A New Scalable Preparation of Metal Nanosheets: Potential Applications for Aqueous Zn-Ion Batteries Anode
A New Scalable Preparation of Metal Nanosheets: Potential Applications for Aqueous Zn-Ion Batteries Anode
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DOI：
10.1002/adfm.202003187
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发表时间：
2020-07-01
影响因子：
19
通讯作者：
Yan, Qingyu
中科院分区：
文献类型：
--
作者：
Wu, Chen;Tan, Huiteng;Yan, Qingyu
2D金属纳米片由于其维度相关的有趣特性而对各种应用具有吸引力;然而，其有效和可扩展的制备仍然是一个巨大的挑战。在此，相对活性的金属纳米片（例如，Zn，Al和Cu）的厚度下降到几个纳米，在低成本下，这涉及到一个初始的自折叠滚动步骤，然后由随后的超声波处理剥离它们没有任何蚀刻步骤。金属表面上的天然氧化物作为相邻金属层之间的屏障，在成功制备2D金属纳米片方面发挥着特殊作用。作为其实用性的证明，分层锌阳极，这是由锌微片与碳（锌MS@C）通过原位碳化羧甲基纤维素（CMC）粘合剂，成功地实现作为可充电水溶液锌离子电池的阳极。当应用于对称电池时，Zn MS@C在0.2 mA cm（-2）下提供超过800小时的长寿命，容量为0.1 mA h cm（-2）。重要的是，全电池的二氧化锰||Zn MS@C在300 mA g（-1）下循环140次后也表现出217.4 mA h g（-1）的高放电容量。
2D metal nanosheets are attractive for various applications stemming from the intriguing characteristics related with their dimensionality; however, their effective and scalable preparation remains a great challenge. Herein, a scalable preparation process of relatively active metal nanosheets (e.g., Zn, Al, and Cu) with the thickness down to several nanometers at low cost is demonstrated, which involves an initial self-folding-rolling step followed by the subsequent ultrasonication to exfoliate them without any etching step. The native oxide on the surface of the metals, which acts as a barrier between the adjacent metal layers, plays a special role in enabling the successful preparation of 2D metal nanosheets. As a demonstration for their practicability, a hierarchical Zn anode, which is constructed by the Zn microsheets coated with carbon (Zn MS@C) via in situ carbonization of carboxymethylcellulose (CMC) binder, is successfully implemented as anode for rechargeable aqueous Zn-ion batteries. When applied in symmetrical battery, the Zn MS@C delivers a long lifespan of over 800 h at 0.2 mA cm(-2)with a capacity of 0.1 mA h cm(-2). Importantly, the full battery of MnO2 || Zn MS@C also performs a high discharge capacity of 217.4 mA h g(-1)after 140 cycles at 300 mA g(-1).