Design of a graphene-based core–shell structure for the improvement of photothermic performance

Abstract

Owing to its unique photothermal initiation mode, laser ignition has been considered as one of the most promising initiation methods for the next generation of initiators and pyrotechnics. Unfortunately, the wide application of laser ignition has been prevented by its stubbornly high initiating energy. With the benefit of a unique two-dimensional (2D) layered structure, graphene oxide has been reported to be effective in reducing the initiating energy for laser ignition. However, due to the intrinsic drawbacks of graphene oxide, a further reduction in initiating energy is still a challenging task. Notably, a core–shell structure is a very attractive framework for the design of functional materials owing to its versatility in regulating the properties of diverse components. Herein, we have designed a graphene-based core–shell structure by the in-situ formation of a uniform coating layer on the surface of individual graphene oxide sheets. The 3-aminophenol/formaldehyde resin coating layer will contribute to increases in light absorbance and energy density, which endow the surface coated graphene oxide with much improved photothermal properties. Accordingly, through use as the energy converter of the laser ignition device, a freestanding membrane of surface-coated graphene oxide is able to effectively enhance the temperature rise during laser irradiation and reduce the initiating energy for laser ignition. Such a strategy of designing a suitable core–shell structure will not only serve to further improve laser ignition, but also shed light on the development of 2D materials in different fields.