Hierarchical pores from microscale to macroscale boost ultrahigh lithium intercalation pseudocapacitance of biomass carbon

Despite graphite has been commercialized in the lithium ion batteries, further exploration of biomass-derived carbon-based anode materials with high specific capacity and rate performance is necessary owning to their natural abundance and low-cost production. Heteroatoms-doped, hierarchical porous, high disordered, and two-end-open carbon nanorods with interconnected networks were fabricated via a green, sustained route using crab shell as both the biological template and activation reagent and honey as biomass carbon precursor. The hierarchical porous structure with heteroatoms-doping leads to a high surface area of 502.5 m² g⁻¹, sufficient defects/active sites, and the convenient access of ions to the electrochemically active surface. This elaborated architecture provides a fast ion/electron transfer pathway, demonstrating high pseudocapacitive charge storage behavior. As a result, the hierarchical porous carbon nanorod electrode delivers outstanding rate performance (374.1 mAh g⁻¹ at 5.0 A g⁻¹) and remarkable cycling stability (623.3 mAh g⁻¹ at 1.0 A g⁻¹ after 500 cycles), which may have the great potential of HPCRs as a sustainable high-rate carbon anode material for LIBs.