The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited ...The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited the applications of Li-S batteries.In this study,we report a rational strategy to accelerate the polysulfide catalysis via constructing phosphorus modulated porous CeO_(2)(P-CeO_(2))for advanced Li-S batteries.The morphology and surface analysis demonstrate that the P-CeO_(2)consists of abundant Pmodulated porous CeO_(2)nanocrystallines.The battery performance reveals that the introduction of P will lead to an improved initial capacity of 1027 mA hg^(-1)than that of bare CeO_(2)(895.7 mA hg^(-1))at 0.2 C.In addition,the P-CeO_(2)cathode can maintain a low capacity decay ratio of 0.10%per cycle after 500 cycles at 1.0 C.The coin battery tests suggest that the P-CeO_(2)cathode presents faster oxidation-reduction kinetics of LiPS and quick diffusion of Li^+ions.Meanwhile,the studies of redox processes and chemical interactions of LiPS have demonstrated the P-CeO_(2)cathode displays stronger adsorption of Li_(2)S_(6),higher redox peak current,and earlier precipitation of Li_(2)S than the bare CeO_(2).This study demonstrates for the first time that the P-modulation of metal oxide surface can simultaneously promote the catalytic reaction kinetics and chemical interaction of LiPS.We anticipate that this P-modulation method can be extended to many other nanostructured metal catalytic sites for developing affordable advanced Li-S batteries.展开更多
基金financially supported by the National Key R&D Program of China(2021YFE0205000)the National Natural Science Foundation of China(No.52173133)+5 种基金the Science and Technology Project of Sichuan Province(Nos.2021YFH0135 and 2020YFH0087)the China Postdoctoral Science Foundation(2021M692303)the full-time Postdoctoral Foundation of Sichuan University(2021SCU12013)the support of the State Key Laboratory of Polymer Materials Engineering(No.sklpme 2021-4-02)the Fundamental Research Funds for the Central Universitiesthe Alexander von Humboldt Fellowship。
文摘The insulating nature of sulfur species,sluggish reaction kinetics,and uncontrolled dissolution of lithium polysulfide(LiPS)intermediates during the complex and multiphase sulfur redox process,have severely inhibited the applications of Li-S batteries.In this study,we report a rational strategy to accelerate the polysulfide catalysis via constructing phosphorus modulated porous CeO_(2)(P-CeO_(2))for advanced Li-S batteries.The morphology and surface analysis demonstrate that the P-CeO_(2)consists of abundant Pmodulated porous CeO_(2)nanocrystallines.The battery performance reveals that the introduction of P will lead to an improved initial capacity of 1027 mA hg^(-1)than that of bare CeO_(2)(895.7 mA hg^(-1))at 0.2 C.In addition,the P-CeO_(2)cathode can maintain a low capacity decay ratio of 0.10%per cycle after 500 cycles at 1.0 C.The coin battery tests suggest that the P-CeO_(2)cathode presents faster oxidation-reduction kinetics of LiPS and quick diffusion of Li^+ions.Meanwhile,the studies of redox processes and chemical interactions of LiPS have demonstrated the P-CeO_(2)cathode displays stronger adsorption of Li_(2)S_(6),higher redox peak current,and earlier precipitation of Li_(2)S than the bare CeO_(2).This study demonstrates for the first time that the P-modulation of metal oxide surface can simultaneously promote the catalytic reaction kinetics and chemical interaction of LiPS.We anticipate that this P-modulation method can be extended to many other nanostructured metal catalytic sites for developing affordable advanced Li-S batteries.