Graphene-based nanocomposites sensors for detection of ammonia.

Over the last years, a wide variety of nanomaterials have been utilised for the design of highly efficient sensors to detect ammonia (NH3) accurately. Discovery of graphene has dramatically accelerated studies on fabrication of inexpensive electrode materials due to its unique features such as high specific surface area, high carrier mobility, high electrical conductivity, flexibility and optical transparency. Graphene and its derivatives can be readily combined with a variety of inorganic-based nanoparticles such as noble metals, metal oxides and semiconducting, as well as conducting polymers to develop NH3 sensor with excellent sensitivity and very low detection limit. This paper overviews graphene nanocomposite gas sensors as emerging NH3 sensing platforms for the detection of a wide range of NH3 concentration with improved sensitivity, selectivity and a low response and recovery times. Various sensing mechanisms of functionalised graphene nanocomposite gas sensors are explained and compared. Possible opportunities and perspective applications of the graphene NH3 sensors are also presented. [ABSTRACT FROM AUTHOR]