A one-pot approach towards FeF_2-carbon core-shell composite and its application in lithium ion batteries

摘要

Core-shell nanorod with FeF_2 as core and graphitized carbon as shell was prepared by a one-pot thermal reaction using a mixture of ferrocene and polyvinylidene fluoride as precursor. The core-shell composite had an average length of about 1 μm and diameter ranging from 100 nm to 1 μm. The shell thickness was about 10-20 nm. Its electrochemical properties were studied in the potential range between 1.3 and 4.2 V at a current density of 30 mA g~(-1) at room temperature. The core-shell composite exhibited an initial discharge capacity of 345 mA h g~(-1). A reversible capacity of 217 mA h g~(-1) was maintained over 50 cycles with coulombic efficiency of 96% per cycle.