Catalytic graphitization of porous graphitic carbon derived from needle coke as anode materials for lithium-ion batteries

Abstract In this work, potassium perferite (K 2 FeO 4 ) is used as a catalyst in a straightforward and effective process of simultaneous activation and graphitization to create porous graphitized carbon (PGC), with coal-based green needle coke acting as starting material. The impacts of heating temperatures and K 2 FeO 4 solution concentrations on the microstructure, morphology, and electrochemical lithium storage ability were thoroughly investigated. The as-synthesised PGC materials have a high specific surface area of 260.55 m 2 g −1 and a good three-dimensional porous structure. Optimized PGC material synthesized at a temperature of 900 °C and concentrations of K 2 FeO 4 solutions show excellent rate performance and cycling stability, making it a promising anode material for lithium-ion batteries (LIBs). At a current density of 100 mAg −1 , it has a comparatively high specific discharge capacity of 386.05 mAh g −1 together with strong cycling stability (90.79% retention rate after 400 cycles). It maintains a discharge capacity of 325 mAh g −1 in the multiplicity test at a high current density of 1600 mA g −1 . It takes less time, energy, and is much more efficient to complete the synchronous carbonization and graphitization of needle coke when potassium perferite is used as a catalyst, as opposed to traditional high-temperature graphitized technology and conventional two-step activation and graphitization strategy. The green needle coke-derived PGC materials include many active sites and defects, a high electrical conductivity, a shortened ion diffusion pathway, and a unique micro-mesoporous structure that makes them suitable electrode materials for lithium-ion batteries.