钾离子电池(PIBs)在大规模能源储存方面展现出良好的应用前景，制备高性能负极材料对于钾离子电池的发展至关重要。得益于其结构的多样性，炭材料被认为是最有希望实现商业化应用的负极材料。然而，炭材料的结构及其电化学性能之间的构效关系仍不明确。本文通过在600～1400 ℃的范围内调节炭化温度，制备了一系列结构不同的沥青基炭材料，其中，MTP700样品具有较高无序度和较大碳层间距，表现出329。4 mAh g-1的高可逆容量和72。81％的首次库伦效率，且在5 C大电流倍率下，储钾容量仍能保持144。2 mAh g-1。本文系统分析了炭材料结构和储钾性能随炭化温度的变化规律，揭示了炭材料微晶尺寸与低电位平台区容量以及缺陷、无序程度与斜线区容量的对应关系，有助于加深对炭负极材料储钾过程的理解，推动钾离子电池的快速发展。
Synthesis of pitch-derived carbon anodes for high-performance potassium-ion batteries
Potassium-ion batteries(PIBs)hold promise for large-scale energy storage,necessitating the development of high-per-formance anode materials.Carbons with the advantage of structural versatility,are recognized as the most promising anode materials for their commercialization,however the relationship between the carbon anode structure and its electrochemical performance re-mains unclear.A series of pitch-based soft carbons with different structures were fabricated using carbonization temperatures in the range 600-1400 ℃,and their changes in carbon configuration and K-storage performance as a function of carbonization temperature were investigated.Correlations between the carbon crystal size and the low-potential plateau region capacity and between the degree of structural disorder of the carbons with their sloping region capacity were revealed.Among all samples,that obtained by carboniza-tion at 700 ℃ had a relatively high degree of disorder and a large interlayer spacing,and had a high reversible capacity of 329.4 mAh g-1 with a high initial coulombic efficiency of 72.81％,and maintained a high capacity of 144.2 mAh g-1 at the current rate of 5 C.These findings improve our fundamental understanding of the K-storage process in carbon anodes,and thus facilitate the advance of PIBs.
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