Integration of ZnO and Au/ZnO Nanostructures into Gas Sensor Devices for Sensitive Ethanolamine Detection

Zinc oxide hollow microspheres (ZnO HMPs) were synthesized through a simple carbon microsphere-assistant soaking route following the annealed process. Configured as a resistor-type gas sensor, the as-synthesized HMP sensor exhibited good response to ethanolamine. After Au nanoparticles were loaded, the sensing performances of the Au-modified zinc oxide (Au/ZnO) products were dramatically increased. The experimental results indicate that a high response of 68.786 is measured under 100 ppm ethanolamine gas at an optimal operating temperature of 240 °C. Fast response time (13 s) and recovery time (24 s) to 500 ppb of gas phase ethanolamine at the operating temperature are recorded. The limit of ethanolamine detection was as low as 200 ppb. Additionally, the sensor device exhibited good selectivity and stability. Furthermore, the mechanism of the 2% Au/ZnO sensor performance is also discussed.