Controllable synthesis of cypress-derived hard carbon for high-rate sodium ion storage

Abstract

Optimized chemical pretreatment method facilitates the synthesis of biomass-based hard carbon with rich porosity at lower carbonization temps (900–1300 °C), yielding cost-effective and high-performance anode materials. The cypress-derived hard carbon (WC-1100) with hierarchical pores achieves a peak sodium ion storage of 307 mA h g⁻¹ at 0.1 A g⁻¹ with an impressive ICE of 82.5%.