Flower-like graphitic carbon derived from biomass for anode of potassium ion battery

The conventional graphite anode for potassium ion batteries (PIBs) can be structurally disrupted by intercalation of potassium ion with a large radius, resulting in the poor cycling stability and rate capability. Here an architecture of flower-like graphitic carbon (FLGC) derived from biomass is designed. As the anode for PIBs, FLGC achieves the stable performance and high-rate capability because of numerous mesopores, intrinsic defects, and a large interlayer spacing. FLGC presents a stable cycling performance (171 mAh g⁻¹ after 1700 cycles at 500 mA g⁻¹ with a capacity retention of 79.2 %) and a high potassium storage capacity (301 mAh g⁻¹ at 100 mA g⁻¹), in addition to low charge/discharge plateaus (0.35 V for charge and 0.12 V for discharge). More importantly, the mechanism for potassium storage and influence of intrinsic defects on the electrochemical performance are investigated. This study offers a novel design for graphitic structures, which is important for PIBs.