1成果简介 锌金属阳极在水系锌离子电池(AZIBs)中的实际应用仍面临锌枝晶生长、氢进化反应(HER)及界面副反应等关键问题。为解决这些问题,本文,华南理工大学徐建铁 教授团队在《Small》期刊发表名为“UIO-66/Holey Graphene as a Surface Protective Layer for the Stabilization of Zn-Metal Anode for High Performance Aqueous Zinc Ion Batteries”的论文,研究通过原位生长UIO-66纳米晶体于来自废旧锂离子电池石墨的孔状石墨烯支架上,合理设计并合成了具有分级结构的UIO-66/孔状石墨烯(UIO-66/rhG0.1)复合材料,作为人工保护层。 UIO-66/rhG0.1复合材料通过UIO-66与多孔限制结构的协同作用,以及hG与多孔结构的结合,实现了离子流均匀化和电场重新分布的双重调控。因此,优化后的对称电池在2700小时循环中展现出卓越的循环稳定性,电压滞后仅为44 mV,有效抑制了锌枝晶的形成和HER。当Zn@UIO-66/rhG0.1与NaV3O8正极搭配时,全电池在500次循环后仍保持62.4%的初始容量(220.8 mAh g−1),优于纯Zn阳极(59.4%和114.5 mAh g−1)。 2图文导读

图1、a) Schematic illustration of the synthesis route of UIO-66/rhG0.1 and comparison of Zn plating on Zn@UIO-66/rhG0.1 and bare Zn electrodes. SEM images of b) hG and c) UIO-66/rhG0.1. d) TEM image of UIO-66/rhG0.1. e) Cross-sectional SEM image of Zn@UIO-66/rhG0.1. f) Contact angles of Zn@UIO-66/rG0.1 and Zn@UIO-66/rhG0.1. g) XRD patterns of bare Zn and Zn@UIO-66/rhG0.1.

图2、a) EIS of bare Zn||Zn, Zn@UIO-66/rG0.1||Zn@UIO-66/rG0.1 and Zn@UIO-66/rhG0.1||Zn@UIO-66/rhG0.1 symmetric cells before cycling. b) CV curves and c) LSV curves of bare Zn||Cu, Zn@UIO-66/rG0.1||Cu, and Zn@UIO-66/rhG0.1||Cu asymmetric cells. d) Tafel curves of bare Zn, Zn@UIO-66/rG0.1, and Zn@UIO-66/rhG0.1 electrodes. e) XRD patterns of bare Zn, Zn@UIO-66/rG0.1, and Zn@UIO-66/rhG0.1 electrodes after 100 cycles. f) CA curves of Zn nucleation on bare Zn, Zn@UIO-66/rG0.1, and Zn@UIO-66/rhG0.1 electrodes. SEM images of Zn metal deposited on g) bare Zn and h) Zn@UIO-66/rhG0.1 electrodes with different plating times: 1, 5, 10, and 20 h.

图3、a) CE of Zn||Cu, Zn@UIO-66/rG0.1||Cu and Zn@UIO-66/rhG0.1||Cu asymmetric cells at a current density and plating capacity of 2 mA cm−2/1 mAh cm−2. b) Rate performance and c,d) long-term cycling performance at various current densities and plating capacities of Zn||Zn, Zn@UIO-66/rG0.1||Zn@UIO-66/rG0.1 and Zn@UIO-66/rhG0.1||Zn@UIO-66/rhG0.1 symmetric cells: (c) 1 mA cm−2/1 mAh cm−2 and (d) 10 mA cm−2/5 mAh cm−2. SEM images of e,h) Zn, f, i) Zn@UIO-66/rG0.1 and g, j) Zn@UIO-66/rhG0.1 after 100 cycles at 1 mA cm−2/1 mAh cm−2.

图4、a) CV curves, b) charge–discharge curves, c) rate performance, d) EIS before cycling, and (e) long-term cycling performance of Zn||NVO, Zn@UIO-66/rG0.1||NVO, and Zn@UIO-66/rhG0.1||NVO cells. Inset of Figure 4d is the equivalent circuit model. 3小结 综上所述,本研究报道了一种具有分级结构的UIO-66/多孔石墨烯(UIO-66/rhG)复合材料,作为先进界面保护层以稳定AZIBs中的锌金属阳极。通过将UIO-66纳米晶体的多孔限制效应与来自废旧锂离子电池石墨的孔状石墨烯的分层结构和3D质量传输通道相结合,UIO-66/rhG0.1实现了离子流均匀化和电场重新分布的双重调控。这种协同机制有效抑制了锌树枝状晶体的生长,减轻了界面副反应,并最小化了氢气释放(HER),从而实现了卓越的电化学稳定性。优化后的Zn@UIO-66/rhG0.1对称电池展现出超过2700小时的超长循环耐久性,且电压滞后仅为44 mV。而与NVO正极搭配的全电池配置相比同类方案(纯Zn阳极和Zn@UIO-66/rG0.1),其容量保持率和倍率性能均更优。增强的性能凸显了多孔结构在调控Zn²⁺沉积动力学和界面动力学中的关键作用。这项工作不仅为废旧锂离子电池材料的可持续利用提供了策略,还为未来设计高性能金属基负极的通用保护层范式奠定了基础。 文献:

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