Kwon, Minhyung Jeon, Seungyun Hwang, Uichan Kwon, Eunji Shin, Hee-Kang Yu, Seungho Kim, Dong-Ik Hong, Jihyun Lee, Minah 2026-02-26T05:30:08Z 2026-02-26T05:30:08Z 2026-02-26 2026-03 2405-8297 https://pubs.kist.re.kr/handle/201004/154371 The practical implementation of aqueous Zn-ion batteries (AZIBs) is hindered by the irreversibility of Zn metal anodes, which suffer from heterogeneous electrodeposition coupled with parasitic hydrogen evolution reactions (HER). While substrate engineering is essential to address this issue, the HER activity of substrates and its modulation to achieve homogeneous Zn nucleation and growth have been largely overlooked. Here, we investigate the interplay between HER suppression and Zn deposition behavior by tailoring surface chemistry of Cu current collectors. Specifically, we introduce a deep eutectic solvent (DES) treatment that simultaneously removes native oxides and forms a choline-derived organic nanolayer on Cu surface as an alternative to conventional acid or thermal pretreatments. This unique interface not only inhibits proton reduction but also promotes conformal Cu–Zn alloy formation, thereby enhancing Zn binding and further suppressing HER. Such dynamic surface evolution collectively mitigates insulating byproducts formation and enables dense Zn growth with enlarged grains (>2 μm) and a thickness closely matching that of Zn foil (106 %). Consequently, Zn anodes deposited on DES-treated Cu deliver a cumulative capacity of 5.8 Ah cm-2 at 30 % depth of discharge (DOD) and retain 2.2 Ah cm-2 even at 50 % DOD, highlighting their potential for practical, high-performance AZIBs. English Elsevier BV Tailoring electrochemical interface to regulate competition between Zn deposition and hydrogen evolution in aqueous rechargeable batteries Article 10.1016/j.ensm.2026.104960 1 Energy Storage Materials, v.86 Energy Storage Materials 86 N scie scopus 001688604300002 2-s2.0-105029401373 Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Science & Technology - Other Topics Materials Science Article ZINC-ION BATTERIES COPPER XPS ELECTRODEPOSITION SURFACES GROWTH ALLOY VAPOR ANODE OXIDE Deep eutectic solvent Hydrogen evolution reaction Substrate engineering Aqueous Zn batteries Cu-Zn alloy