Gas Sensing Properties of Al-doped ZnO Thick Films Prepared by Sol-Gel Method

摘要

Al-doped ZnO thick films were prepared by sol-gel method, then which were annealed respectively at 500°C, 700°C and 900°C. The structure of these samples was studied by XRD and SEM. Moreover, the influence on gas sensing properties of the films, result from different Aluminum-doped concentration and different annealing temperature, were mainly researched. Results showed that after 700°C*3h annealing, 2.9wt% Al-ZnO possessed excellent selectivity to acetone (volume fraction: 4.0×10-1). The maximal sensitivity of the gas sensor is 7779, the best operating temperature is 162°C, and the response-recovery time was Is.