TiO2-GO Field Effect Transistors for Amplified Ethanol Sensing

In this work we have proposed p-TiO2-GO nanocomposite field effect transistor based ethanol sensor. p-type TiO2 nanoparticles was prepared by sol-gel method and mixed with 2 wt% aquas solution of graphene oxide (GO) and sonicated for 30 min. The nanocomposite was prepared in combination of 5 vol% p-TiO2 nanoparticles with 95 vol% GO. The morphological and structural characterizations of developed nancomposite were carried out with field emission scanning electron microscopy (FESEM) and Raman spectroscopy techniques, respectively. The p-TiO2-GO field effect transistor (FET) sensor showed a response magnitude of 6% in terminal structure when VGS=0 and 41% as in three terminal structure when VGS=0.65 V in the exposure of 100 ppm ethanol at 100°C. The p-TiO2-GO FET showed maximum ~7 times amplification in sensitivity due to application of positive gate voltage.