High performance acetone sensor based on ZnO nanorods modified by Au nanoparticles

Modification with Au nanoparticles on the surface of semiconductor metal oxide (SMO) is a simple and effective mean to improve the sensing performance of pristine SMO sensor. ZnO nanorods are prepared via a simple precipitation reaction and subsequently modified by catalytic Au nanoparticles with effect on the surface through an ammonia deposition method. The gas response of sensor based on ZnO nanorods modified by Au nanoparticles is improved by 6.6 times to 100 ppm acetone at the optimal operating temperature of 172 °C, which is reduced from 219 °C for pristine ZnO sensor. Meanwhile, the response/recovery time is shortened to 1 s/20 s from 13 s/29 s. In addition, the sensing enhancement mechanism can be attributed to the electronic and chemical sensitization effects of Au nanoparticles.