Aldehyde detection by ZnO tetrapod-based gas sensors

Zinc oxide (ZnO) tetrapods have been synthesized and prototypal gas sensors for volatile organic compounds (VOCs) have been realized with this sensing nanomaterial. Sensor characterization has been focused on aldehydes, such as acetaldehyde (or ethanal) and propionaldehyde (or propanal), whose detection at ppb levels is extremely important for monitoring environmental, domestic and food pollution, as well as for some sickness diagnosis and other medical applications. The response of gas sensor prototypes has been measured as a function of concentration, temperature, relative humidity and time. Good response values at ppb levels and some peculiar behaviours have been pointed out.