Investigation of the stability of QCM humidity sensor using graphene oxide as sensing films

In this paper, the stability of quartz crystal microbalance (QCM) humidity sensor based on graphene oxide (GO) films is investigated by impedance analysis method. The stability characteristic of GO based QCM sensor during humidity detection is studied and quantitatively compared with conventional polymer coated QCM sensor. It is found that the stability of GO based QCM sensor is significantly higher than that of polymer coated QCM sensor at any humidity condition. Especially at high humidity points, the advantage of the stability of GO based QCM sensor becomes more prominent, the quality factor of GO based QCM sensor is nearly 25 times greater than that of polymer based QCM sensor. Further, a possible mechanism of the experimental phenomena is suggested. This research provides a simple and effective approach to construct high stability QCM chemical sensor by using GO based materials as the sensing layer.