Reducing lithium deposition overpotential with silver nanocrystals anchored on graphene aerogel

Abstract

Li metal as an anode for high-energy-density batteries is actively pursued due to its high specific capacity and ultralow electrochemical potential. Unfortunately, Li dendrite growth might induce a short circuit creating safety hazards that limit the practical applications of Li metal anode batteries. Herein, a novel anode of graphene aerogel (GA) decorated with silver nanocrystals (AgNCs@GA) is reported for effective suppression of lithium dendrite growth and improvement in coulombic efficiency at various current densities. This improved performance is attributed to AgNCs. This loaded AgNCs with high Li affinity serve as Li deposition sites, which deeply reduce the overpotential of Li nucleation and electrodeposition. Therefore, it successfully realizes stable Li deposition/stripping processes with enhanced coulombic efficiency at various current densities and areal capacities. The pre-lithiated AgNCs@GA is evaluated as an anode in a Li battery and demonstrates remarkable performance in comparison with a commercial lithium foil.