Lee, Sechan Kang, Inyeong Kim, Jihyeon Kim, So Hee Kang, Kisuk Hong, Jihyun 2024-01-19T16:31:46Z 2024-01-19T16:31:46Z 2021-09-02 2020-10 0378-7753 https://pubs.kist.re.kr/handle/201004/118018 Zinc aqueous batteries have attracted great attention due to the earth abundance and the low redox potential of Zn metal. Utilizing Zn metal as an anode, however, causes low coulombic efficiency stemming from a dendritic Zn plating and formation of byproducts such as hydrogen gas, solid zinc hydroxide and salt-related compounds. One effective way of mitigating the issues is to modify the solvation structure of the electrolyte to increase the energy barrier of the water molecules for hydrolysis and electrolysis. Nevertheless, Zn aqueous batteries still indiscriminately utilize several types of electrolytes without elucidating the correlation between electrolyte composition and the electrochemistry of Zn metal. Here, we use operando optical microscopy to visualize the microstructural evolution of Zn metal, which strongly affects the electrochemical reversibility. In ZnSO4 electrolyte, large Zn platelets grow and form loose agglomerates vulnerable to unexpected delamination from the electrodes. In Zn(OTf)(2) electrolyte, Zn platelets nucleate more homogeneously and grow smaller, which forms denser agglomerates enabling more stable cycling. We further reveal that the formation of a stable solidelectrolyte interphase layer holds the key to the excellent performance of acetonitrile-hybrid water-in-salt electrolytes. Our results show the necessity of designing proper electrolytes to develop long-life Zn aqueous batteries. English ELSEVIER Real-time visualization of Zn metal plating/stripping in aqueous batteries with high areal capacities Article 10.1016/j.jpowsour.2020.228334 1 JOURNAL OF POWER SOURCES, v.472 JOURNAL OF POWER SOURCES 472 N scie scopus 000558890300006 2-s2.0-85088010815 Chemistry, Physical Electrochemistry Energy & Fuels Materials Science, Multidisciplinary Chemistry Electrochemistry Energy & Fuels Materials Science Article MANGANESE-DIOXIDE NANOPARTICLES LITHIUM-METAL ZINC ELECTROLYTES ELECTRODEPOSITION MECHANISM ANODES DISSOLUTION CORROSION GRAPHITE Zn aqueous batteries Operando optical microscopy Zn dendrites SEI layer formation