One-pot synthesis of N-doped carbon nanosheets from Victorian brown coal with enhanced lithium storage

We report a novel one-pot synthesis method of N-doped porous carbon nanosheets (NCNS) from Victorian brown coal (VBC), which puts forward a sustainable alternative method of utilizing these vast and low-cost resources. VBC and urea were used as the carbon and nitrogen sources in the synthesis process. Benefiting from the porous nanosheet structure and doped N atoms in the carbon matrix, the prepared NCNS at a VBC:urea ratio of 1:3 delivered a promising specific capacity of 604.7 mAh/g at the current density of 50 mA/g. After the cycling performance under 1000 cycles at 1000 mA/g, the reversible capacity remained at 303.6 mAh/g (capacity retention of 97.43%), suggesting a superior stability. Various analytical techniques were used to establish the formation mechanism of NCNS in the presence of urea as well as the charge storage behavior and mechanism in the developed NCNS. The proposed process has great potential for the efficient conversion of VBC into highperformance carbon anode materials for LIBs.