▎ 摘　　要

NOVELTY - Composite structure comprises nanoparticles (NPs) deposited on a graphene substrate; and graphitic sheet. The NPs on the graphene substrate form a core-shell structure with the graphitic sheet encapsulating the nanoparticles. USE - The composite structure is useful for catalytic applications e.g. in fuel cells and dye sensitized solar cells. ADVANTAGE - The product is a unique encapsulating structure of graphene with NPs made by a simple LD (also called laser ablation) process. The NPs deposited on graphene spontaneously form a core-shell structure with a protective covering of graphitic shells around them. This significantly enhances their stability. The encapsulated structures also have excellent catalytic abilities. It ensures that the NPs are firmly attached to graphene and the encapsulating structure is robust enough for real life applications. The method is simple, scalable, and commercially suitable; provides efficient one-step synthesis of graphene and NP core-shell structure; improves the stability of the NPs; provides excellent catalytic ability; and forms a protective covering of graphite shells around NPs in one step, where the size and spatial distribution of NPs are uniform and controllable. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing an encapsulating structure which involves a one step process of depositing NPs onto a graphene substrate using pulsed laser deposition (PLD).