The intrinsic sluggish conversion kinetics and severe shuttle effect in lithium-sulfur(Li-S)batteries are responsible for their poor reversible capacity and cycling longevity,which have greatly hindered their practica...The intrinsic sluggish conversion kinetics and severe shuttle effect in lithium-sulfur(Li-S)batteries are responsible for their poor reversible capacity and cycling longevity,which have greatly hindered their practical applications.To address these drawbacks,herein,we design and construct a heterostructured Ni/Ni_(2)P embedded in a mesoporous carbon nanosphere composite(Ni/Ni_(2)P-MCN)for boosting polysulfide catalytic conversion in Li-S batteries.The Ni/Ni_(2)PMCN-modified separator could not only prevent the shuttle effect significantly through abundant chemical adsorptive sites,but also demonstrate superior catalytic reactivities for the conversion of polysulfides.More importantly,the conductive carbon matrix with an exposed mesoporous structure can serve as an effective physical barrier to accommodate deposited insoluble Li_(2)S.Consequently,the cells with the Ni/Ni_(2)P-MCN-modified separator exhibit greatly boosted rate capability(431 mA h g^(-1) at 5 C)and cycling stability(a capacity decay of 0.031% per cycle after 1500 cycles).Even at an enhanced sulfur loading of 4.2 mg cm^(-2),a stable and superior areal capacity(about 3.5 mA h cm^(-2))has been demonstrated.We envision that the unique Ni/Ni_(2)P heterostructure in the porous carbon matrix could offer great potential for highperformance and sustained energy storage devices.展开更多
基金financially supported by the National Natural Science Foundation of China(52072124)Shanghai Municipal Science and Technology Major Project(2018SHZDZX03)+3 种基金the Natural Science Foundation of Shanghai(20ZR1414900)the Leading Talents in Shanghai in2018the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe 111 Project(B14018)。
文摘The intrinsic sluggish conversion kinetics and severe shuttle effect in lithium-sulfur(Li-S)batteries are responsible for their poor reversible capacity and cycling longevity,which have greatly hindered their practical applications.To address these drawbacks,herein,we design and construct a heterostructured Ni/Ni_(2)P embedded in a mesoporous carbon nanosphere composite(Ni/Ni_(2)P-MCN)for boosting polysulfide catalytic conversion in Li-S batteries.The Ni/Ni_(2)PMCN-modified separator could not only prevent the shuttle effect significantly through abundant chemical adsorptive sites,but also demonstrate superior catalytic reactivities for the conversion of polysulfides.More importantly,the conductive carbon matrix with an exposed mesoporous structure can serve as an effective physical barrier to accommodate deposited insoluble Li_(2)S.Consequently,the cells with the Ni/Ni_(2)P-MCN-modified separator exhibit greatly boosted rate capability(431 mA h g^(-1) at 5 C)and cycling stability(a capacity decay of 0.031% per cycle after 1500 cycles).Even at an enhanced sulfur loading of 4.2 mg cm^(-2),a stable and superior areal capacity(about 3.5 mA h cm^(-2))has been demonstrated.We envision that the unique Ni/Ni_(2)P heterostructure in the porous carbon matrix could offer great potential for highperformance and sustained energy storage devices.