The commercialization of sodium-ion batteries (SIBs) as an effective alternative to lithium-ion batteries (LIBs) has garnered considerable attention. Among the various anodes for SIBs, hard carbon (HC) with expanded carbon layer spacing is the most promising candidate for commercialization. However, the intricate structure of HC can impact the initial coulombic efficiency (ICE) and cycling performance of the cell, potentially resulting in suboptimal capacity and rate capabilities. Here we find that the waste Camellia semiserrata shell (CSshell) can serve as a precursor for biomass-derived HC material, featuring unique edge-graphitized carbon layer structures formed through direct carbonization, distinct from conventional reported HC structures. Such an edge-graphitized HC material exhibits an exceptional initial reversible capacity of 320.06 mA h g⁻¹ at a current density of 50 mA g⁻¹ and a capacity retention of 93.7% after 1200 cycles at 500 mA g⁻¹. The identification of the edge-graphited HC material, obtained from the waste CSshell, suggests a promising contender for low-cost and eco-friendly anode materials for SIBs.

中文翻译：

---

一种用于先进钠离子电池的独特边缘石墨硬碳


钠离子电池 （SIB） 作为锂离子电池 （LIB） 的有效替代品的商业化引起了相当大的关注。在 SIB 的各种负极中，具有扩大碳层间距的硬碳 （HC） 是最有希望商业化的候选者。然而，HC 的复杂结构会影响电池的初始库仑效率 （ICE） 和循环性能，可能导致容量和速率能力欠佳。在这里，我们发现废弃的 Camellia semiserrata 壳可以作为生物质衍生 HC 材料的前体，具有通过直接碳化形成的独特边缘石墨化碳层结构，区别于传统报道的 HC 结构。这种边缘石墨化 HC 材料在 50 mA g-1 的电流密度下表现出 320.06 mAh g-1 的出色初始可逆容量，在 500 mA g-1 下循环 1200 次后，容量保持率为 93.7%。从废弃的 Camellia semiserrata 壳中获得的边缘石墨化 HC 材料的鉴定表明，它是用于 SIB 的低成本和环保负极材料的有前途的竞争者。