The shuttle effect induced by soluble lithium polysulfides(LiPSs)is known as one of the crucial issues that limit the practical applications of lithium-sulfur(Li-S)batteries.Herein,a titanium dioxide nanoparticle embe...The shuttle effect induced by soluble lithium polysulfides(LiPSs)is known as one of the crucial issues that limit the practical applications of lithium-sulfur(Li-S)batteries.Herein,a titanium dioxide nanoparticle embedded in nitrogen-doped porous carbon nanofiber(TiO_(2)@NCNF)composite is constructed via an interface-induced polymerization strategy to serve as an ideal sulfur host.Under the protection of the nanofiber walls,the uniformly dispersed TiO_(2) nanocrystalline can act as capturing centers to constantly immobilize LiPSs towards durable sulfur chemistry.Besides,the mesoporous microstructure in the fibrous framework endows the TiO_(2)@NCNF host with strong physical reservation for sulfur and LiPSs,sufficient pathways for electron/ion transfer,and excellent endurance for volume change.As expected,the sulfur-loaded TiO_(2)@NCNF composite electrode presents a fabulous rate performance and long cycle lifespan(capacity fading rate of 0.062%per cycle over 500 cycles)at 2.0 C.Furthermore,the assembled Li-S batteries harvest superb areal capacity and cycling stability even under high sulfur loading and lean electrolyte conditions.展开更多
There are growing research interests in developing high-performance energy storage systems to meet the demands for large-scale and sustainable energy storage. The lithium-sulfur （Li-S） batteries have drawn numerous ...There are growing research interests in developing high-performance energy storage systems to meet the demands for large-scale and sustainable energy storage. The lithium-sulfur （Li-S） batteries have drawn numerous attentions due to their exceptionally high energy density compared with other batteries. However, achieving the high capacities with long-term cycle stability and retaining an essentially high sulfur loading remains a tremendous chal- lenge for the designs of Li-S batteries. Graphene is regarded as a very suitable and promising addition to the com- positions for Li-S batteries due to its unique two dimensional （2D） structure, high conductivity and superior me- chanical flexibility. Besides, the functional groups of graphene surface can be tuned flexibly to immobilize the S/Li2Sx on the graphene surface during the cycling process. In this review, the development of graphene-sulfur composites and their applications in Li-S batteries are discussed. The attempts are also devoted to the synthesis approaches of various graphene-based sulfur composites, the graphene-sulfur interaction and the impacts on the elec- trochemical performances as well as the major issues of Li-S batteries.展开更多
The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosh...The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosheets and porous nitrogen-doped carbon(Bi_(2)Se_(3−x)/NC)is prepared by selenizing bismuth metal-organic frameworks as a multifunctional sulfur host.The highly efficient immobilization-conversion on LiPSs is realized by the synergistic effect of structure construction strategy and defect engineering.It is found that Bi_(2)Se_(3−x)with the suitable amount of selenium vacancies achieves the best electrochemical performance due to the advantages of its structure and composition.These results confirm the intrinsic correlation between defects and catalysis,which are revealed by computational and experimental studies.Due to these superiorities,the developed sulfur electrodes exhibited admirable stability and a fairly lower capacity decay rate of approximately 0.0278%per cycle over 1,000 cycles at a 3 C rate.Even at the high sulfur loading of 6.2 mg·cm^(−2),the cathode still demonstrates a high discharge capacity of 455 mAh·g^(−1)at 1 C.This work may enlighten the development of mechanism investigation and design principles regarding sulfur catalysis toward high-performance Li-S batteries.展开更多
Sulfur-host material with abundant pore structure and high catalysis plays an important role in development of high-energy-density lithium-sulfur(Li-S)batteries.Herein,we implanted NiCoP nanoparticles into the N,S co-...Sulfur-host material with abundant pore structure and high catalysis plays an important role in development of high-energy-density lithium-sulfur(Li-S)batteries.Herein,we implanted NiCoP nanoparticles into the N,S co-doped porous carbon derived from petroleum coke(PCPC)to fabricate the sulfur-host of PCPC/NiCoP composites.The high specific surface area of PCPC provides abundant adsorption sites for capturing LiPSs and the NiCoP nanoparticles to improve the polarity and boost the LiPSs conversion kinetics of PCPC.The Li-S cells fabricated with PCPC/NiCoP as sulfur-host deliver high discharge capacity of 1,462.7 mAh·g^(-1)under the current density of 0.1 C and exhibit ultralong lifespan over 800 cycles under the current density of 1,2,and even 5 C.Additionally,the prepared composites cathodes deliver an outstanding discharge capacity of 932.5 and 826.4 mAh·g^(-1)at 0.5 and 1 C with a high sulfur loading of over 3.90 mg·cm^(-2),and remain stable about 60 cycles.Furthermore,the promoted adsorption-conversion process of polysulfides by introducing NiCoP nanoparticles into PCPC was investigated by experimental and theoretical calculation studies.This work offers a new light for tacking the obstacles of porous carbon-based sulfur-host and propelling the development of petroleum coke-based porous carbon for high performance Li-S batteries.展开更多
基金support from the National Natural Science Foundation of China(No.22075042)Shanghai Rising-Star Program(No.22QA1400300)+3 种基金the Natural Science Foundation of Shanghai(No.20ZR1401400)the Shanghai Scientific and Technological Innovation Project(No.22520710100)the Innovation Program of Shanghai Municipal Education Commission(No.2021-01-07-00-03-E00108)the Fundamental Research Funds for the Central Universities,and the Donghua University(DHU)Distinguished Young Professor Program(No.LZB2021002).
