Professor Azam Iraji zad Institute for Nanoscience & Nanotechnology Sharif University of Technology Tehran, Iran
Gas sensors based on low dimensional materials such as nanorods and nanosheets have demonstrated enhanced sensing properties due to large surface-to-volume ratio, significant electrical, physical and chemical properties. In this presentation our recent studies on sensing properties of vertically aligned metal oxides nanorodes like TiO2, CuO and ZnO will be reviewed. Graphene and MoS2 are attractive 2D materials in nanosensors due to possible modification of their electrical properties and easy preparation. We have used them in various forms including pristine, graphene oxide (GO) sheets, nanoribbon, 3D structure and composites using physical and chemical preparation methods. In addition to the standard sample electrical resistance measurement, we have applied sensing techniques like voltage change measurements in garphene based field effect transistor, frequency shift detection of single composite fiber, mass enhancement of sensitive porous layer on quartz crystals and change in scanning tunneling spectroscopy data after exposure to gases. We have focused on hydrogen as clean energy source, H2S as a highly toxic gas in oil industry and other useful gases detection including humidity.
1- Z. S. Hosseini, A.Iraji zad, A. Mortezaali, «Room temperature H2S gas sensor based on rather aligned ZnOnanorods with flower-like structures», Sensors and Actuators, B, 2015
2- R. Mohamadpour, H. Ahmadvand, A.Iraji zad, «A Novel Field Ionization Gas sensor based on Self-organized CuO Nanowire array», Sensors and Acutators A, 2014, 216, 202-206.
3- A. Esfandiari, A.Iraji zad, O Akhavan, S. Ghasemi, M. R. Golami, «Pd-WO3/reduced graphene oxide hierarchical nanostructures as efficient hydrogen gas sensors», International Journal of Hydrogen Energy, 39(15), 8169-8179 .
4- E. Asadian, S. Shahrokhian, A. Iraji zad, E. Jokar, «In-situ electro-polymerization of graphene nanoribbon/polyaniline composite film: Application to sensitive electrochemical detectionof dobutamine», Sensor and Actuator B, 2014, 196 ,pp. 582–588.
5- S. Fardindoost, S. Mohamadi, A. Iraji zad, R. Sarvari, P. Shariatpanahi, «Electromechanical resonators based on electrospun ZnO nanofibers», J. Micro/Nanolith. MEMS MOEMS, 2014, 13(4).
6- S. Hosseini, A. Iraji zad, F. Aghakhani Mahyari , Study MoS2 nanosheets by tunneling spectroscopy in preparation.