Functionalized and environment-friendly carbon materials for flexible and wearable electronic devices

Recently, more and more attention are drawn to flexible and wearable electronics due to their potentiality in various industries, including sensing and healthcare. In flexible and wearable electronics fabrications, carbon materials are believed to be an ideal choice because of their outstanding physical and chemical properties like conductivity, flexibility, and stability. This review concentrates on two kinds of carbon materials, carbon nanotubes (CNTs) and graphene, widely studied and implemented in the flexible and wearable electronics industry. CNTs are firstly discussed with their properties and an overview of their synthesis methods. Following this, the manufactural approaches to synthesis CNTs are reviewed from both dry chemistry and wet chemistry perspectives. Then, graphene's potential and synthesis methods are reviewed, with advanced achievements done in recent studies on flexible and wearable devices. In addition, various applications of CNTs and graphene in flexible and wearable electronics are discussed in detail. Finally, the expectation and development directions of desirable materials in the field are discussed.