Rationalizing the impact of oxygen vacancy on polysulfide conversion kinetics for highly efficient lithium-sulfur batteries

The“shuttle effect”of lithium polysulfides(LiPSs)is a huge challenge for practical use of high-energydensity lithium-sulfur(Li-S)batteries,and one of the main reasons is the sluggish kinetics of sulfur conversion.Metal oxides are able to expedite the sulfur electrochemistry,and the structural defects enhance the adsorption-conversion ability of metal oxides for polysulfides.However,a significant research gap still remains regarding the relationship between the oxygen vacancy concentration and the adsorptivecatalytic performance of metal oxides.Herein,we establish a correlation between oxygen vacancy concentration and adsorptive-catalytic properties by using tungsten oxide(WO_(x))as model catalysts.It is revealed that high-concentration oxygen vacancy is beneficial for enhancing the binding between tungsten oxide and LiPSs,reducing the energy barrier of Li_(2)S decomposition,and promoting polysulfide conversion kinetics.Consequently,the Li-S batteries using the tungsten oxide with high-concentration oxygen vacancies deliver high initial discharge capacity of 1169 mA h g^(-1)at 0.2 C and 865 mA h g^(-1)at 2 C,low attenuation rate of 0.064%per cycle over 1100 cycles at 2 C.With a high sulfur area loading of 5.34 mg cm^(-2),the Li-S batteries still exhibit high initial gravimetric capacity of 982 mA h g^(-1)at 0.1 C and areal capacity of 5.92 mA h cm^(-2).This work promotes the feasibility of defect engineering on metal oxides as an effective mean to enhance the practicality of Li-S batteries.

Two-dimensional silica enhanced solid polymer electrolyte for lithium metal batteries

Solid polymer electrolytes(SPEs)are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal batteries.Polyethylene oxide(PEO)based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility,manufacturability,light weight,and low-cost processing,while they often suffer from low ionic con-ductivity at room temperature,low lithium transference number and unsatisfactory interfacial resis-tance,which largely restrain their practical application.Herein,two-dimensional holey silica nanosheets(2D-HSN)as the fillers,together with LiNO_(3) as the electrolyte additive,are introduced in a PEO/poly(-vinylidene fiuoride-co-hexafluoropropylene)(PVDF-HFP)blended polymer matrix to obtain a SPE.The incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer,thereby facilitating the movement of lithium ions.The HSN-based SPE demonstrates higher ionic conductivity up to 3.7 x 10-4 S cm-1 at 30℃,larger Li+transference number close to 0.34,and more stable lithium plating/stripping than that without the fillers,and HSN can promote the formation of more stable solid electrolyte interphase(SEI)layer.The as-assembled LiFePO4||Li batteries deliver a high specific capacity of 159 mA h g-1 with the capacity retention of 95.5%after 200 cycles at 30℃,as well as superior rate performance and cycling stability compared to that using the blank SPE.

边界理论在组织行为学研究中的应用

技术的发展正在模糊工作和非工作领域之间的界限,人们日常生活中的角色转换变得愈发频繁。边界理论对于探讨个体的微观角色转换具有重要意义。通过文献梳理,本文回顾并归纳了边界理论相关的核心概念和命题,总结了边界理论在组织行为学研究中的主要应用领域:即工作-家庭转换、工作-“第三地”转换和工作领域内转换,并讨论了其在实际应用中的两个重要启示:角色过度分割和角色过度整合这两种边界管理策略各自存在的潜在危害。最后提出未来可以深入开展工作-家庭微边界研究、线上边界管理研究、工作-社交转换研究、中国情境下的边界理论研究以及长期-短期导向文化价值观下的个体角色边界管理研究,来拓展边界理论在组织行为学中的应用。

GOLM1 restricts colitis and colon tumorigenesis by ensuring Notch signaling equilibrium in intestinal homeostasis

Intestinal epithelium serves as the first barrier against the infections and injuries that mediate colonic inflammation.Colorectal cancer is often accompanied with chronic inflammation.Differed from its well-known oncogenic role in many malignancies,we present here that Golgi membrane protein 1(G0LM1,also referred to as GP73)suppresses colorectal tumorigenesis via maintenance of intestinal epithelial barrier.G0LM1 deficiency in mice conferred susceptibility to mucosal inflammation and colitis-induced epithelial damage,which consequently promoted colon cancer.Mechanistically,depletion of G0LM1 in intestinal epithelial cells(lECs)led to aberrant Notch activation that interfered with IEC differentiation,maturation,and lineage commitment in mice.Pharmacological inhibition of Notch pathway alleviated epithelial lesions and restrained pro-tumorigenic inflammation in G0LM1-deficient mice.Therefore,G0LM1 maintains IEC homeostasis and protects against colitis and colon tumorigenesis by modulating the equilibrium of Notch signaling pathway.