Magnesium citrate induced growth of noodle-like porous graphitic carbons from coal tar pitch for high-performance lithium-ion batteries

Porous graphitic carbons are amongst the most attracted anode materials for lithium-ion batteries (LIBs) mainly because of their well-developed porous structure combined with desirable electrical conductivity. In this work, a novel induced growth strategy is introduced to synthesize noodle-like porous graphitic carbons (NPGCs) from low-cost coal tar pitch (CTP) using magnesium citrate as inducer and template. The as-prepared NPGCs have unique noodle-like carbon architecture consisting of cross-linked carbon chains with large specific surface area (~888.1 m2 g−1), high pore volume (~2.112 cm3 g−1) as well as desirable conductivity, and possess hierarchically porous structure containing favorable distribution of micro-, meso- and macropore and appropriate level of oxygen and nitrogen heteroatom doping. Due to these synergistic microstructure characteristics, the LIB anodes based on NPGCs exhibit remarkably improved electrochemical performance with an average reversible capacity (1157 mAh g−1 at 0.05 A g−1), superior rate capability (510 mAh g−1 at 2.0 A g−1) and an outstanding long-term cycling performance (95.3% capacity retention after 200 charge-discharge cycles). This work provides a novel strategy for cost-effective fabrication of more exciting microstructures of NPGCs with adjustable hierarchical porous structure and favorable conductivity from cheap carbon sources for anode materials in high-performance LIBs.