The formation of lithium dendrites remains one of the biggest challenges of commercializing rechargeable lithium metal batteries. Here, we combine classical molecular dynamics simulations and first-principles calculations to study the possibility of utilizing modified graphdiyne film, which possesses intrinsic nanopores, as a stable "nanosieve" to reduce the lithium dendrites on anode. We find that through a mechanism resembling the hydraulic jump in fluid dynamics, graphdiyne film can enforce the concentration uniformity of lithium ions even under a highly non-uniform electric field and thus can induce a uniform nucleation of lithium metal. We further show that bare graphdiyne film can be gradually metalized by lithium metal, but the chlorination of graphdiyne significantly increases its resistance to the metalization and easily conducts the lithium ions. These properties together suggest that the chlorinated graphdiyne can potentially be used as a stable membrane to reduce the lithium dendrites in rechargeable lithium metal batteries.
Keywords: density functional theory; graphdiyne; lithium dendrite; lithium metal batteries; molecular dynamics.