The NiS;nanosheet array on Ni foil(NiS2/NF)was prepared using an in situ growth strategy and sulfidation method and was used as the cathode of lithium sulfur battery.The unique nanostructure of the NiS;nanosheet array...The NiS;nanosheet array on Ni foil(NiS2/NF)was prepared using an in situ growth strategy and sulfidation method and was used as the cathode of lithium sulfur battery.The unique nanostructure of the NiS;nanosheet array can provide abundant active sites for the adsorption and chemical action of polysulfides.Compared with the sulfur powder coated pure NF(pure NF-S)for lithium sulfur battery,the sulfur powder coated NiS_(2)/NF(NiS_(2)/NF-S)electrode exhibits superior electrochemical performance.Specifically,the NiS_(2)/NF-S delivered a high reversible capacity of 1007.5 m Ah g^(-1) at a current density of 0.1 C(1 C=1675 mA g^(-1))and kept 74.5% of the initial capacity at 1.0 C after 200 cycles,indicating the great promise of NiS_(2)/NF-S as the cathode of lithium sulfur battery.In addition,the NiS_(2)/NF-S electrode also showed satisfactory electrochemical performance when used as the cathode for sodium sulfur battery.展开更多
Transition metal oxides have high specific capacity as anode materials for lithium-ion battery.But aggregation of particles and volume expansion during lithiation/delithiation restrict their application.In this work,a...Transition metal oxides have high specific capacity as anode materials for lithium-ion battery.But aggregation of particles and volume expansion during lithiation/delithiation restrict their application.In this work,a three-dimensional hierarchical Ca_(3)Co_(4)O_(9)hollow fiber network assembled by nanosheets is prepared by an electrospinning combined with heat treatment method to overcome these issues and to boost its lithium storage performance.As-synthesized sample possesses excellent cyclic stability(578.6 m A h g^(-1)at 200 m A g^(-1)after 500 cycles)and rate performance(293.5 m A h g^(-1)at 5000 m A g^(-1)),much better than those of commercial Co_(3)O4.Furthermore,the fast kinetics of the three-dimensional Ca_(3)Co_(4)O_(9)hollow fiber network is also confirmed by the variable scan rates CV tests and the EIS measurements,which is dedicated to the specific hierarchical hollow fiber network structure that provides shorter ion transport distances and higher electrical conductivity.This work supplies a universal approach to improve the electrochemical performance of transition metal oxides for lithium ion batteries.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.21673051)the Department of Science and Technology of Guangdong Province,China(Grant No.2019A050510043)。
文摘The NiS;nanosheet array on Ni foil(NiS2/NF)was prepared using an in situ growth strategy and sulfidation method and was used as the cathode of lithium sulfur battery.The unique nanostructure of the NiS;nanosheet array can provide abundant active sites for the adsorption and chemical action of polysulfides.Compared with the sulfur powder coated pure NF(pure NF-S)for lithium sulfur battery,the sulfur powder coated NiS_(2)/NF(NiS_(2)/NF-S)electrode exhibits superior electrochemical performance.Specifically,the NiS_(2)/NF-S delivered a high reversible capacity of 1007.5 m Ah g^(-1) at a current density of 0.1 C(1 C=1675 mA g^(-1))and kept 74.5% of the initial capacity at 1.0 C after 200 cycles,indicating the great promise of NiS_(2)/NF-S as the cathode of lithium sulfur battery.In addition,the NiS_(2)/NF-S electrode also showed satisfactory electrochemical performance when used as the cathode for sodium sulfur battery.
基金the National Natural Science Foundation of China(Grant No.21673051)the Department of Science and Technology of Guangdong Province,China(Grant No.2019A050510043)the financial support from China Scholarship Council。
文摘Transition metal oxides have high specific capacity as anode materials for lithium-ion battery.But aggregation of particles and volume expansion during lithiation/delithiation restrict their application.In this work,a three-dimensional hierarchical Ca_(3)Co_(4)O_(9)hollow fiber network assembled by nanosheets is prepared by an electrospinning combined with heat treatment method to overcome these issues and to boost its lithium storage performance.As-synthesized sample possesses excellent cyclic stability(578.6 m A h g^(-1)at 200 m A g^(-1)after 500 cycles)and rate performance(293.5 m A h g^(-1)at 5000 m A g^(-1)),much better than those of commercial Co_(3)O4.Furthermore,the fast kinetics of the three-dimensional Ca_(3)Co_(4)O_(9)hollow fiber network is also confirmed by the variable scan rates CV tests and the EIS measurements,which is dedicated to the specific hierarchical hollow fiber network structure that provides shorter ion transport distances and higher electrical conductivity.This work supplies a universal approach to improve the electrochemical performance of transition metal oxides for lithium ion batteries.
