MXene ink hosting zinc anode for high performance aqueous zinc metal batteries

Abstract

Despite the safety, low cost, and high theoretical capacity (820 mA h g−1) of Zn metal anodes, the practical application of aqueous Zn metal batteries remains a critical challenge due to the Zn dendrite growth, corrosion, and hydrogen evolution reaction. Herein, we demonstrate the MXene ink hosting Zn metal anodes (MX@Zn) for high-performance and patternable Zn metal full batteries. The as-designed MX@Zn electrode is more facile and reversible than bare Zn and CC@Zn, as verified by better cyclic stability and lower overpotentials of symmetric cells with the plating capacity of 0.05 mA h cm−2 at 0.1 mA cm−2 and of 1 mA h cm−2 at 1 mA cm−2. The MX@Zn | MnO2 full cells deliver a high specific capacity of 281.9 mA h g−1, 91.5% of the theoretical capacity, achieving 50% capacity retention from 60 mA g−1 to 300 mA g−1 and 79.7% of initial capacity after 200 cycles. Moreover, the patterned devices based on the MX@Zn electrode achieve high energy and power densities of 348.57 Wh kg−1 and 1556 W kg−1, respectively, along with a capacity retention of 64% and Coulombic efficiency of 99% over 500 cycles. The high performance of MX@Zn is attributed to the high electrical conductivity and hydrophilicity of MXene and rapid ion diffusion through the 3D interconnected porous channels.