Lithium metal has aroused extensive research interests as the anode for next-generation rechargeable batteries.However,the well-known dendritic Li growth and consequent safety issues still impair the long-term cycling...Lithium metal has aroused extensive research interests as the anode for next-generation rechargeable batteries.However,the well-known dendritic Li growth and consequent safety issues still impair the long-term cycling performance.Herein,a hybrid structure composed of 3 D carbon cloth and vesicleshaped hollow ZIF-8 modification shell(HZS@CC)was prepared as a smart host for guiding uniform Li deposition.The long-range interconnected 3 D carbon fiber network enables the reduced local current density with homogeneous electrons distribution.Synergistically,abundant surface polar groups and the ultrastructure on ZIF-8 particles effectively guide a well-distributed Li-ions flow to promote the uniform Li nucleation and growth.As a result,stable Li plating/stripping for 2000 h with a low overpotential(≈15 mV)at 1 mA cm^(-2) were achieved in symmetric cells.Coupling with LiFePO_(4) cathode,the full cell delivered long life over 1200 cycles at 6 C.This research demonstrated that a homogenization guiding of Li-ions is of great importance to better make use of the structural advantage of 3 D hosts and achieve improved electrochemical performance.展开更多
Rationally designing sulfur hosts with the functions of confining lithium polysulfides(LiPSs)and promoting sulfur reaction kinetics is critically important to the real implementation of lithium-sulfur(Li-S)batteries.H...Rationally designing sulfur hosts with the functions of confining lithium polysulfides(LiPSs)and promoting sulfur reaction kinetics is critically important to the real implementation of lithium-sulfur(Li-S)batteries.Herein,the defect-rich carbon black(CB)as sulfur host was successfully constructed through a rationally regulated defect engineering.Thus-obtained defect-rich CB can act as an active electrocatalyst to enable the sulfur redox reaction kinetics,which could be regarded as effective inhibitor to alleviate the LiPS shuttle.As expected,the cathode consisting of sulfur and defect-rich CB presents a high rate capacity of 783.8 mA·h·g^−1 at 4 C and a low capacity decay of only 0.07% per cycle at 2 C over 500 cycles,showing favorable electrochemical performances.The strategy in this investigation paves a promising way to the design of active electrocatalysts for realizing commercially viable Li-S batteries.展开更多
Crop rotations are widely used because they can significantly reduce the incidence of pests and diseases.The interactions between non-host roots and pathogens may be key in the inhibition of soilborne pathogens in cro...Crop rotations are widely used because they can significantly reduce the incidence of pests and diseases.The interactions between non-host roots and pathogens may be key in the inhibition of soilborne pathogens in crop rotations.Interactions between fennel(Foeniculum vulgare)roots/root exudates and Phytophthora nicotianae were investigated because of the known allelopathy between fennel and tobacco(Nicotiana tabacum).The effects of the key compounds in the fennel rhizosphere on the mycelial growth and zoospore behavior of P.nicotianae were assessed.The roots of fennel attracted P.nicotianae zoospores and inhibited their motility and the germination of cystospores,with some cystospores rupturing.4-ethylacetophenone,vanillin and N-formylpiperidine were consistently identified in the fennel rhizosphere and were found to interfere with the infection of P.nicotianae,especially vanillin.Hyphae treated with these compounds produced more abnormal branches and accumulated reactive oxygen species.These interspecific interactions between non-host roots and pathogens were found to be an important factor in the inhibition by fennel of infection by P.nicotianae.展开更多
基金financially supported by the National Key Research and Development Program of China(2017YFA0206703)the National Natural Science Foundation of China(21671183)。
文摘Lithium metal has aroused extensive research interests as the anode for next-generation rechargeable batteries.However,the well-known dendritic Li growth and consequent safety issues still impair the long-term cycling performance.Herein,a hybrid structure composed of 3 D carbon cloth and vesicleshaped hollow ZIF-8 modification shell(HZS@CC)was prepared as a smart host for guiding uniform Li deposition.The long-range interconnected 3 D carbon fiber network enables the reduced local current density with homogeneous electrons distribution.Synergistically,abundant surface polar groups and the ultrastructure on ZIF-8 particles effectively guide a well-distributed Li-ions flow to promote the uniform Li nucleation and growth.As a result,stable Li plating/stripping for 2000 h with a low overpotential(≈15 mV)at 1 mA cm^(-2) were achieved in symmetric cells.Coupling with LiFePO_(4) cathode,the full cell delivered long life over 1200 cycles at 6 C.This research demonstrated that a homogenization guiding of Li-ions is of great importance to better make use of the structural advantage of 3 D hosts and achieve improved electrochemical performance.
基金This work was financially supported by the National Key Research and Development Program of China(No.2017YFA0206703)the National Natural Science Foundation of China(No.21671183)the Project of State Key Laboratory of Environment-Friendly Energy Materials(SWUST,Nos.19FKSY16 and 18ZD320304).
文摘Rationally designing sulfur hosts with the functions of confining lithium polysulfides(LiPSs)and promoting sulfur reaction kinetics is critically important to the real implementation of lithium-sulfur(Li-S)batteries.Herein,the defect-rich carbon black(CB)as sulfur host was successfully constructed through a rationally regulated defect engineering.Thus-obtained defect-rich CB can act as an active electrocatalyst to enable the sulfur redox reaction kinetics,which could be regarded as effective inhibitor to alleviate the LiPS shuttle.As expected,the cathode consisting of sulfur and defect-rich CB presents a high rate capacity of 783.8 mA·h·g^−1 at 4 C and a low capacity decay of only 0.07% per cycle at 2 C over 500 cycles,showing favorable electrochemical performances.The strategy in this investigation paves a promising way to the design of active electrocatalysts for realizing commercially viable Li-S batteries.
基金This study was supported by the National Natural Science Foundation of China(31972328,31601682)the Natural Science Foundation of Yunnan Province(2018FG001-046)+3 种基金the Major Program in Yunnan Province(202002AE320012-02-03)the key Yunnan provincial programs of Yunnan Eco-Friendly Food International Cooperation Research Center(2019ZG00901-03)the Yunnan Academician Workstation of Chinese Academy of Engineering(2018IC063)the Program for Innovative Research Team in Science and Technology in University of Yunnan Province.
文摘Crop rotations are widely used because they can significantly reduce the incidence of pests and diseases.The interactions between non-host roots and pathogens may be key in the inhibition of soilborne pathogens in crop rotations.Interactions between fennel(Foeniculum vulgare)roots/root exudates and Phytophthora nicotianae were investigated because of the known allelopathy between fennel and tobacco(Nicotiana tabacum).The effects of the key compounds in the fennel rhizosphere on the mycelial growth and zoospore behavior of P.nicotianae were assessed.The roots of fennel attracted P.nicotianae zoospores and inhibited their motility and the germination of cystospores,with some cystospores rupturing.4-ethylacetophenone,vanillin and N-formylpiperidine were consistently identified in the fennel rhizosphere and were found to interfere with the infection of P.nicotianae,especially vanillin.Hyphae treated with these compounds produced more abnormal branches and accumulated reactive oxygen species.These interspecific interactions between non-host roots and pathogens were found to be an important factor in the inhibition by fennel of infection by P.nicotianae.
