A 2D Metal Oxide Nanosheet as an Efficient Additive for Improving Na-Ion Electrode Activity of Graphene-Based Nanocomposites

Abstract

An efficient way to improve the Na-ion electrode activity of graphene-based nanocomposite is developed by employing exfoliated metal oxide nanosheet as an additive. The titanate-nanosheet-incorporated Na-SnS₂ -reduced graphene oxide (rG-O) nanocomposites can be synthesized by the electrostatically derived restacking of the colloidal mixture of SnS₂ , rG-O, and titanate nanosheets with the Na⁺ cation. The incorporation of titanate into the Na-SnS₂ -rG-O nanocomposites is effective in improving the nanoscale mixing of component nanosheets and the porosity of the composite structure. The resulting nanocomposites deliver superior discharge capacities and rate properties to the titanate-free nanocomposite. The universal applicability is further confirmed by MoS₂ -rG-O nanocomposites upon the addition of titanate. This study highlights that the exfoliated metal oxide nanosheet can be used as an efficient additive for graphene-based nanocomposites to explore Na-ion electrode materials.

Keywords: Na-ion batteries; composite materials; graphene; metal chalcogenide; nanosheets.