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Two Birds One Stone: Graphene Assisted Reaction Kinetics and Ionic Conductivity in Phthalocyanine-Based Covalent Organic Framework Anodes for Lithium-ion Batteries |
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| Authors: | Jianjun Zhao Miaomiao Zhou Jun Chen Luyi Wang Qian Zhang Shengwen Zhong Haijiao Xie Yutao Li |
| Affiliation: | 1. School of Materials Science and Engineering, Jiangxi Provincial Key Laboratory of Power Batteries and Materials, Jiangxi University of Sciences and Technology, Ganzhou, 341000 China
State Key Laboratory of Chemical Resources Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Chemistry, Beijing University of Chemical Technology, Beijing, 100029 China;2. School of Materials Science and Engineering, Jiangxi Provincial Key Laboratory of Power Batteries and Materials, Jiangxi University of Sciences and Technology, Ganzhou, 341000 China School of Chemical&Environmental Engineering, China University of Mining and Technology(Beijing), Beijing, 100083 China;3. School of Materials Science and Engineering, Jiangxi Provincial Key Laboratory of Power Batteries and Materials, Jiangxi University of Sciences and Technology, Ganzhou, 341000 China;4. Hangzhou Yanqu Information Technology Co., Ltd. Y2, 2nd Floor, Building 2, Xixi Legu Creative Pioneering Park, No. 712 Wen'er West Road, Xihu District, Hangzhou City, Zhejiang Province, 310003 P.R. China;5. Institute of Physics (IOP), Chinese Academy of Sciences, Beijing, 100190 China |
| Abstract: | This work reports a covalent organic framework composite structure (PMDA-NiPc-G), incorporating multiple-active carbonyls and graphene on the basis of the combination of phthalocyanine (NiPc(NH2)4) containing a large π-conjugated system and pyromellitic dianhydride (PMDA) as the anode of lithium-ion batteries. Meanwhile, graphene is used as a dispersion medium to reduce the accumulation of bulk covalent organic frameworks (COFs) to obtain COFs with small-volume and few-layers, shortening the ion migration path and improving the diffusion rate of lithium ions in the two dimensional (2D) grid layered structure. PMDA-NiPc-G showed a lithium-ion diffusion coefficient (DLi+) of 3.04 × 10−10 cm2 s−1 which is 3.6 times to that of its bulk form (0.84 × 10−10 cm2 s−1). Remarkably, this enables a large reversible capacity of 1290 mAh g−1 can be achieved after 300 cycles and almost no capacity fading in the next 300 cycles at 100 mA g−1. At a high areal capacity loading of ≈3 mAh cm−2, full batteries assembled with LiNi0.8Co0.1Mn0.1O2 (NCM-811) and LiFePO4 (LFP) cathodes showed 60.2% and 74.7% capacity retention at 1 C for 200 cycles. Astonishingly, the PMDA-NiPc-G/NCM-811 full battery exhibits ≈100% capacity retention after cycling at 0.2 C. Aided by the analysis of kinetic behavior of lithium storage and theoretical calculations, the capacity-enhancing mechanism and lithium storage mechanism of covalent organic frameworks are revealed. This work may lead to more research on designable, multifunctional COFs for electrochemical energy storage. |
| Keywords: | carbonyl covalent organic frameworks graphene lithium ion batteries organic electrodes phthalocyanine |