A Low-Cost Ion Selective Nitrate Sensor Based On Self-Assembled Graphene Microelectrode Arrays

This paper reports a novel micro sensor which used self-assembled graphene microelectrode arrays to selectively detect nitrate solutions. Graphene microelectrode arrays were utilized to sensitively detect the change of ion density. Self-assembly technique provided an effective 3-dimensional platform for sensing applications. An ion selective ionophore film was deposited upon graphene surface to make the sensor selectively sensitive for nitrate ions. As a result, the self-assembled graphene microelectrode arrays showed superb sensing performance for pH with advantages of low cost and label free. After decorating nitrate ionophore film, the selective sensor demonstrated high sensitivity and reproducibility for nitrate ions. This simple, low-cost and selective sensor could lead to wide applications in environmental monitoring.