Three‐dimensional electrically conductive–hydrophobic layer for stable Zn metal anodes

Abstract

Abstract The interrelated side reactions and dendrites growth severely destabilize the electrode/electrolyte interfaces, resulting in the difficult application of aqueous Zn ion batteries (AZIBs). Hydrophobic protective layer possesses natural inhibition ability for side reactions. However, the conventional protective layer with plane structure is difficult to attain joint regulation of side reaction and Zn nucleation. Herein, a novel three‐dimensional (3D) electrically conductive and hydrophobic (3DECH) interface is elaborated to enable stable Zn anode. The as‐prepared 3DECH interface presents a uniform 3D morphology with hydrophobic property, large specific surface area, abundant zincophilic sites, and excellent electroconductivity. Therefore, the 3DECH interface achieves uniform nucleation and dendrite‐free deposition from synergetic benefits: (1) increased nucleation sites and reduced local current density through the special 3D structure and (2) uniform electric potential distribution and rapid Zn2+ transport due to the electroconductive alloy chemistry, thus coupling the hydrophobic property to obtain a highly reversible Zn anode. Consequently, the modified anode achieves a superior coulombic efficiency of 99.88% over 3500 cycles, and the pouch cells using modified anode and LiMn2O4 (LMO) cathode retain a capacity of 84 mAh g−1 after 700 cycles at a reasonable depth discharge of 36%, without dendrite piercing and “dead Zn.”

Keywords

• electroconductive layer
• flat deposition
• hydrophobic layer
• three‐dimensional surface
• zinc‐metal anode