batteries (KIBs) have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low cost.However,previous reports focused on the intercalation-type cathode materials usually showed an inferior capacity,together with a poor cyclic life caused by the repetitive intercalation of large-size K-ions,which hinders their practical application.Here,we combine the strategies of carbon coating,template etching and hydrothermal selenization to prepare yolk-shelled FeSe2@N-doped carbon nanoboxes (FeSe2@C NBs),where the inner highly-crystalline FeSe2 clusters are completely surrounded by the self-supported carbon shell.The integrated and highly conductive carbon shell not only provides a fast electron/ion diffusion channel,but also prevents the agglomeration of FeSe2 clusters.When evaluated as a conversion-type cathode material for KIBs,the FeSe2@C NBs electrode delivers a relatively high specific capacity of 257 mAh/g at 100 mA/g and potential platform of about 1.6V,which endow a high energy density of about 411 Wh/kg.Most importantly,by designing a robust host with large internal void space to accommodate the volumetric variation of the inner FeSe2 clusters,the battery based on FeSe2@C NBs exhibits ultra-long cycle stability.Specifically,even after 700 cycles at 100 mA/g,a capacity of 221 mAh/g along with an average fading rate of only 0.02％ can be retained,which achieves the optimal balance of high specific capacity and long-cycle stability.
其他文献
Although transition metal phospho-sulfides deliver outstanding electrochemical performance,complex preparation methods hindered their further development.Herein,we report a facile one-step electrodeposition approach to deposit interconnected nanowalls-lik
The angle dependence of photonic crystals (PCs) dramatically limits their practical applications in the colorimetrical sensing of humidity and volatile organic compound (VOC) vapors.In addition,it is challenging for inverse opal PCs to colorimetrically di
Surface oxidized iron-nickel nanorods coupling with reduced graphene architectures (FeNi-O-rGA) are successfully constructed via hydrothermal,freeze-drying,and thermal activation approaches.The hierarchical structure can provide lots of pathways for fast
The trade-off between the electrochemical performance and mechanical strength is still a challenge for Ti3C2Tx free-standing electrode.Herein,a facile approach was proposed to fabricate a Microfibrillated cellulose@Ti3C2Tx (MFC@Ti3C2Tx) self-assembled mic
Na3V2(PO4)3 is a very prospective sodium-ion batteries (SIBs) electrode material owing to its NASICON structure and high reversible capacity.Conversely,on account of its intrinsic poor electronic conductivity,Na3V2(PO4)3 electrode materials confront with
In this paper,a hydrothermal approach is utilized for the first time in integrating graphene oxide (GO),acetic acid (HAc) and nickel foam to prepare hydrogenated graphene (HG).There are two primary aims of this study:one is to ascertain the structure of t
Crystalline engineering and heterostructure have attracted much attention as effective strategies to improve the electrocatalytic activity for hydrogen evolution reaction (HER).In this study,a new heterostructure catalyst (Ru/RuS2@N-rGO) with low crystall
健康长寿是人类一直追求的目标,作为复杂的生物学现象,其与复杂的遗传和环境因素的联合作用密切相关.我国老龄化形势严峻,长寿而不健康的问题依然突出.近年来,我国相关研究机构针对健康长寿的关键影响因素进行了研究,取得了一定进展.本文阐述中国健康长寿纵向调查队列(CLHLS)、广西自然长寿队列、海南自然长寿人群等主要的健康长寿人群资源,综述我国科学挖掘的影响人群健康长寿的遗传基因、长链非编码RNA及甲基化表观遗传修饰和线粒体含量等领域的最新进展,并针对性别、社会、心理健康、营养、肠道菌群等研究热点与健康长寿的关系
衰老是有机体各项生理机能随着时间发生变化的过程.在衰老过程中神经系统功能下降是造成感觉、运动和认知等行为退化的重要原因.本文介绍我国衰老的神经生物学领域取得的重要研究成果,并就神经系统信号和机体寿命调控、神经系统衰老和行为退化、神经系统衰老的生物学机制和延缓神经系统衰老的相关研究进行总结和展望.
阿尔茨海默病(Alzheimer\'s?Disease,?AD)是影响老年人群健康的重大疾病,给家庭和社会造成了沉重的负担.然而目前对AD的发生机制缺乏足够了解,临床防治困难.本文基于近年来的研究进展,从衰老角度探讨AD的发生机制和防治策略,包括衰老对大脑功能的影响、衰老促进AD发生的作用机制、以衰老为干预靶点的AD防治策略,并对我国AD研究提出建议.