Direct pyrolysis of melamine sponge toward nitrogen-doped carbon for high-performance lithium and sodium ion storage

Herein, we report a simple and green method to prepare nitrogen-doped carbon via direct pyrolysis of melamine sponge (MS). The as-prepared carbonized MS (CMS) can be employed as high-performance anode materials for both lithium ion batteries (LIBs) and sodium ion batteries (SIBs). After tailoring the nitrogen content and defect concentration of CMS samples by adjusting the pyrolysis temperature, the CMS synthesized at 700 °C delivers a high reversible capacity of 651 mA h g-1 after 400 cycles at 100 mA g−1 in LIBs. Even in SIBs, the CMS anode still displays a stable and long-term cyclability with a capacity of 161 mAh g−1 after 500 cycles at 100 mA g−1, demonstrating that the CMS is a promising anode material for both LIBs and SIBs.