Lanthanum nitrate as aqueous electrolyte additive for favourable zinc metal electrodeposition

• Published in: Nature communications Vol. 13; no. 1; p. 3252
• Main Authors: Zhao, Ruirui, Wang, Haifeng, Du, Haoran, Yang, Ying, Gao, Zhonghui, Qie, Long, Huang, Yunhui
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06.06.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 147/135; 639/301; 639/301/299; 639/301/299/891; 639/4077/4079/891; 639/638/440/94; Anodes; Aqueous electrolytes; Batteries; Battery cycles; Charge distribution; Discharge; Electric double layer; Electrochemistry; Electrode materials; Electrodeposition; Electrolytes; Energy storage; Humanities and Social Sciences; Lanthanum; Metals; Morphology; multidisciplinary; Nitrates; Pollutant deposition; Renewable energy; Science; Science (multidisciplinary); Storage batteries; Sustainability; Zinc; Zinc sulfate
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-30939-8

Aqueous zinc batteries are appealing devices for cost-effective and environmentally sustainable energy storage. However, the zinc metal deposition at the anode strongly influences the battery cycle life and performance. To circumvent this issue, here we propose the use of lanthanum nitrate (La(NO 3 ) 3 ) as supporting salt for aqueous zinc sulfate (ZnSO 4 ) electrolyte solutions. Via physicochemical and electrochemical characterizations, we demonstrate that this peculiar electrolyte formulation weakens the electric double layer repulsive force, thus, favouring dense metallic zinc deposits and regulating the charge distribution at the zinc metal|electrolyte interface. When tested in Zn||VS 2 full coin cell configuration (with cathode mass loading of 16 mg cm −2 ), the electrolyte solution containing the lanthanum ions enables almost 1000 cycles at 1 A g −1 (after 5 activation cycles at 0.05 A g −1 ) with a stable discharge capacity of about 90 mAh g −1 and an average cell discharge voltage of ∼0.54 V. Zinc metal is a promising anode material for aqueous secondary batteries. However, the unfavourable morphologies formed on the electrode surface during cycling limit its application. Here, the authors report the tailoring of the surface morphology using a lanthanum nitrate aqueous electrolyte additive.