A High-Rate Two-Dimensional Polyarylimide Covalent Organic Framework Anode for Aqueous Zn-Ion Energy Storage Devices

作者：Minghao Yu, Naisa Chandrasekhar, Ramya Kormath Madam Raghupathy, Khoa H. Ly, Haozhe Zhang, Evgenia Dmitrieva, Chaolun Liang, Xihong Lu, Thomas D. Kühne, Hossein Mirhosseini, Inez M. Weidinger, Xinliang Feng · 发表于：Journal of the American Chemical Society · 年份：2020 · DOI：10.1021/jacs.0c07992 · 被引用次数：403 · 研究领域：Advanced battery technologies research、Supercapacitor Materials and Fabrication、Advanced Battery Materials and Technologies

Rechargeable aqueous Zn-ion energy storage devices are promising candidates for next-generation energy storage technologies. However, the lack of highly reversible Zn 2+ -storage anode materials with low potential windows remains a primary concern. Here, we report a two-dimensional polyarylimide covalent organic framework (PI-COF) anode with high-kinetics Zn 2+ -storage capability. The well-organized pore channels of PI-COF allow the high accessibility of the build-in redox-active carbonyl groups and efficient ion diffusion with a low energy barrier. The constructed PI-COF anode exhibits a specific capacity (332 C g –1 or 92 mAh g –1 at 0.7 A g –1 ), a high rate capability (79.8% at 7 A g –1 ), and a long cycle life (85% over 4000 cycles). In situ Raman investigation and first-principle calculations clarify the two-step Zn 2+ -storage mechanism, in which imide carbonyl groups reversibly form negatively charged enolates. Dendrite-free full Zn-ion devices are fabricated by coupling PI-COF anodes with MnO 2 cathodes, delivering excellent energy densities (23.9 ∼ 66.5 Wh kg –1 ) and supercapacitor-level power densities (133 ∼ 4782 W kg –1 ). This study demonstrates the feasibility of covalent organic framework as Zn 2+ -storage anodes and shows a promising prospect for constructing reliable aqueous energy storage devices.