The exceptional mechanical and electrical nature of grapheme makes it a viable candidate for enhancing the effectiveness of electrode material. In recent years, Graphene based SiO2 nanocomposites is a research hot top...The exceptional mechanical and electrical nature of grapheme makes it a viable candidate for enhancing the effectiveness of electrode material. In recent years, Graphene based SiO2 nanocomposites is a research hot topic of anode materials in lithium-ion batteries. In this paper, the amorphous SiO2 nanospheres/graphene composite was synthesized by hydrothermal method. Amorphous SiO2 is attached to the surface of graphene with a spherical structure and its average diameter is about 200 nm. The weight of SiO2 in the nanospheres composite is about 43%. Electrochemical tests showed that the amorphous SiO2 nanospheres/graphene composite exhibited the first charge and discharge capacity is respectively 329.5 mAhg-1 and 444.1 mAhg-1, and remain at 257.8 mAhg-1 and 274.6 mAhg-1 for 50th cycles at a current density of 200 mAg-1. The amorphous SiO2 nanospheres/graphene composite structure is novelty and the results are of great significance to the preparation and application of new anode materials.展开更多
To enhance the stress corrosion cracking(SCC)resistance,Zn was utilized as an alloy element to add in the AA5083 aluminum alloys.The effects of Zn content on the microstructures,mechanical properties and SCC resistanc...To enhance the stress corrosion cracking(SCC)resistance,Zn was utilized as an alloy element to add in the AA5083 aluminum alloys.The effects of Zn content on the microstructures,mechanical properties and SCC resistance were systematically evaluated.The results demonstrate that in the studied range adding Zn can significantly improve the SCC resistance of the AA5083 alloys.This is related to the relatively low amount of continuous β(Al3Mg2)phase along grain boundary and the formation of Zn-containing phase such as Al5Mg11Zn4 phase.Based on the results,the optimal Zn content with respect to SCC resistance is approximately 0.50 wt.%.Further increasing Zn content results in coarse precipitates discontinuously distributed along grain boundaries.展开更多
文摘The exceptional mechanical and electrical nature of grapheme makes it a viable candidate for enhancing the effectiveness of electrode material. In recent years, Graphene based SiO2 nanocomposites is a research hot topic of anode materials in lithium-ion batteries. In this paper, the amorphous SiO2 nanospheres/graphene composite was synthesized by hydrothermal method. Amorphous SiO2 is attached to the surface of graphene with a spherical structure and its average diameter is about 200 nm. The weight of SiO2 in the nanospheres composite is about 43%. Electrochemical tests showed that the amorphous SiO2 nanospheres/graphene composite exhibited the first charge and discharge capacity is respectively 329.5 mAhg-1 and 444.1 mAhg-1, and remain at 257.8 mAhg-1 and 274.6 mAhg-1 for 50th cycles at a current density of 200 mAg-1. The amorphous SiO2 nanospheres/graphene composite structure is novelty and the results are of great significance to the preparation and application of new anode materials.
基金financially supported by the Nature Science Research Project of Anhui Province(No.1808085QE136)the Anhui Postdoctoral Science Foundation(No.934269)the National Natural Science Foundation of China(No.51905143)。
文摘To enhance the stress corrosion cracking(SCC)resistance,Zn was utilized as an alloy element to add in the AA5083 aluminum alloys.The effects of Zn content on the microstructures,mechanical properties and SCC resistance were systematically evaluated.The results demonstrate that in the studied range adding Zn can significantly improve the SCC resistance of the AA5083 alloys.This is related to the relatively low amount of continuous β(Al3Mg2)phase along grain boundary and the formation of Zn-containing phase such as Al5Mg11Zn4 phase.Based on the results,the optimal Zn content with respect to SCC resistance is approximately 0.50 wt.%.Further increasing Zn content results in coarse precipitates discontinuously distributed along grain boundaries.
