An investigation of the structure and electrochemical performance of N-doped carbon anodes derived from poly (acrylonitrile-co-itaconic acid) /pyrolytic lignin/zinc borate

Pyrolytic lignin (PyL) and zinc borate (ZB) are added to poly (acrylonitrile-co-itaconic acid) (PANIA) to facilitate the fabrication and improve the electrochemical performance. The carbonised PANIA/PyL/ZB (CPPZ) anodes with in-situ self-doped nitrogen are fabricated, demonstrating a higher char yield, a higher fabrication efficiency, and optimal carbon structures. It finds that PANIA, PyL and ZB have synergic effects with each other on improving thermal stability, resulting in a 16.21% enhancement of residue at 700°C from the calculated value. During thermal stabilisation, PyL and ZB accelerate the formation of conjugated ladder structures at 230°C. After carbonisation under 700°C, CPPZ-700 has relatively higher contents of pyridinic N (34.62%) and pyrrolic N (50.43%), and a larger interlayer space (0.46 nm). As an anode of sodium-ion battery, CPPZ-700 illustrates a reversible specific capacity of 180 mAh g−1 at a current density of 100 mA g−1, which is 120 mAh g−1 higher than PANIA-based carbon anode under the same conditions.