Chen He, Sun Ning, Wang YingXian, Soomro Razium Ali, Xu Bin
State Key Laboratory of Organic-Inorganic Composites, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, China.
Shaanxi Key Laboratory of Chemical Reaction Engineering, School of Chemistry and Chemical Engineering, Yan'an University, Yan'an, 716000, China.
Small. 2025 Feb;21(8):e2406497. doi: 10.1002/smll.202406497. Epub 2024 Sep 17.
Coal-based carbon material, characterized by abundant resources and low cost, has gained considerable interests as a promising anode candidate for sodium-ion batteries (SIBs). However, the coal-based carbon generally shows inferior Na-storage performance due to its highly-ordered microstructure with narrow interlayer spacing. Herein, a salt-assisted mechanical ball-milling strategy is proposed to disrupt the polycyclic aromatic hydrocarbon structure in anthracite molecules, thereby reducing the microcrystalline regularity of the derived carbon during following pyrolysis process. In addition, the induced C─O─C bonds during ball-milling process can alter the pyrolysis behavior of anthracite and restrain the formation of surface defects. Consequently, in contrast to pristine anthracite-based pyrolytic carbon, which exhibits a Na-storage capacity of 198.4 mAh g with a low initial Coulombic efficiency (ICE) of 65.1%, the ball-milling modified carbon assisted by NaCl salt (NAC), with enhanced structural disordering and reduced surface defects, demonstrate significantly improved Na-storage capacity of 332.1 mAh g and ICE value of 82.0%. The NAC electrode also realizes excellent cycle and rate performance, retaining a capacity of 196.0 mAh g at 1 C after 1000 cycles. Furthermore, when coupled with NaNiFeMnO cathode, the assembled Na-ion full cell deliveres an exceptional electrochemical performance, highlighting its promising prospect as high-performance anode for SIBs.
煤基碳材料以资源丰富、成本低为特点，作为一种有前景的钠离子电池（SIBs）负极候选材料受到了广泛关注。然而，煤基碳由于其具有高度有序的微观结构和狭窄的层间距，通常表现出较差的储钠性能。在此，提出了一种盐辅助机械球磨策略，以破坏无烟煤分子中的多环芳烃结构，从而在后续热解过程中降低衍生碳的微晶规整度。此外，球磨过程中诱导产生的C─O─C键可以改变无烟煤的热解行为并抑制表面缺陷的形成。因此，与原始无烟煤基热解碳相比，原始无烟煤基热解碳的储钠容量为198.4 mAh g，初始库仑效率（ICE）较低，为65.1%，而经NaCl盐（NAC）辅助球磨改性的碳，由于结构无序性增强和表面缺陷减少，表现出显著提高的储钠容量，为332.1 mAh g，ICE值为82.0%。NAC电极还实现了优异的循环和倍率性能，在1 C下循环1000次后容量保持在196.0 mAh g。此外，当与NaNiFeMnO正极耦合时，组装的钠离子全电池表现出优异的电化学性能，突出了其作为SIBs高性能负极的广阔前景。
