Hydrothermal synthesis of ultrathin ZnO nanosheets and their gas-sensing properties

Gas-sensing performances can often be enhanced significantly once the size of sensing nanomaterials approaches a critical value of 15 nm. Here, we synthesize, by a simple hydrothermal method accompanied by the calcination process, ultrathin ZnO nanosheets with a thickness as thin as 10–13 nm. We find that the prepared zinc hydroxide carbonate precursor is largely agglomerated, yet transformed to the ultrathin ZnO nanosheets in a dispersive fashion after the calcination process. The as-prepared ultrathin nanosheets exhibit excellent gas-sensing functions to ethanol gas at the optimal temperature as low as 300 °C under the concentration of 50 ppm, rendering them a promising sensing material for the on-site detection of ethanol.