Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation st...Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation strategy to construct threedimensional(3D)Co-MoS2 nanoflowers with tailorable 1T/2H phase and interlayer distance.The as-formed S-Co-S covalent bonds serve as“electric bridges”to accelerate interlayer charge transfer without 1T phase degeneration during sodiation and desodiation.Quantum density functional theory(QDFT)calculations further confirm that the optimal Co-MoS2 nanoflowers possess the highest Na adsorption energy with reduced ionic diffusion barrier.Consequently,they deliver a superior sodiumstorage capacity of 351 mAh g−1 in 0.4-3.0 V even at 20 A g−1 without capacity fading at 5 A g−1 for 2000 cycles.The high electrochemical reversibility of the 1T phase in Co-MoS2,which accounts for such excellent performance,has been unveiled for the first time by in situ Raman spectra.This finding demonstrates important insights onto promoting two-dimensional(2D)nanomaterials toward rapid charging alkali-ion batteries.展开更多
基金This study was supported by the National Natural Science Foundation of China(nos.51672082,21975074,and 91534202)the Basic Research Program of Shanghai(no.17JC1402300)+1 种基金the Shanghai Scientific and Technological Innovation Project(no.18JC1410500)the National Program for Support of Top-Notch Young Professionals,and the Fundamental Research Funds for the Central Universities(no.222201718002).
文摘Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation strategy to construct threedimensional(3D)Co-MoS2 nanoflowers with tailorable 1T/2H phase and interlayer distance.The as-formed S-Co-S covalent bonds serve as“electric bridges”to accelerate interlayer charge transfer without 1T phase degeneration during sodiation and desodiation.Quantum density functional theory(QDFT)calculations further confirm that the optimal Co-MoS2 nanoflowers possess the highest Na adsorption energy with reduced ionic diffusion barrier.Consequently,they deliver a superior sodiumstorage capacity of 351 mAh g−1 in 0.4-3.0 V even at 20 A g−1 without capacity fading at 5 A g−1 for 2000 cycles.The high electrochemical reversibility of the 1T phase in Co-MoS2,which accounts for such excellent performance,has been unveiled for the first time by in situ Raman spectra.This finding demonstrates important insights onto promoting two-dimensional(2D)nanomaterials toward rapid charging alkali-ion batteries.