The practical applications of lithium-sulfur(Li-S)battery have been greatly hindered by the severe polysulfide shuttle at the cathode and rampant lithium dendrite growth at the anode.One of the effective solutions dea...The practical applications of lithium-sulfur(Li-S)battery have been greatly hindered by the severe polysulfide shuttle at the cathode and rampant lithium dendrite growth at the anode.One of the effective solutions deals with concurrent management of both electrodes.Nevertheless,this direction remains in a nascent stage due to a lack of material selection and mechanism exploration.Herein,we devise a temperature-mediated direct chemical vapor deposition strategy to realize the controllable synthesis of three-dimensional boron/nitrogen dual-doped graphene(BNG)particulated architectures,which is employed as a light-weighted and multi-functional mediator for both electrodes in Li-S batteries.Benefiting from the“sulfiphilic”and“lithiophilic”features,the BNG modified separator not only enables boosted kinetics of polysulfide transformation to mitigate the shuttle effect but also endows uniform lithium deposition to suppress the dendritic growth.Theoretical calculations in combination with electro-kinetic tests and operando Raman analysis further elucidate the favorable sulfur and lithium electrochemistry of BNG at a molecular level.This work offers direct insight into the mediator design via controllable synthesis of graphene materials to tackle the fundamental challenges of Li-S batteries.展开更多
A sort of lightwerght porous ceramic foam ball that can float on the water was recently made from the nat- ural zeolite. The diameters of porous hall and its macroscopic pores are around 5 and 1 mm, respectively. Such...A sort of lightwerght porous ceramic foam ball that can float on the water was recently made from the nat- ural zeolite. The diameters of porous hall and its macroscopic pores are around 5 and 1 mm, respectively. Such ball surface could be modified to activate in different ways, i. e. loading the active alumina or desili- cating the ball. Both of modified products have been investigated to adsorb the toxic ion of arsenic （As） in water effectively. This kind of porous ceramic hall was prepared by powder sintering, using natural clinop- tilolite powder as the primary raw material. An active-alumina loaded porous ceramic product was genera- ted by sol-gel method with pseudoboehmite （A1OOH） as the main composition. The active AI atom on the porous ball surface could also be achieved by desilicating the ceramic ball in the NaOH solution. Such a desilicated product exhibited a good activity to adsorb the arsenic ion although carrying no ac- tive alumina. With this effective porous structure, the present products can be expected to become practically advantageous.展开更多
基金financially supported by the National Natural Science Foundation of China(51702225)the National Key Research and Development Program(2019YFA0708201)+3 种基金the Beijing Municipal Science and Technology Commission(Z161100002116020)the China Postdoctoral Science Foundation funded project(2020 M681704,2021 T140493)the support from Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,Suzhou,Chinathe support from the Postdoctoral Research Foundation of Jiangsu Province。
文摘The practical applications of lithium-sulfur(Li-S)battery have been greatly hindered by the severe polysulfide shuttle at the cathode and rampant lithium dendrite growth at the anode.One of the effective solutions deals with concurrent management of both electrodes.Nevertheless,this direction remains in a nascent stage due to a lack of material selection and mechanism exploration.Herein,we devise a temperature-mediated direct chemical vapor deposition strategy to realize the controllable synthesis of three-dimensional boron/nitrogen dual-doped graphene(BNG)particulated architectures,which is employed as a light-weighted and multi-functional mediator for both electrodes in Li-S batteries.Benefiting from the“sulfiphilic”and“lithiophilic”features,the BNG modified separator not only enables boosted kinetics of polysulfide transformation to mitigate the shuttle effect but also endows uniform lithium deposition to suppress the dendritic growth.Theoretical calculations in combination with electro-kinetic tests and operando Raman analysis further elucidate the favorable sulfur and lithium electrochemistry of BNG at a molecular level.This work offers direct insight into the mediator design via controllable synthesis of graphene materials to tackle the fundamental challenges of Li-S batteries.
基金supported by the Testing Foundation of Beijing Normal University(No.C16)
文摘A sort of lightwerght porous ceramic foam ball that can float on the water was recently made from the nat- ural zeolite. The diameters of porous hall and its macroscopic pores are around 5 and 1 mm, respectively. Such ball surface could be modified to activate in different ways, i. e. loading the active alumina or desili- cating the ball. Both of modified products have been investigated to adsorb the toxic ion of arsenic （As） in water effectively. This kind of porous ceramic hall was prepared by powder sintering, using natural clinop- tilolite powder as the primary raw material. An active-alumina loaded porous ceramic product was genera- ted by sol-gel method with pseudoboehmite （A1OOH） as the main composition. The active AI atom on the porous ball surface could also be achieved by desilicating the ceramic ball in the NaOH solution. Such a desilicated product exhibited a good activity to adsorb the arsenic ion although carrying no ac- tive alumina. With this effective porous structure, the present products can be expected to become practically advantageous.
