Zhang Miaomiao, Wei Hongyu, Zhou Yitong, Wen Weidong, Zhang Lin, Yu Xin-Yao
School of Materials Science and Engineering, Anhui University Hefei 230601 P. R. China
Institutes of Physical Science and Information Technology, Anhui University Hefei 230601 P. R. China
Chem Sci. 2024 Oct 1;15(43):18187-95. doi: 10.1039/d4sc04385e.
Parasitic side reactions and the formation of zinc dendrites in aqueous solutions severely hinder the practical application of Zn metal anodes. Carbon materials with high electrical conductivity and mechanical robustness are promising protective materials for Zn anodes. However, the zincophobic nature of carbon materials impedes the cycling stability of zinc-ion batteries. Herein, a versatile design strategy is proposed utilizing carbon doped with single atoms with atomically dispersed zincophilic sites as a multi-functional protective material for high-performance zinc anodes. Taking bismuth-single-atom-doped carbon (Bi SAs) as an example, density functional calculations verify that the introduction of bismuth single atoms can enhance zincophilicity, promote robust adhesion to zinc foil, and effectively suppress hydrogen evolution. Guided by theoretical calculations, Bi single-atom-doped carbon nanobelts are synthesized and employed as a protective material to stabilize zinc anodes. As expected, due to the atomic-level zincophilic Bi sites, hydrophobicity, and enhanced ionic conductivity, the Bi SAs@Zn anode demonstrates over 4200 h and 600 h of reversible cycling at 5 mA cm and 20 mA cm, respectively, in symmetric cells. Additionally, the Bi SAs@Zn//MnO full cell achieves a stable lifespan of 1000 cycles at 1 A g, retaining 95.58% of the initial capacity.
寄生副反应以及水溶液中锌枝晶的形成严重阻碍了锌金属负极的实际应用。具有高导电性和机械稳定性的碳材料是很有前景的锌负极保护材料。然而，碳材料的憎锌性阻碍了锌离子电池的循环稳定性。在此，提出了一种通用的设计策略，利用掺杂有单原子且具有原子分散亲锌位点的碳作为高性能锌负极的多功能保护材料。以铋单原子掺杂碳（Bi SAs）为例，密度泛函计算证实铋单原子的引入可以增强亲锌性，促进与锌箔的牢固粘附，并有效抑制析氢。在理论计算的指导下，合成了铋单原子掺杂碳纳米带并用作保护材料来稳定锌负极。正如预期的那样，由于原子级亲锌铋位点、疏水性和增强的离子导电性，Bi SAs@Zn负极在对称电池中分别在5 mA cm和20 mA cm下表现出超过4200 h和600 h的可逆循环。此外，Bi SAs@Zn//MnO全电池在1 A g下实现了1000次循环的稳定寿命，保留了初始容量的95.58%。
