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 V_GS=0 and 41% as in three terminal structure when V_GS=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.