以Li_2CO_3,锐钛矿纳米TiO_2为原料采用高温固相法合成了微米级Li_4Ti_5O_(12)负极材料,并将其与葡萄糖、Ag NO3复合,制备出了C+Ag表面修饰的C+Ag/Li_4Ti_5O_(12)复合材料。借助XRD、SEM、电化学工作站和充放电测试仪表征C+Ag/Li_4Ti_5O...以Li_2CO_3,锐钛矿纳米TiO_2为原料采用高温固相法合成了微米级Li_4Ti_5O_(12)负极材料,并将其与葡萄糖、Ag NO3复合,制备出了C+Ag表面修饰的C+Ag/Li_4Ti_5O_(12)复合材料。借助XRD、SEM、电化学工作站和充放电测试仪表征C+Ag/Li_4Ti_5O_(12)材料的物理性能和电化学性能。结果表明:C+Ag表面修饰的Li_4Ti_5O_(12)复合材料有效提升了Li_4Ti_5O_(12)的电化学性能。0.1 C首次放电比容量为165.8 m Ah/g,5 C放电比容量仍可达到80 m Ah/g。展开更多
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
文摘以Li_2CO_3,锐钛矿纳米TiO_2为原料采用高温固相法合成了微米级Li_4Ti_5O_(12)负极材料,并将其与葡萄糖、Ag NO3复合,制备出了C+Ag表面修饰的C+Ag/Li_4Ti_5O_(12)复合材料。借助XRD、SEM、电化学工作站和充放电测试仪表征C+Ag/Li_4Ti_5O_(12)材料的物理性能和电化学性能。结果表明:C+Ag表面修饰的Li_4Ti_5O_(12)复合材料有效提升了Li_4Ti_5O_(12)的电化学性能。0.1 C首次放电比容量为165.8 m Ah/g,5 C放电比容量仍可达到80 m Ah/g。
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.
