| 초록 |
A series of post-transition metals and semimetals in groups IIIA (Al, Ga, In), IVA (Ge, Sn, Pb) and VA (As, Sb, Bi) were introduced onto graphene nanoplatelets (GnPs) by mechano-chemical reaction. The selected metals have a lower electronegativity but a much larger covalent atomic radius than carbon. The effect of the electronegativity and atomic radius of the metalated GnPs (MGnPs, M = Al, Ga, In, Ge, Sn, Pb, As, Sb, or Bi) on the anode performance of lithium-ion batteries was evalusted. Among the series of prepared MGnPs, GaGnP, SnGnP and SbGnP exhibited significantly enhanced performance, including higher capacity, rate capability and initial Coulombic efficiency. Both the experimental results and theoretical calculations indicated that the optimum atomic size was more significant to the anode performance than electronegativity, allowing not only efficient electrolyte penetration but also fast electron and ion transport across the graphitic layers. |