文摘The shuttle effect induced by soluble lithium polysulfides(LiPSs)is known as one of the crucial issues that limit the practical applications of lithium-sulfur(Li-S)batteries.Herein,a titanium dioxide nanoparticle embedded in nitrogen-doped porous carbon nanofiber(TiO_(2)@NCNF)composite is constructed via an interface-induced polymerization strategy to serve as an ideal sulfur host.Under the protection of the nanofiber walls,the uniformly dispersed TiO_(2) nanocrystalline can act as capturing centers to constantly immobilize LiPSs towards durable sulfur chemistry.Besides,the mesoporous microstructure in the fibrous framework endows the TiO_(2)@NCNF host with strong physical reservation for sulfur and LiPSs,sufficient pathways for electron/ion transfer,and excellent endurance for volume change.As expected,the sulfur-loaded TiO_(2)@NCNF composite electrode presents a fabulous rate performance and long cycle lifespan(capacity fading rate of 0.062%per cycle over 500 cycles)at 2.0 C.Furthermore,the assembled Li-S batteries harvest superb areal capacity and cycling stability even under high sulfur loading and lean electrolyte conditions.
文摘There are growing research interests in developing high-performance energy storage systems to meet the demands for large-scale and sustainable energy storage. The lithium-sulfur （Li-S） batteries have drawn numerous attentions due to their exceptionally high energy density compared with other batteries. However, achieving the high capacities with long-term cycle stability and retaining an essentially high sulfur loading remains a tremendous chal- lenge for the designs of Li-S batteries. Graphene is regarded as a very suitable and promising addition to the com- positions for Li-S batteries due to its unique two dimensional （2D） structure, high conductivity and superior me- chanical flexibility. Besides, the functional groups of graphene surface can be tuned flexibly to immobilize the S/Li2Sx on the graphene surface during the cycling process. In this review, the development of graphene-sulfur composites and their applications in Li-S batteries are discussed. The attempts are also devoted to the synthesis approaches of various graphene-based sulfur composites, the graphene-sulfur interaction and the impacts on the elec- trochemical performances as well as the major issues of Li-S batteries.
基金the National Natural Science Foundation of China(No.52122702)the Natural Science Foundation of Heilongjiang Province of China(No.JQ2021E005)the Fundamental Research Foundation for Universities of Heilongjiang Province(No.LGYC2018JQ006).
文摘The advancement of lithium-sulfur(Li-S)batteries is severely retarded by lithium polysulfides(LiPSs)shuttling behavior and sluggish redox kinetics.Herein,the heterogeneous composite with defective Bi_(2)Se_(3−x)nanosheets and porous nitrogen-doped carbon(Bi_(2)Se_(3−x)/NC)is prepared by selenizing bismuth metal-organic frameworks as a multifunctional sulfur host.The highly efficient immobilization-conversion on LiPSs is realized by the synergistic effect of structure construction strategy and defect engineering.It is found that Bi_(2)Se_(3−x)with the suitable amount of selenium vacancies achieves the best electrochemical performance due to the advantages of its structure and composition.These results confirm the intrinsic correlation between defects and catalysis,which are revealed by computational and experimental studies.Due to these superiorities,the developed sulfur electrodes exhibited admirable stability and a fairly lower capacity decay rate of approximately 0.0278%per cycle over 1,000 cycles at a 3 C rate.Even at the high sulfur loading of 6.2 mg·cm^(−2),the cathode still demonstrates a high discharge capacity of 455 mAh·g^(−1)at 1 C.This work may enlighten the development of mechanism investigation and design principles regarding sulfur catalysis toward high-performance Li-S batteries.
基金This work was supported by the National Natural Science Foundation of China(No.22071135)Academy of Sciences Large Apparatus United Fund of China(No.U1832187)Natural Science Foundation of Shandong Province(Nos.ZR2019MEM030 and ZR2021ZD05).
文摘Sulfur-host material with abundant pore structure and high catalysis plays an important role in development of high-energy-density lithium-sulfur(Li-S)batteries.Herein,we implanted NiCoP nanoparticles into the N,S co-doped porous carbon derived from petroleum coke(PCPC)to fabricate the sulfur-host of PCPC/NiCoP composites.The high specific surface area of PCPC provides abundant adsorption sites for capturing LiPSs and the NiCoP nanoparticles to improve the polarity and boost the LiPSs conversion kinetics of PCPC.The Li-S cells fabricated with PCPC/NiCoP as sulfur-host deliver high discharge capacity of 1,462.7 mAh·g^(-1)under the current density of 0.1 C and exhibit ultralong lifespan over 800 cycles under the current density of 1,2,and even 5 C.Additionally,the prepared composites cathodes deliver an outstanding discharge capacity of 932.5 and 826.4 mAh·g^(-1)at 0.5 and 1 C with a high sulfur loading of over 3.90 mg·cm^(-2),and remain stable about 60 cycles.Furthermore,the promoted adsorption-conversion process of polysulfides by introducing NiCoP nanoparticles into PCPC was investigated by experimental and theoretical calculation studies.This work offers a new light for tacking the obstacles of porous carbon-based sulfur-host and propelling the development of petroleum coke-based porous carbon for high performance Li-S batteries.
