Vascular tissue-derived hard carbon with ultra-high rate capability for sodium-ion storage

Vascular tissue helps quickly pass the nutrients and water through the plant. Inspiringly, the transport of electrolyte solutions within such biological tissue may also play an essential role in governing the high-current performance of sodium-ion storage. Herein, we report a facile and efficient approach to fabricate a vascular tissue-derived hard carbon (VHC) by an integrated procedure of leave stripping, carbonization and alkali/acid washing. By meticulously adjusting the pyrolysis temperatures, hierarchical microchannel carbon with abundant turbostratic nanodomains, suitable pore size and special surface functional groups can be obtained, enabling high specific capacity and excellent rate performances. It is believed that the vascular tissue-derived carbon can significantly shorten sodium ion transport paths and further enhance the storage performance on the surface and within the electrode materials, making it a promising candidate for sodium-ion batteries.