德国德雷斯顿工业大学Xinliang Feng团队研制了一种水溶液锌离子储能装置用高倍率二维聚芳酰亚胺共价有机骨架阳极。该研究成果于2020年11月9日发表在《美国化学会志》。

可再充式水溶液锌离子储能装置是下一代储能技术中非常有前途的一种候选装置。然而，缺乏具有低电位窗口的高可逆Zn2+储存阳极材料仍然是人们关注的主要问题。

研究人员研制了一种具有高动力学Zn2+储存能力的二维聚芳酰亚胺共价有机骨架（PI-COF）阳极。PI-COF的孔道结构良好，具有很高的内建氧化还原活性羰基和低势垒的离子扩散。所构建的PI-COF阳极具有特定的容量（332 C g–1或92 mAh g–1，0.7 a g–1），高速率容量（7Ag–1时为79.8%），长循环寿命（4000次循环中为85%）。原位拉曼光谱研究和第一性原理计算阐明了酰亚胺羰基可逆形成带负电荷的烯醇酸盐的Zn2+两步储存机理。采用PI-COF阳极与MnO2阴极耦合的方法制备了无枝晶全锌离子装置，其具有优良的能量密度（23.9～66.5 Wh kg–1）和超级电容器级功率密度（133～4782 W kg–1）。

该研究验证了共价有机骨架作为Zn2+储能阳极的可行性，为构建可靠的水储能装置提供了良好的前景。

附：英文原文

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

Author: Minghao Yu, Naisa Chandrasekhar, Ramya Kormath Madam Raghupathy, Khoa Hoang Ly, Haozhe Zhang, Evgenia Dmitrieva, Chaolun Liang, Xihong Lu, Thomas D. Kühne, Hossein Mirhosseini, Inez M. Weidinger, Xinliang Feng

Issue&Volume: November 9, 2020

Abstract: Rechargeable aqueous Zn-ion energy storage devices are promising candidates for next-generation energy storage technologies. However, the lack of highly reversible Zn2+-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 Zn2+-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 Zn2+-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 MnO2 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 Zn2+-storage anodes and shows a promising prospect for constructing reliable aqueous energy storage devices.

DOI: 10.1021/jacs.0c07992

Source: https://pubs.acs.org/doi/10.1021/jacs.0c07992