ZIF-8 modified the anode of the magnesium battery to improve the problems of voltage hysteresis and corrosion resistance

Abstract

Magnesium is a promising anode material. However, the magnesium anode will quickly react with the electrolyte to form an ion-insulated passivation film, resulting in voltage hysteresis. Because the magnesium anode is easily corroded, it leads to a decrease in its electrochemical performance. In this paper, the anode of the magnesium battery was modified by ZIF-8 coating. The ZIF-8 coating can largely prevent contact between water in the solution and the surface of the magnesium anode, which can inhibit the passivation of the magnesium anode. The voltage hysteresis time is significantly reduced from 4 s before modification to 0.3 s, which also effectively reduces the resistance of the battery. Compared with the unmodified magnesium battery, the modified magnesium battery has a larger initial voltage and a longer discharge platform. The anode utilization rate is doubled compared with that before modification, and the specific energy density is also greatly improved. The ZIF-8 coating with porous network structure and hydrophobicity can slow down the infiltration of corrosive substances to some degree, prolong its transmission path, and provide better protection for the magnesium anode.