Chemically synthesized one-dimensional zinc oxide nanorods for ethanol sensing

摘要

One-dimensional (1D) zinc oxide (ZnO) nanorod (NR) based conductometric sensors have been developed and investigated towards ethanol vapor. The ZnO NRs were chemically synthesized onto alumina substrates with patterned interdigitated transducers (IDT) using a hydrothermal method. A seed layer of ZnO nanoparticles was pre-deposited onto the transducer substrates using a filtered cathodic vacuum arc (FCVA) technique. This seed layer was employed for the subsequent growth of NRs. Micro-characterization studies revealed that the grown ZnO has a rod like feature with an average diameter of 30 - 50 nm and an average length of 1.2 μm. The X-ray diffraction (XRD) analysis revealed that both ZnO seed layer and the NRs have a single crystal 1D nanostructure. The sensor performance was evaluated for ethanol vapor at operating temperatures from room to 330 °C. The study showed that the optimum operating temperature is in the range of 280 to 310 °C. At this temperature range, enhanced sensitivity, fast response and recovery with stable baseline were observed.