Three-dimensional graphene with charge transfer doping for stable lithium metal anode

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Lithium metal has attracted great attention as an ideal battery anode. However, non-uniform Li deposition leads to lithium dendrites, poor cycling performance, and safety hazards, thus hindering the commercial application of lithium metal anode. Herein, we present a new structure obtained by a facile chemical doping of 3-dimensional graphene (3DG) with Triethyloxonium hexachloroantimonate (OA) to guide uniform Li deposition. The created OA-3DG scaffold lowered the local current density with increased electrical conductivity and regulated Li deposition with enabled intermolecular interactions. All this facilitated homogenous Li nucleation and its controlled deposition. It was found that the initial homogenous nucleus layer regulated the following uniform Li growth, resulting in a dendrite-free anode. Benefiting from such favorable Li growth behavior, the doped 3DG endowed the lithium anode with long cycling stability of over 900 cycles along with a low overpotential (30 mV at a current density of 3 mA cm−2) in a symmetric Li/Li cell configuration. This significantly improved the performance of the created lithium-sulfur full cells, showing only 0.24% capacity reduction over 300 cycles.