Synthesis and characterization of Li2FeP2O7/C nanocomposites as cathode materials for Li-ion batteries

• Li2FeP2O7/C were prepared by a simple solid-state reaction.
• Carbon coating and reducing particle size are adopted to improve the discharge capacity.
• The detailed study about the electrochemical properties of Li2FeP2O7 is scarce.
• Li2FeP2O7/C show superior electrochemical properties.

The pristine Li2FeP2O7 and Li2FeP2O7/C nanocomposites with different content of carbon have been successfully synthesized via a simple solid-state reaction, using cheap glucose as carbon source. XRD and EDS patterns demonstrate the high purity of the products. SEM images exhibit that the size of the particles is about 50–500 nm. Electrochemical measurements reveal that carbon coating and reducing particle size significantly enhance the electrochemical performances of Li2FeP2O7. Particularly, the Li2FeP2O7/C sample with a carbon content of 4.88 wt.% displays the best performance with a specific discharge capacity of 103.1 mAh g−1 at 0.1 C, which is 93.7% of its one-electron theoretical capacity, meaning 110 mAh g−1. Meanwhile, it shows favorable cycling stability and excellent rate performance, indicating its potential applicability in Li-ion batteries in the long term.