Synthesis of porous spherical ZnO nanoparticles and measurement of their gas-sensing property

In present work, porous sphere-like and coralline-like ZnO nanoparticles (NPs) are synthesized by precipitation method at different calcination temperatures (400 and 450 °C). The temperature of calcinations plays an important role in formation of NPs morphology. A formation mechanism of porous sphere-like ZnO NPs is proposed. The response of gas sensing for different concentrations of acetone (1-10,000 ppm) at optimum temperature (310 °C) is shown. Besides, the ZnO NPs (400 °C) exhibits fast response and recovery time (average value is about 9 s and 6 s). These results demonstrate that the ZnO NPs (400 °C) can be used as an ideal candidate for fabricating high response (130-100 ppm) acetone sensor.