Lithium-sulfur batteries(LSBs)are one of the main candidates for the next generation of energy storage systems.To improve the performance of LSBs,we herein propose the use of strained MoS_(2)(s-MoS_(2))as a catalytica...Lithium-sulfur batteries(LSBs)are one of the main candidates for the next generation of energy storage systems.To improve the performance of LSBs,we herein propose the use of strained MoS_(2)(s-MoS_(2))as a catalytically active sulfur host.The introduction of strain in the MoS_(2)surface,which alters its atomic positions and expands the S-Mo-S angle,shifts the d-band center closer to the Fermi level and provides the surface with abundant and highly active catalytic sites;these enhance the catalyst's ability to adsorb lithium polysulfides(LiPS),accelerating its catalytic conversion and promoting lithium-ion transferability.Strain is generated through the synthesis of core-shell nanoparticles,using different metal sulfides as strain-inducing cores.s-MoS_(2)nanoparticles are supported on carbon nanofibers(CNF/s-MoS_(2)),and the resulting electrodes are characterized by capacities of 1290 and 657 mAh g−1 at 0.2 and 5 C,respectively,with a 0.05%capacity decay rate per cycle at 8 C during 700 cycles.Overall,this work not only provides an ingenious and effective strategy to regulate LiPS adsorption and conversion through strain engineering,but also indicates a path toward the application of strain engineering in other energy storage and conversion fields.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.:11674140 and 21975123)partially by the Fundamental Research Funds for the Central Universities(Grant Nos.:lzujbky-2021-it33).C.Y.Zhang,C.Q.Zhang,and C.H.Li thank the China Scholarship Council for the scholarship support.The authors also greatly acknowledge the support supported by the Supercomputing Center of Lanzhou University,China.
文摘Lithium-sulfur batteries(LSBs)are one of the main candidates for the next generation of energy storage systems.To improve the performance of LSBs,we herein propose the use of strained MoS_(2)(s-MoS_(2))as a catalytically active sulfur host.The introduction of strain in the MoS_(2)surface,which alters its atomic positions and expands the S-Mo-S angle,shifts the d-band center closer to the Fermi level and provides the surface with abundant and highly active catalytic sites;these enhance the catalyst's ability to adsorb lithium polysulfides(LiPS),accelerating its catalytic conversion and promoting lithium-ion transferability.Strain is generated through the synthesis of core-shell nanoparticles,using different metal sulfides as strain-inducing cores.s-MoS_(2)nanoparticles are supported on carbon nanofibers(CNF/s-MoS_(2)),and the resulting electrodes are characterized by capacities of 1290 and 657 mAh g−1 at 0.2 and 5 C,respectively,with a 0.05%capacity decay rate per cycle at 8 C during 700 cycles.Overall,this work not only provides an ingenious and effective strategy to regulate LiPS adsorption and conversion through strain engineering,but also indicates a path toward the application of strain engineering in other energy storage and conversion fields.
