New SH-SAW sensor based on sensitive graphene oxide layers for gases or liquids detection

Poster presented at the XXX Trobades Científiques de la Mediterrània, Josep Miquel Vidal, Graphene and related materials: production, characterization, applications. 15th - 17th october, 2014, Menorca (Spain).
Surface acoustic wave (SAW) sensors have high sensitivity, high stability and signal easy to process. In order to achieve high sensitivity in SAW sensors, it is essential to confine the maximum amount of acoustic energy near the surface of the substrate and minimize wave scattering into the bulk of the substrate. These devices are based on the excitation of shear horizontal surface acoustic waves (SH-SAW) in a piezoelectric substrate, guided by a layer deposited over it and can be used for gas/liquid detection. A key issue in their design is the choice of sensitive layer. Gaphene oxide (GO) is a very attractive nanomaterial for sensor applications because it combines 2D structural features of graphene and the presence of oxygen-containing functional groups (mainly, epoxide, hydroxyl and carbonyl groups), which can potentially interact with a great variety of analytes. Besides, GO can act as a substrate and to be interfaced with various biomolecules and cells, therefore these SH-SAW sensors could be also used to biological detection. In this work, we present the first results obtained with a GO SH-SAW sensor for the detection of (CWA) simulants .