Formation mechanisms of multiple Si/graphene nanocomposites through underwater pulsed discharge using different wire arrangements

Abstract

Si/graphene nanocomposite is regarded as an advanced lithium-ion anode material, attributable to its advantageous microstructure and exceptionally high theoretical specific capacity. This study demonstrates a novel approach for the preparation of Si/graphene nanocomposites, achieved through the pulsed discharge method employing graphite and Si strips as precursors. We devised two distinct “one-step” synthetic routes through pulsed discharge of different wire arrangements. The characterization results of the obtained samples unveiled the presence of Si/graphene composite and Si@carbon layer composite. In addition, the formation mechanisms of Si/graphene nanocomposites have been proposed, different wire arrangements lead to the different energy deposition processes, inducing different robust mechanical and thermal effects on the products. The formed Si clusters either deposit on the surface of exfoliated graphene or become encapsulated within curling graphitic layers, forming a core@shell structure. This work not only presents a straightforward and innovative approach for synthesizing Si/graphene nanocomposites but also contributes valuable insights into the underlying mechanisms governing their formation.