Porous In2O3 nanorods fabricated by hydrothermal method for an effective CO gas sensor

In this study, porous In2O3 nanorods were fabricated by a simple low-cost hydrothermal method, followed by heat treatment, for use as an effective CO gas sensor. Material characterization by some advanced techniques demonstrated that high quality In2O3 nanorods, of about 10 nm in diameter and 40 nm in length, were obtained. The In2O3 nanorods had a porous structure composed of many nanopores of about 1.9 nm in size. The sensor based on the porous In2O3 nanorods was fabricated using a drop-coating technique. The sensor showed the best gas sensing performance at a working temperature of 350°C with a response value of about 3.5 for 400 ppm CO. The selectivity and stability of the sensor were also studied, and the results showed that the device had excellent stability and a high selective capability to detect CO over H2, NH3, toluene, ethanol, acetone, isopropyl alcohol, CO2 and CH4 gases.