Liu Yu, Li Yuanxia, Huang Xiaomin, Cao Heng, Zheng Qiaoji, Huo Yu, Zhao Jingxin, Lin Dunmin, Xu Bingang
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, P. R. China.
Nanotechnology Center, Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077, P. R. China.
Small. 2022 Sep;18(38):e2203061. doi: 10.1002/smll.202203061. Epub 2022 Aug 19.
Zinc (Zn) metal possesses broad prospects as an anode for aqueous zinc-ion batteries (AZIBs) due to its considerable theoretical capacity of 820 mAh g . However, the Zn anode suffers from dendrite growth and side reactions during Zn stripping/plating. Herein, a Prussian blue analog of copper hexacyanoferrate (CuHCF) with a 3D open structure and rich polar groups (CN) is coated on Zn foil as a solid-state electrolyte (SSE) protection layer to protect the Zn anode. The CuHCF protection layer possesses low activation energy of 26.49 kJ mol , the high ionic conductivity of 7.6 mS cm , and a large Zn transference number of 0.74. Hence, the Zn@CuHCF||Zn@CuHCF symmetric cell delivers high cycling stability over 1800 h at 5 mA cm , an excellent depth of discharge of 51.3%, and the accumulative discharge capacity over 3000 mAh cm . In addition, the Zn//Ti@CuHCF asymmetric cell achieves the coulombic efficiency (CE) of 99.87% after 2000 cycles. More importantly, the Zn@CuHCF//V O full cell presents outstanding capacity retention of 87.6% at 10 A g after 3000 cycles. This work develops a type of material to form an artificial protection layer for high-performance AZIBs.
锌（Zn）金属作为水系锌离子电池（AZIBs）的负极具有广阔的前景，因为其理论容量高达820 mAh g 。然而，锌负极在锌剥离/电镀过程中会出现枝晶生长和副反应。在此，一种具有三维开放结构和丰富极性基团（CN）的普鲁士蓝类似物六氰合铁酸铜（CuHCF）被涂覆在锌箔上作为固态电解质（SSE）保护层，以保护锌负极。CuHCF保护层具有26.49 kJ mol的低活化能、7.6 mS cm的高离子电导率和0.74的大锌迁移数。因此，Zn@CuHCF||Zn@CuHCF对称电池在5 mA cm下可实现超过1800 h的高循环稳定性、51.3%的优异放电深度以及超过3000 mAh cm的累积放电容量。此外，Zn//Ti@CuHCF非对称电池在2000次循环后库仑效率（CE）达到99.87%。更重要的是，Zn@CuHCF//V O全电池在3000次循环后，在10 A g下具有87.6%的出色容量保持率。这项工作开发了一种材料，用于为高性能AZIBs形成人工保护层。
