Absorbent Cotton Template Synthesizes Oxygen (sulfide) Nickel/carbon Microtubes And Their Lithium Storage Performance

Nickel-based metal oxides?sulfides?have been considered to be one of the anode candidates for the next generation of lithium-ion batteries because they possess higher theoretical capacity than that of commercial graphite(372 mA h g^-1).However,the large volume change in the process of charge and discharge makes the reversible capacity of this kind of materials decay rapidly,and has poor rate performance and cycle stability.At present,hollow mesoporous hierarchical structures and their carbon matrix composites have shown a good application prospect in lithium storage properties.However,up to now,most of the synthesis methods for such anode materials have relatively complex,and the yield is low.Therefore,the development of simple,low cost,environment-friendly and large-scale synthesis of nickel-based metal oxides?sulfides?as anode materials is still a basic research subject in the further.In this paper,hollow NiO tube,hollow tubular NiO/Ni/C and NiO/GO composite materials,and mesoporous carbon tube co-doped with NiS and N,S?NiS@NSC?were successfully synthesized by simple impregnation of nickel nitrate,different atmosphere sintering or high temperature sulfurization reaction using low-cost and renewable absorbent cotton as a template.The characterization technologies of TG,XRD,SEM,TEM,XPS,BET etc.were used to analyse the composition and microstructure of the above hollow tubular nickel-based materials.And the effects of synthesis conditions,such as adsorption capacity of nickel salt,vulcanization method and sintering temperature,on the phase,morphology and lithium storage properties of the final products were discussed.The results show that NiS@NSC as the anode for lithium ion battery has excellent electrochemical performances,at 0.1 A g^-1,the reversible capacity is still maintained at 715.9 mA h g^-1 after 200 cycles,and even at a high current density of 5 A g^-1,the discharge specific capacity is as high as 411.1 mA h g^-1.As far as we know,NiS@NSC is one of the reported NiS-base anode materials with good rate performance.This work also provides a useful strategy of mesoporous tubular metal sulfides@heteroatom co-doped carbon materials to facile and large-scale synthesis and application in Li-ion battery.