Super high sensitive plate acoustic wave humidity sensor based on graphene oxide film
Iren E Kuznetsova1, Vladimir I Anisimkin2, Sergei P Gubin3
1Kotelnikov Institute of Radio Engineering and Electronics of RAS, Moscow 125009, Russia; Management School, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093, PR China.
Abstract:
The changes of density and elastic modules due to water vapor adsorption are measured for graphene oxide film at room temperature. Dominant mechanism for acoustic wave humidity sensing by the film is shown to be related with variation of its electric conductivity. Basing on the data, super high sensitive humidity sensor employing high-order Lamb wave with large coupling constant, standard lithium niobate plate, and graphene oxide sorbent film is developed. The minimal detectable level of the sensor is as low 0.03% RH, response times are 60/120s, and reproducibility is ±2.5%. The sensor is completely selective towards H2, CO, CH4, NO, O2.
