Fabrication of CVD-grown graphene/Ag nanocomposites and its flexible sensor application

Abstract

The fabrication of designable CVD-grown few-layer graphene is a promising research area for enhanced device performance. In this study, the few-layer graphene was grown on Cu foil by chemical vapor deposition (CVD) method and functionalized with oxygen plasma treatment under controlled conditions, such as exposure time, input power and distance between the graphene and the plasma electrode. Oxygen plasma treated few-layer graphene (OPFG) results in high surface energy, leading to effectively attracting Ag+ ions in electrostatic interactions. Interestingly, the distribution of the metal nanoparticles increased with increasing the exposure time and their diameters were controlled by UV irradiation. Uniform Ag nanoparticles (Ag NPs) with ca. 9 nm diameter were successfully decorated on the graphene surface. Moreover, the Ag NPs/OPFG nanocomposite (AgNP–G) film has excellent mechanical bendability and durability in a flexible system. Furthermore, flexible hydrogen sensor of AgNP-G showed highly sensitive and reversible at room temperature (Minimum detection level, ca. 40 ppm)