Liu Jiayi, Shen Zhongrong, Lu Can-Zhong
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China.
University of Chinese Academy of Sciences, Beijing, 101408, China.
Small Methods. 2025 Jan;9(1):e2400719. doi: 10.1002/smtd.202400719. Epub 2024 Oct 2.
Due to the presence of HO within the solvated sheath of [Zn(HO)] as well as reactive free water in the electrolyte bulk phase, the extended cycling of aqueous zinc-ion batteries (AZIBs) is significantly affected by detrimental side reactions and the growth of Zn dendrites. This study significantly enhances the long-term cycling stability of AZIBs by introducing a small amount of disodium malate (DM) into a 2 m ZnSO electrolyte solution. DM involvement in the solvation sheath of Zn reduces the desolvation energy of Zn, thereby mitigating the corrosion and hydrogen evolution reaction (HER) of the negative electrode surface by [Zn(HO)] ions. Additionally, DM adsorption on the zinc surface retards the reduction kinetics of Zn at anode, promoting uniform distribution and predominant deposition on the flat (002) crystal plane, thus reducing dendrite formation. The assembled Zn||Zn symmetric cell exhibits stable cycling for over 500 h at 10 mA cm and 5 mAh cm. The Zn||VO full cells with DM additive exhibits an ultralong cycling lifespan without capacity loss.
由于在[Zn(HO)]的溶剂化鞘层中存在HO以及电解质本体相中具有反应活性的游离水，水系锌离子电池（AZIBs）的长循环受到有害副反应和锌枝晶生长的显著影响。本研究通过向2 m ZnSO电解质溶液中引入少量苹果酸钠（DM），显著提高了AZIBs的长期循环稳定性。DM参与Zn的溶剂化鞘层，降低了Zn的去溶剂化能，从而减轻了[Zn(HO)]离子对负极表面的腐蚀和析氢反应（HER）。此外，DM在锌表面的吸附阻碍了阳极处Zn的还原动力学，促进了在平坦（002）晶面上的均匀分布和优先沉积，从而减少枝晶形成。组装的Zn||Zn对称电池在10 mA cm和5 mAh cm下表现出超过500 h的稳定循环。具有DM添加剂的Zn||VO全电池表现出超长的循环寿命且无容量损失。
