Ultrasmall Sn Nanoparticles Embedded in Nitrogen-Doped\nPorous Carbon As High-Performance Anode for Lithium-Ion Batteries

Abstract

In\nthis Letter, we reported on the preparation and Li-ion battery\nanode application of ultrasmall Sn nanoparticles (∼5 nm) embedded\nin nitrogen-doped porous carbon network (denoted as 5-Sn/C). Pyrolysis\nof Sn­(Salen) at 650 °C under Ar atmosphere was carried out to\nprepare N-doped porous 5-Sn/C with the BET specific surface area of\n286.3 m² g^–1. The 5-Sn/C showed an initial\ndischarge capacity of 1014 mAh g^–1 and a capacity\nretention of 722 mAh g^–1 after 200 cycles at the\ncurrent density of 0.2 A g^–1. Furthermore, a reversible\ncapacity of ∼480 mAh g^–1 was obtained at\nmuch higher current density of 5 A g^–1. The remarkable\nelectrochemical performance of 5-Sn/C was attributed to the effective\ncombination of ultrasmall Sn nanoparticles, uniform distribution,\nand porous carbon network structure, which simultaneously solved the\nmajor problems of pulverization, loss of electrical contact, and particle\naggregation facing Sn anode.