Low-temperature deposition of a zincophilic carbon layer for long-life zinc metal batteries

Aqueous zinc metal batteries (ZMBs) with environmental benign and low cost can be used for grid-scale energy storage, but have shortcomings of short cycling life mainly due to inferior reversibility of zinc metal anodes in mild aqueous electrolytes. Herein, a zincophilic carbon (ZC) layer is effectively deposited on Zn metal foil at low temperature of 450 °C via up-stream pyrolysis of a hydrogen-bonded supramolecular substances frameworks (HSFs), which is assembled by melamine (ME) and cyanuric acid (CA). Importantly, the zincophilic groups (e.g., C＝O and C＝N) in the ZC layer can guide uniform zinc plating/stripping and eliminate dendrites and side reactions. Therefore, the assembled symmetrical batteries (ZC@Zn//ZC@Zn) achieve a long-term serve time of 2500 h at 1 mA cm⁻² and 1 mAh cm⁻², obviously longer than that of bare Zn anodes (180 h). In addition, the assembled ZC@Zn//V₂O₅ full batteries exhibit a higher capacity of 174 mAh g⁻¹ after 1200 cycles at 2 A g⁻¹ than the Zn//V₂O₅ counterpart (100 mAh g⁻¹). The developed strategy for the low-temperature deposition of ZC layer paves a new way to construct advanced zinc metal anodes for advanced ZMBs.