Tian Yuan, An Yongling, Wei Chuanliang, Xi Baojuan, Xiong Shenglin, Feng Jinkui, Qian Yitai
SDU & Rice Joint Center for Carbon Nanomaterials, Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials (Ministry of Education), School of Materials Science and Engineering , Shandong University , Jinan , 250061 , P. R. China.
School of Chemistry and Chemical Engineering , Shandong University , Jinan , 250100 , P. R. China.
ACS Nano. 2019 Oct 22;13(10):11676-11685. doi: 10.1021/acsnano.9b05599. Epub 2019 Oct 8.
Dendrite growth of metal anodes is one of the key hindrances for both secondary aqueous metal batteries and nonaqueous metal batteries. In this work, a freestanding TiCT MXene@Zn paper is designed as both zinc metal anode and lithium metal anode host to address the issue. The binder-free TiCT MXene@Zn paper exhibits merits of good mechanical flexibility, high electronic conductivity, hydrophilicity, and lithiophilicity. The crystal growth mechanism of Zn metal on common Zn foil and TiCT MXene@Zn composite is also studied. It is found that the TiCT MXene@Zn paper can effectively suppress the dendrite growth of Zn, enabling reversible and fast Zn plating/stripping kinetics in an aqueous electrolyte. Moreover, the TiCT MXene@Zn paper can be used as a 3D host for a lithium metal anode. In this host, Zn is utilized as a nucleation agent to suppress the Li dendrite growth. The freestanding TiCT MXene@Zn@Li anode exhibits superior reversibility with high Coulombic efficiency (97.69% over 600 cycles at 1.0 mA cm) and low polarization compared with the Cu@Li anode. These findings may be useful for the design of dendrite-free metal-based energy storage systems.
金属阳极的枝晶生长是水系二次金属电池和非水系金属电池面临的关键阻碍之一。在这项工作中，一种独立的TiCT MXene@Zn纸被设计用作锌金属阳极和锂金属阳极主体，以解决这一问题。不含粘结剂的TiCT MXene@Zn纸具有良好的机械柔韧性、高电子导电性、亲水性和锂亲性等优点。还研究了普通锌箔和TiCT MXene@Zn复合材料上锌金属的晶体生长机制。研究发现，TiCT MXene@Zn纸可以有效抑制锌的枝晶生长，在水系电解质中实现可逆且快速的锌电镀/剥离动力学。此外，TiCT MXene@Zn纸可用作锂金属阳极的三维主体。在这个主体中，锌被用作成核剂来抑制锂枝晶生长。与Cu@Li阳极相比，独立的TiCT MXene@Zn@Li阳极表现出优异的可逆性，具有高库仑效率（在1.0 mA cm下600次循环中为97.69%）和低极化。这些发现可能有助于设计无枝晶的金属基储能系统。
