Hydrogen Bond Shielding Effect for High-Performance Aqueous Zinc Ion Batteries

Manganese oxides are highly desirable for the cathode of rechargeable aqueous zinc ion batteries (AZIBs) owing to their low cost and high abundance. However, the terrible structure stability of manganese oxide limits its practical application. Here, it is demonstrated that the hydrogen-bond shielding effect can improve the electrochemical performance of manganese oxide. Briefly, (NH₄ )_0.125 MnO₂ (NHMO) is prepared by introducing NH₄ ⁺ into the tunnel structure of α-MnO₂ . The robust hydrogen bonds between N-H and host O atoms can stabilize the lattice structure of α-MnO₂ and suppress the dissolution of Mn element. More importantly, it can also accelerate ions mobility kinetics by weakening the electrostatic interaction of host O atoms. Thus, the fabricated Zn||NHMO battery possesses impressive cycling life (99.5% of capacity retention over 10 000 cycles) and rate capability (109 mA h g^-1 of discharge capacity at 6000 mA g^-1 ). Comprehensive analyses reveal the essences of interfacial charge and bulk ions transfer. This finding opens new opportunities for the development of high-performance AZIBs.