Benefiting from the distinctive ordering degree and local microstructure characteristics, hard carbon (HC) is considered as the most promising anode for sodium-ion batteries (SIBs). Unfortunately, the low initial Coulombic efficiency (ICE) and limited reversible capacity severely impede its extensive application. Here, a homogeneous curly graphene (CG) layer with a micropore structure on HC is designed and executed by a simple chemical vapor deposition method (without catalysts). CG not only improves the electronic/ionic conductivity of the hard carbon but also effectively shields its surface defects, enhancing its ICE. In particular, due to the spontaneous curling structural characteristics of CG sheets (CGs), the micropores (≤ 2 nm) formed provide additional active sites, increasing its capacity. When used as a sodium-ion battery anode, the HC-CG composite anode displayed an outstanding reversible capacity of 358 mAh·g⁻¹, superior ICE of 88.6%, remarkable rate performance of 145.8 mAh·g⁻¹ at 5 A·g⁻¹, and long cycling life after 1000 cycles with 88.6% at 1 A·g⁻¹. This work provides a simple defect/microstructure turning strategy for hard carbon anodes and deepens the understanding of Na⁺ storage behavior in the plateau region, especially on the pore-filling mechanism by forming quasi-metallic clusters.

受益于独特的有序度和局部微观结构特征，硬碳（HC）被认为是钠离子电池（SIB）最有前途的负极。不幸的是，较低的初始库仑效率（ICE）和有限的可逆容量严重阻碍了其广泛应用。在这里，通过简单的化学气相沉积方法（无催化剂）设计并执行了在 HC 上具有微孔结构的均匀卷曲石墨烯 (CG) 层。CG不仅提高了硬碳的电子/离子导电性，而且有效地屏蔽了其表面缺陷，增强了其ICE。特别是，由于 CG 片 (CG) 的自发卷曲结构特征，形成的微孔 (≤ 2 nm) 提供了额外的活性位点，从而增加了其容量。用作钠离子电池负极时，⁻¹ ，优异的ICE为88.6%，在5 A·g ⁻¹下的倍率性能为145.8 mAh·g ⁻¹，1000次循环后的循环寿命为88.6% 在1 A·g ⁻¹下。这项工作为硬碳负极提供了一种简单的缺陷/微观结构转变策略，加深了对高原地区Na ⁺存储行为的理解，特别是通过形成准金属团簇的孔隙填充机制。