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
为了满足新一代金属空气电池对绿色、低成本且具有高氧还原催化活性催化剂的迫切需求,本文通过简便方法制备了具有多活性中心的Co3O4-CeO2/Co-N-C(科琴黑)氧还原催化剂.其中,Co3O4和CeO2纳米颗粒均匀地固定在Co、N共掺杂的碳载体表面Co3...为了满足新一代金属空气电池对绿色、低成本且具有高氧还原催化活性催化剂的迫切需求,本文通过简便方法制备了具有多活性中心的Co3O4-CeO2/Co-N-C(科琴黑)氧还原催化剂.其中,Co3O4和CeO2纳米颗粒均匀地固定在Co、N共掺杂的碳载体表面Co3O4-CeO2/Co-N-C在旋转圆盘电极测试中的半波电位与Pt/C接近.以Co3O4-CeO2/Co-N-C作为阴极催化剂的锌空气电池可以在20 mA cm^-2下提供728 mA h g^-1的高比容量并能够维持稳定的放电电压.其优异的催化性能主要归功于Co3O4、CeO2和Co-N-C之间的协同作用、高导电性和大比表面积.Co3O4-CeO2/Co-N-C催化剂具有催化活性高、环境友好、合成工艺简单等优点,在金属空气电池中具有广阔的应用前景.展开更多
Alloy anode with good reversibility of lithium plating/stripping and long cycling stability is considered as promising anode materials.Here,Cu-Sn alloy is used as the substrate for Li deposition to induce the most den...Alloy anode with good reversibility of lithium plating/stripping and long cycling stability is considered as promising anode materials.Here,Cu-Sn alloy is used as the substrate for Li deposition to induce the most densely packed arrangement of Li atoms,thus presenting high lithiophilicity and improving Li plating behaviors.The LiFePO4-based full cell with the asprepared dendrite-free Li metal anode retained at 85 mAh g-1 with a high coulombic efficiency of 99.5% after 300 cycles,presenting a capacity retention of 79.4%.This strategy provides a new perspective to structure dendrite-free Li anode for the next-generation high-energy density batteries.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financial support from the Department of Science and Technology of Guangdong Province,China(2019A050510043)Shenzhen Science and Technology Innovation Commission(JCYJ20180507183818040)。
文摘为了满足新一代金属空气电池对绿色、低成本且具有高氧还原催化活性催化剂的迫切需求,本文通过简便方法制备了具有多活性中心的Co3O4-CeO2/Co-N-C(科琴黑)氧还原催化剂.其中,Co3O4和CeO2纳米颗粒均匀地固定在Co、N共掺杂的碳载体表面Co3O4-CeO2/Co-N-C在旋转圆盘电极测试中的半波电位与Pt/C接近.以Co3O4-CeO2/Co-N-C作为阴极催化剂的锌空气电池可以在20 mA cm^-2下提供728 mA h g^-1的高比容量并能够维持稳定的放电电压.其优异的催化性能主要归功于Co3O4、CeO2和Co-N-C之间的协同作用、高导电性和大比表面积.Co3O4-CeO2/Co-N-C催化剂具有催化活性高、环境友好、合成工艺简单等优点,在金属空气电池中具有广阔的应用前景.
基金financially supported by the National Natural Science Foundation of China(No.21673051)the Department of Science and Technology of Guangdong Province,China(No.2019A050510043)。
文摘Alloy anode with good reversibility of lithium plating/stripping and long cycling stability is considered as promising anode materials.Here,Cu-Sn alloy is used as the substrate for Li deposition to induce the most densely packed arrangement of Li atoms,thus presenting high lithiophilicity and improving Li plating behaviors.The LiFePO4-based full cell with the asprepared dendrite-free Li metal anode retained at 85 mAh g-1 with a high coulombic efficiency of 99.5% after 300 cycles,presenting a capacity retention of 79.4%.This strategy provides a new perspective to structure dendrite-free Li anode for the next-generation high-energy density batteries.
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.
