软@硬复合炭结构设计及其协同电化学储钾  

Hard@soft composite carbon anodes towards synergistic potassium storage

作　　者：陈亚鑫 蔡雅菱 曹振江 甘明涛 郭楠楠 鞠治成[1] CHEN Yaxin;CAI Yaling;CAO Zhenjiang;GAN Mingtao;GUO Nannan;JU Zhicheng(School of Materials Science and Physics,China University of Mining and Technology,Xuzhou 221116,China;School of Materials Science and Engineering,Beihang University,Beijing 100191,China;State Key Laboratory of Chemistry and Utilization of Carbon-based Energy Resource,Xinjiang University,Urumqi 830046,China)

机构地区：[1]中国矿业大学材料与物理学院,徐州221116 [2]北京航空航天大学材料科学与工程学院,北京100191 [3]新疆大学省部共建碳基能源资源化学与利用国家重点实验室,乌鲁木齐830046

出　　处：《复合材料学报》2023年第1期192-200,共9页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(21975283);博士后科学基金(2020M681762);省部共建碳基能源资源化学与利用国家重点实验室开放课题(KFKT2021007);中国科学院炭材料重点实验室开放基金(KLCMKFJJ2010)。

摘　　要：软@硬复合炭结构有助于协同改善炭负极材料的电化学储钾性能,但目前对不同复合结构对电化学储钾性能的影响规律仍缺乏系统研究。有鉴于此,将罗丹宁和嵌段共聚物F127作为硬炭前驱体,煤沥青热挥发份作为软炭前驱体,通过共炭化与气相沉积的协同使用,开发硬炭、软/硬三维杂化炭结构、软炭壳@硬炭核复合结构,并研究3种结构对电化学储钾性能的影响。软炭壳@硬炭核复合材料具有高可逆容量(0.05 A·g^(-1)下容量为365 mA·h·g^(-1))、高循环稳定性(100圈循环后容量保持率为80%)、高倍率性能(1 A·g^(-1)下容量为177 mA·h·g^(-1))的特征。硬炭核丰富的缺陷活性位点可提高复合材料储钾容量。软炭壳的涡轮碳结构可覆盖硬炭表面缺陷,促进钾离子去溶剂化嵌入以改善循环稳定性。此外,高导电性软炭壳可改善电荷交换,进而提高复合材料的倍率性能并缓解电压滞后。得益于软炭与硬炭复合结构的协同储钾机制,软炭壳@硬炭核复合材料表现出明显优于硬炭的电化学储钾性能。Hard@soft composite carbon can improve the potassium storage performance synergistically by combining the advantage of hard carbon and soft carbon.But the potassium storage mechanism of different composite structure is lack.Here,rhodanine and F127 were used as the precursor of hard carbon,and the volatile matter of coal tar pitch was used as the precursor of soft carbon.Hard carbon,soft/hard hybrid carbon and soft carbon shell@hard carbon core composite were fabricated using co-carbonization and chemical vapor deposition.When used as the anode materials of potassium-ion battery,soft carbon shell@hard carbon core composite possesses high reversible capacity(365 mA·h·g^(-1) at 0.05 A·g^(-1)),high cyclic stability(80%after 100 cycles),and excellent rate performance(177 mA·h·g^(-1) at 1 A·g^(-1)).It can be ascribed to the abundance of active sites of hard carbon and the coating of soft carbon on the defect sites at the surface of hard carbon.Moreover,the soft carbon can improve the conductivity of the composite,which can enhance the rate performance of composite anode and release the voltage hysteresis.Benefiting from the synergistic potassium storage,soft carbon shell@hard carbon core composite anode shows much better performance than hard carbon anode.

关 键 词：复合材料 炭材料 硬炭 软炭 钾离子电池 负极材料 

分 类 号：TB332[一般工业技术—材料科学与工程]