Polyethylene Glycol-Protected\nZinc Microwall Arrays\nfor Stable Zinc Anodes

Aqueous zinc-ion batteries promise good commercial application\nprospects due to their environmental benignity and easy assembly under\natmospheric conditions, positioning them as a viable alternative to\nlithium-ion batteries. However, some inherent issues, such as chaotic\nzinc dendrite growth and inevitable side reactions, challenge the\ncommercialization progress. In this work, we imprint highly ordered\nzinc microwall arrays to regulate the electric field toward uniform\nZn deposition. Afterward, coating a polyethylene glycol protection\nlayer on the zinc microwalls aims to passivate the surface defects\nthat rise unintentionally by mechanical imprinting. Polyethylene glycol\ncan also boost oriented Zn deposition along the (002) plane and inhibit\nhydrogen gas production, further enhancing the stability of such three-dimensional\n(3D) hybrid anodes. Compared to the messy electric field near the\npolyethylene glycol-protected Zn foil, the uniform electric field\nprovided by these 3D hybrid anodes can regulate the Zn deposition\nbehaviors, enabling a longer lifespan and thus certifying the necessity\nof adding 3D microstructures. Additionally, 3D microstructures can\noffer a larger surface area than that of the planar Zn foil, providing\nmore reaction sites and higher specific capacity. In this case, the\n3D hybrid electrode exhibits a good initial capacity of approximately\n120 mA h/g at a current density of 5 A/g and a nice retention of more\nthan 80% after 800 cycles. The proposed scheme paves the way for a\nlong-term stable 3D zinc anode solution with promising application\nprospects.