Crystal Plane Reconstruction and Thin Protective Coatings Formation for Superior Stable Zn Anodes Cycling 1300 h.

Abstract

Some new insights into traditional metal pretreatment of anticorrosion for high stable Zn metal anodes are provided. A developed pretreatment methodology is employed to prefer the crystal plane of polycrystalline Zn and create 3.26µm protective coatings mainly consisting of organic polymers and zinc salts on Zn foils (ROZ@Zn). In this process, Zn metal exhibits a surface-preferred (001) crystal plane proved by electron backscattered diffraction. Preferred (001) crystal planes and ROZ coatings can regulate Zn2+ diffusion, promote flat growth of Zn, and prevent side reactions. As a result, ROZ@Zn symmetrical cells exhibit superior plating/stripping performance over 1300h. Impressively, it is significantly prolonged over 40times in comparison to the bare Zn symmetric cell at 5mAcm-2 . Moreover, Zn//MnO2 button cells have a high capacity retention of 96.3% after 1600cycles and pouch cells have a high capacity 122mAhg-1 after 200cycle at 5C. This work provides inspiration for high stable aqueous Zn metal batteries using the developed metal pretreatment of anticorrosion, which will be a viable, low-cost, and efficient technology. More interesting, it demonstrates the availability of reconstructing crystal planes by the largely heterogeneous reaction activation of the different crystal planes to H+ .