Surface Decoration Manipulating Zn2+/H+ Carrier Ratios for Hyperstable Aqueous Zinc Ion Battery Cathode

Abstract Aqueous zinc ion batteries (AZIBs) show great prospects in large‐scale energy storage applications, whereas this technology suffers from the lack of cathode materials with high capacity and stability. Here, a cathode material of SbO 2 nanoparticles decorated onto the surface of K 0.43 V 6 O 13 nanobelt is presented. The SbO 2 is disclosed as proton‐phile and zinc‐phobic, which thus favors H + intercalation. In consequence, the increase of H + intercalation can offset the lattice shrinkage caused by Zn 2+ intercalation, and contribute to excellent cyclic stability of the battery. Finally, SbO 2 /K 0.43 V 6 O 13 delivers a reversible capacity of 414.2 mAh g −1 at 1 A g −1 after 1000 cycles with a retention of 103%, and 223.5 mAh g −1 at 20 A g −1 after 20 000 cycles with a retention of 89.3%, showing long cycling life at both low current and high current densities. This study provides new insights into the effecting factors for the performance of AZIBs cathode and an effective strategy to improve its stability.