Room temperature ethanol sensor based on ZnO prepared via laser ablation in water

Abstract

The present work reports on room-temperature ethanol sensing performance of ZnO nanospheres and nanorods prepared using pulsed laser ablation in water. Nanosecond and millisecond lasers were used to prepare ZnO nanomaterials with hexagonal wurtzite crystal structure. The two contrasting nanostructures were tested as gas sensors towards volatile compounds such as ethanol, ammonia, and acetone. At room temperature, devices based on both ZnO nanomaterials demonstrated selectivity for ethanol vapor. The sensitivity of nanospheres was somewhat higher compared to that of nanorods, with response values of ∼19 and ∼14, respectively, towards 250 ppm. Concentrations as low as 50 ppm could be easily detected.