Ethanol Sensors Based on Porous In(2)O(3) Nanosheet-Assembled Micro-Flowers

By controlling the hydrothermal time, porous In(2)O(3) nanosheet-assembled micro-flowers were successfully synthesized by a one-step method. The crystal structure, microstructure, and internal structure of the prepared samples were represented by an x-ray structure diffractometry, scanning electron microscopy, and transmission electron microscopy, respectively. The characterization results showed that when the hydrothermal time was 8 h, the In(2)O(3) nano materials presented a flower-like structure assembled by In(2)O(3) porous nanosheets. After successfully preparing the In(2)O(3) gas sensor, the gas sensing was fully studied. The results show that the In(2)O(3) gas sensor had an excellent gas sensing response to ethanol, and the material prepared under 8 h hydrothermal conditions had the best gas sensing property. At the optimum working temperature of 270 °C, the highest response value could reach 66, with a response time of 12.4 s and recovery time of 10.4 s, respectively. In addition, the prepared In(2)O(3) gas sensor had a wide detection range for ethanol concentration, and still had obvious response for 500 ppb ethanol. Furthermore, the gas sensing mechanism of In(2)O(3) micro-flowers was also studied in detail.