Bioinspired graphene-based nanocomposites and their application in electronic devices

Abstract

The increasingly popular flexible electronic devices, such as electronic papers, touch screens, roll-up displays, and wearable sensors, etc., require maintaining high performance, including mechanical and electrical properties, under repeatable deformation state. Graphene, as a two dimensional (2D) carbon nanomaterial with integrated high mechanical properties and electrical conductivity, could serve as the ideal building block for constructing functional materials in application of flexible electronic devices. There have been several attempts to use graphene-based nanocomposites in these devices. However, their assembly using traditional approaches, exhibit relatively poor mechanical and electrical properties, which largely limits the efficiency of these devices. Thus, it remains a great challenge to assemble microscopic graphene nanosheets into macroscopic high performance graphene-based nanocomposites. As known, the performance usually depends on the unique structure of materials, especially for the nanocomposites. Thus, it will be the next hot-topic that how to achieve the high performance flexible electronic device through designing and constructing the unique structures of graphene-based nanocomposites. Nacre, the “gold standard” for biomimicry with both high strength and toughness, has been the source of inspiration for designing many synthetic hybrid materials and nanocomposites. This is achieved through a precise architecture that resembles that of a brick wall, and the clever design of the interface. Compared to other approaches for constructing graphene-based nanocomposites, this bioinspired concept results in good dispersion, high loading and excellent interfacial interaction design. The resultant bioinspired graphene-based nanocomposites (BGBNs) demonstrate significant enhancement in mechanical and electrical properties. In this review, we summerize recent research progress on the BGBNs, following the research philosophy of discovery, invention, creation. Firstly, we analyze in detail the sophisticated interfacial architecture of natural nacre, which is responsible for its unique integration of high strength and toughness. Subsequently, we discuss the excellent mechanical and elertrical properties of graphene nanosheets. Then, we analyze and compare the effect of different interfacical interactions on the mecahnical and electrical properties of BGBNs. Furthermore, we discuss the synergistic effect from different interfacial interactions and building blocks for the fabrication of integrated strong and tough BGBNs. We highlight the fundamental physical properties of BGBNs, such as strength, toughness, and electrical conductivity. Specially, some other functions, including fatigue resistance, fire-retardant properties, etc., are also discussed. In addition, we also summarize the applications of BGBNs in flexible electronic devices, and discuss their challenges. Finally, we offer a perspective on the roadmap and target for BGBNs in the next 5−10 year as follows: (1) The essence of synergistic effect through different interfacial interactions and building blocks should be demonstrated and revealed by further theoretical simulation. (2) The tensile strength and stiffness of BGBNs can reach up to that comparable to carbon fiber reinforced composites, realizing application of BGBNs as structural materials in aerospace and aeronautics. (3) The integrated electrical and fatigue resistant properties should be simultaneously enhanced to satisfy the needs of flexible and wearable electronic devices. (4) Some simple, easy operation techniques will be explored for scaling up the fabrication of BGBNs, which could provide amount of BGBNs for practical applications in many fields.