Stable Zinc Electrode/Separator Interface Enabled by Phthalocyanine‐Modified Separator for Advanced Zinc Metal Batteries

Abstract Aqueous zinc (Zn) metal batteries (ZMBs) have received extensive attention as potential energy storage systems due to their inherent safety and low cost. However, the practical applications of ZMBs have been hindered by parasitic side reactions and Zn dendrite formation, undermining the efficiency of Zn anodes. With continuous research on the interfacial chemistry in ZMBs, increasing research interest is begun to focus on achieving dendrite‐free Zn electrodeposition by constructing a stable separator/electrode interface. In this report, a phthalocyanine (Pc)‐modified glass fiber (Pc‐GF) separator is proposed to enhance the separator/electrode interfacial chemistry and improve the stability of Zn electrode. This functionalized Pc‐GF separator can coordinate with Zn during plating and construct an electrostatic field layer to balance the interfacial electric field and Zn ion flux, facilitating stable dendrite‐free Zn electrodeposition. Consequently, the Zn symmetric cell using a Pc‐GF separator can perform 700 h stable plating/stripping at 2.0 mA cm −2 /2.0 mAh cm −2 . Moreover, the Zn//I 2 full cell using a Pc‐GF separator exhibites a capacity retention of 89.0% after 500 cycles at 0.5 C and a stable operation at 5.0 C for 6000 cycles. This approach provides an effective strategy to achieve a stable Zn electrode/separator interface in aqueous ZMBs.