Nitrogen configuration dependent holey active sites toward enhanced K+ storage in graphite foam

JOURNAL OF POWER SOURCES

卷:419

Article

Wang, Huanhuan^1,2  Yang, Guang²  Chen, Zhen⁴  Liu, Jilei³  Fan, Xiaofeng^5,6  Liang, Pei⁷  Huang, Yizhong²  Lin, Jianyi⁴  Shen, Zexiang^1,2,4 

[1] CINTRA CNRS NTU Thales, UMI 3288,50 Nanyang Dr, Singapore 637553, Singapore

[2] Nanyang Technol Univ, Sch Mat Sci & Engn, 50 Nanyang Ave, Singapore 639798, Singapore

[3] Hunan Univ, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China

[4] Nanyang Technol Univ, Sch Phys & Math Sci, 21 Nanyang Link, Singapore 637371, Singapore

[5] Jilin Univ, Minist Educ, Key Lab Automobile Mat, Changchun 130012, Jilin, Peoples R China

[6] Jilin Univ, Coll Mat Sci & Engn, Changchun 130012, Jilin, Peoples R China

[7] China Jiliang Univ, Sch Coll Opt & Elect Technol, Hangzhou 310038, Zhejiang, Peoples R China

关键词: Potassium ion batteries;    Pyridinic/pyrrolic nitrogen;    Holey structures;    Capacity enhancement;   

DOI  :  10.1016/j.jpowsour.2019.02.029

来源: Elsevier

【 摘 要 】

The nitrogen doping generally plays an important role in alkali-ion storage. Herein the nitrogen doping effect on K+ storage in graphite foam is explored. Experimental and theoretical calculations reveal that the K+ storage behavior is strongly dependent on nitrogen doping concentration and doping configurations. Specifically, high doping level i) provides more pyridinic/pyrrolic nitrogen content, thus creating more holey structures for K+ storage, ii) enlarges interlayer spacing to facilitate K+ intercalation, and iii) increases electronic conductivity to ensure fast kinetics. For the first time, we proved that the holey structure, rather than nitrogen doping, contributes to the capacity enhancement for carbon-based potassium ion batteries. Our investigations promote better understanding of K+ ion storage mechanism in doped graphite and provide invaluable guidance to optimize carbon-based electrode design for high-performance potassium ion batteries.

【 授权许可】

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