A high sulfur content sulfur–carbon composite was synthesized via in situ generation method in aqueous solution.When the sulfur loading is up to 90%,the electrode still exhibits good cycling performance with a revers...A high sulfur content sulfur–carbon composite was synthesized via in situ generation method in aqueous solution.When the sulfur loading is up to 90%,the electrode still exhibits good cycling performance with a reversible capacity of about 623 mAh·g^(-1)after 100 cycles.To further commercialize the Li–S battery,understanding the capacity degradation mechanism is very essential,especially with a high sulfur loading electrode.To achieve this goal,the electrochemical performance of the high sulfur loading electrode was studied,and the structure change of the electrode after cycling was also examined by ex situ scanning electron microscopy(SEM)and other techniques.The result shows that the Li_(2)S_(2)and Li_(2)S inhomogeneous precipitation contributes to the majority capacity fading of the high sulfur loading Li–S cells.展开更多
Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as p...Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as precursor. The unique and delicate structure where three-dimensional interconnected bacterial cellulose（BC） network embedded in two-dimensional GO skeleton could not only work as an effective barrier to retard polysulfide diffusion during the charge/discharge process to enhance the cyclic stability of the Li–S battery, but also offer a continuous electron transport pathway for the improved rate capability.As a result, by utilizing pure sulfur as cathodes, the Li–S batteries assembled with PBC/GO interlayer can still exhibit a capacity of nearly 600 mAh·g^-1 at 3C and only 0.055% capacity decay per cycle can be observed over 200 cycles. Additionally, the cost-efficient and environmentfriendly raw materials may enable the PBC/GO sandwich interlayer to be an advanced configuration for Li–S batteries.展开更多
基金financially supported by the Beijing Municipal Science and Technology Project (No.Z171100000917021)。
文摘A high sulfur content sulfur–carbon composite was synthesized via in situ generation method in aqueous solution.When the sulfur loading is up to 90%,the electrode still exhibits good cycling performance with a reversible capacity of about 623 mAh·g^(-1)after 100 cycles.To further commercialize the Li–S battery,understanding the capacity degradation mechanism is very essential,especially with a high sulfur loading electrode.To achieve this goal,the electrochemical performance of the high sulfur loading electrode was studied,and the structure change of the electrode after cycling was also examined by ex situ scanning electron microscopy(SEM)and other techniques.The result shows that the Li_(2)S_(2)and Li_(2)S inhomogeneous precipitation contributes to the majority capacity fading of the high sulfur loading Li–S cells.
基金financially supported by the Ministry of Science and Technology of China(No.2012CB933403)the National Natural Science Foundation of China(Nos.51425302 and 51302045)the Beijing Municipal Science and Technology Commission(No.Z121100006812003)
文摘Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as precursor. The unique and delicate structure where three-dimensional interconnected bacterial cellulose（BC） network embedded in two-dimensional GO skeleton could not only work as an effective barrier to retard polysulfide diffusion during the charge/discharge process to enhance the cyclic stability of the Li–S battery, but also offer a continuous electron transport pathway for the improved rate capability.As a result, by utilizing pure sulfur as cathodes, the Li–S batteries assembled with PBC/GO interlayer can still exhibit a capacity of nearly 600 mAh·g^-1 at 3C and only 0.055% capacity decay per cycle can be observed over 200 cycles. Additionally, the cost-efficient and environmentfriendly raw materials may enable the PBC/GO sandwich interlayer to be an advanced configuration for Li–S batteries.
