Functionalized carbon nanofiber interlayer towards dendrite-free, Zn-ion batteries

Although the intrinsic safety, low cost, and high theoretical energy densities have made the Aqueous zinc-ion batteries (AZIBs) to be a promising candidate in the application of energy storage fields. However, battery failure caused by the dendrite formation has become the major issue that disrupt their practical application. To solve that, herein, we report a unique interface strategy for regulating the interfacial electrodeposition kinetics and inhibiting dendrite formation through covering a N,O co-doped Carbon nanofiber (CNF) interlayers on Zn metal anode surface. Such CNF interlayers with robust zincophilicity can effectively capture the Zn ions, and guiding the regular Zn electrodeposition in the anode-electrolyte interface, which have been demonstrated by both theoretical calculation and experimental results. Significantly, the electrochemical tests confirmed that the cell modified with CNF interlayers exhibits a high Zn plating/stripping reversibility with a low nucleation overpotential. Notably, the modified cell enables steadily operating for 1200 h with a low overpotential of 59.5 mV at a high current density of 5 mA cm−2 (1 mAh cm−2). Moreover, the rate capability and cyclic stability of Zn-MnO2 full battery can be greatly improved after covering the CNF interlayers on the Zn metal anode surface. This work is highly expected to provide a new route to enable dendrite-free Zn metal anodes and high-performance AZIBs.