Janus Membranes with Graphene Meshes and ZnO Rods for Controlling Dendritic Growth in High-Performance Li Metal Anodes

Abstract

We present a design strategy for Li metal anodes that can circumvent unwanted Li dendrite growth by inducing position-selective and direction-selective deposition of Li. To enable this, we propose the use of a multilayer graphene mesh (MLGM) with the side facing the current collector decorated with lithiophilic catalysts of ZnO rods. Owing to the geometric configuration, Li continues to grow in the opposite direction of the counter electrode, that is, toward the current collector. This unusual Li growth depresses the formation of dead Li and prevents a short circuit occurring between the anode and cathode. As a result, the proposed anode showed a significant improvement in cycling performance with no capacity loss over 500 cycles, superior rate characteristics with a Coulombic efficiency higher than 99%, and a low overpotential of 14 mV at 5 mA cm-2.