Pulsed-discharge-assisted assembly of Si quantum dots/graphene: Synthesis and mechanistic insights

Si/graphene nanocomposites, owing to their exceptional performance, hold promising applications in diverse fields like lithium-ion batteries, hydrogen storage, and sensors. This study presents a new and effective one-step green synthesis method for Si quantum dots (QDs)/graphene nanocomposites, accomplished through the pulsed discharge of Si strips in graphene oxide (GO) aqueous suspension. The microstructure and chemical composition of the recovered samples were meticulously characterized using multiple characterization methods. The results demonstrated the micro-morphology of recovered sample to be innumerable 2-nm-sized Si QDs uniformly distributed on the surface of GO. Furthermore, based on the previous investigation on pulsed discharge and the characterization results, the formation mechanism of Si QDs/graphene nanocomposites was proposed to be that the Si clusters in Si vapor produced from pulsed discharge deposited on the surface of graphene and formed Si QDs chemically bonded on the graphene. The stable structure, coupled with the uniform distribution of Si QDs of this nanocomposite, implies its significant potential application. This study also augurs well for this pulsed discharge synthesis method with a noteworthy candidate for further exploration and implementation.