Indexed on: 10 Sep '21Published on: 12 Dec '19Published in: Journal of Materials Science: Materials in Electronics
In order to improve the electrochemical performance of Si-based anode materials, a marvelous Si-based anode material was prepared with double-shell structure (Si/Ag@PM@MIL-100). The double-shell structure achieved a dual functions of the inner shell and the outer shell. The outer shell MIL-100 can promote the formation of a stable SEI film and enhance the synergistic effect of Si/Ag@PM. The three-dimensional interconnected porous carbon nanosheets and MWCNTs (PM) network of the inner shell can accommodated the volume expansion of Si during charge and discharge. It also effectively alleviated the press and prevented the pulverization of the Si particles. The structure also suppressed the aggregation of the nano-Ag particles. Nano-Ag and PM can improve the electrical conductivity of electrodes. The porous outer shell layer was obtained by HCl to dissolve iron oxide of the outer shell. The double-shell structure particles contained a large number of pores and interconnected channel. The structure is beneficial to the storage and rapid transportation of lithium ions. The high conductivity improved the conduction of electrons. The initial coulombic efficiency of the Si/Ag@PM@MIL-100 electrode reached 80.4% and maintained a specific discharge capacity of 615 mAh/g at a current density of 1 A/g with a capacity retention ratio of 62.9% after 500 cycles.