Yu Huaming, Chen Yuejiao, Wei Weifeng, Ji Xiaobo, Chen Libao
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, PR China.
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China.
ACS Nano. 2022 Jun 28;16(6):9736-9747. doi: 10.1021/acsnano.2c03398. Epub 2022 May 31.
Aqueous Zn metal batteries suffer from rapid cycling deterioration due to the severe water corrosion and dendrite growth on Zn anodes. Herein, a highly antiwater Zn-diethylenetriaminepenta(methylene-phosphonic acid) interface layer with good zinc affinity and special nanoscaled 3D granular structure is designed on Zn metal to address these problems. Experimental results combined with theoretical analysis and COMSOL simulations reveal that the hydrophobic groups in such Zn-based organic complex are the decisive factor in preventing HO from damaging Zn anode surface. The massive Zn attractive sites formed by interaction of methylene-phosphonic acid groups and Zn cause ion channel for fast zinc-ion adsorption and migration. And the developed nano granular architecture on the surface induces redistributed Zn ion flux to realize homogenization with smooth and compact surface deposition. Under the synergism, such modified anodes exhibit long cycling lifespan over 1300 h with a relatively low polarization voltage at 5 mA cm. Also, the assembled full cells (including Zn//VO and Zn//MnO cell) based on this anode are also demonstrated. The work provides a simple, low cost, and efficient pathway by combining the two concepts of structural design and constructing protective layers on the surface to prepare high-performance Zn anodes toward prospering aqueous zinc-metal batteries.
水系锌金属电池由于锌阳极上严重的水腐蚀和枝晶生长而遭受快速循环劣化。在此，在锌金属上设计了一种具有良好锌亲和力和特殊纳米级三维颗粒结构的高度抗水的锌-二乙烯三胺五（亚甲基膦酸）界面层来解决这些问题。实验结果结合理论分析和COMSOL模拟表明，这种锌基有机络合物中的疏水基团是防止羟基破坏锌阳极表面的决定性因素。亚甲基膦酸基团与锌相互作用形成的大量锌吸引位点为快速的锌离子吸附和迁移提供了离子通道。并且表面形成的纳米颗粒结构促使锌离子通量重新分布，以实现表面沉积均匀、平滑且致密。在这种协同作用下，这种改性阳极在5 mA cm下表现出超过1300 h的长循环寿命以及相对较低的极化电压。此外，还展示了基于该阳极组装的全电池（包括Zn//VO和Zn//MnO电池）。这项工作通过结合结构设计和在表面构建保护层这两个概念，为制备高性能锌阳极以推动水系锌金属电池发展提供了一条简单、低成本且高效的途径。
