| Lithium-ion battery cathode material specific capacity is low,the new cathode material exploration and research for lithium secondary battery development is critical.Lithium-selenium batteries have a very attractive prospect.but there are still several technological challenges,such as shuttle effect that cause the low utilization of selenium,rapid loss of capacity,and low Coulombic efficiency;the drastic volume and low lithium ion and electron transport property during cycling.In this paper,we prepared two kinds of porous carbon materials and Se/C composite materials prepared by melt-diffusion method.The physical performances of all materials were characterized by XRD,BET,Raman,TEM,SEM and so on.The electrochemical performances were characterized by Galvanostatic cycling tests and Cyclic voltammetry?CV?tests.The N,P co-doped nanoporous carbon material was prepared by using glucose as carbon source,then encapsulated Se obtained composites Se/NPC as the cathode materials for Li-Se batteries.Se/NPC composites exhibit superior cycling stability and rate capability,the capacity retention of 420.6mAhg-1 after 100 cycles at 0.1C,the coulombic efficiency of approaching 99%,Se/NPC also shows excellent rate capability,the capacity remained at 443 mAhg-1 at 2C;when the current back to 0.1C,it recovered to 557 mAhg-1.Animal bone derived nanoporous carbon used as matrix for Li-Se battery,Nanoporous carbon was prepared by potassium hydroxide?KOH?activation with the pre-carbonized bone particles and impurities removed by washing with dilute nitric acid and deionized water.ABPC/Se composites was prepared by the melt-diffusion method.Li–Se batteries based on ABPC/Se composites cathode show excellent electrochemical performance with a high reversible capacity of 594 mAhg-1 after 97 cycles at 0.1C,the reversible specific capacity can reach 429 mAhg-1 at 2C.When the current density was tuned back to 0.1C,the reversible capacity can be recovered to 620 mAhg-1. |
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