Synergistic “Anchor-Capture” Enabled by Amino and Carboxyl for Constructing Robust Interface of Zn Anode

• Published in: Nano-micro letters 2023-12, Vol.15 (1), p.205-205, Article 205
• Main Authors: Luo, Zhen, Xia, Yufan, Chen, Shuang, Wu, Xingxing, Zeng, Ran, Zhang, Xuan, Pan, Hongge, Yan, Mi, Shi, Tingting, Tao, Kai, Xu, Ben Bin, Jiang, Yinzhu
• Format: Article
• Language: English
• Subjects: Amino acids; Carboxyl group; Dendrite growth; Discharge; Electrolytes; Electrolytic cells; Engineering; Glycine; Interface stability; Manganese dioxide; Metal foils; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Polar groups; Rechargeable batteries; Robustness; Side reactions; Synergistic “anchor-capture” effect; Zn anode–electrolyte interface
• ISSN: 2311-6706; 2150-5551
• DOI: 10.1007/s40820-023-01171-w

Highlights The synergistic “anchor-capture” mechanism of polar groups on Zn stripping/plating process is firstly proposed. The amino group firmly anchors on Zn surface and the carboxyl group strongly captures Zn 2+ , constructing a robust anode–electrolyte interface and inducing uniform Zn deposition. The ultra-stable cycle lifespan of Zn–Zn symmetric cell (over 2800 h) and high utilization rate of Zn anode (the depth of discharge up to 68% for 200 h) are achieved under the proposal of synergistic “anchor-capture.” While the rechargeable aqueous zinc-ion batteries (AZIBs) have been recognized as one of the most viable batteries for scale-up application, the instability on Zn anode–electrolyte interface bottleneck the further development dramatically. Herein, we utilize the amino acid glycine (Gly) as an electrolyte additive to stabilize the Zn anode–electrolyte interface. The unique interfacial chemistry is facilitated by the synergistic “anchor-capture” effect of polar groups in Gly molecule, manifested by simultaneously coupling the amino to anchor on the surface of Zn anode and the carboxyl to capture Zn 2+ in the local region. As such, this robust anode–electrolyte interface inhibits the disordered migration of Zn 2+ , and effectively suppresses both side reactions and dendrite growth. The reversibility of Zn anode achieves a significant improvement with an average Coulombic efficiency of 99.22% at 1 mA cm −2 and 0.5 mAh cm −2 over 500 cycles. Even at a high Zn utilization rate (depth of discharge, DOD Zn ) of 68%, a steady cycle life up to 200 h is obtained for ultrathin Zn foils (20 μm). The superior rate capability and long-term cycle stability of Zn–MnO 2 full cells further prove the effectiveness of Gly in stabilizing Zn anode. This work sheds light on additive designing from the specific roles of polar groups for AZIBs.