Highly Sensitive Isopropanol Gas Sensor based on SnO 2 Nano-Flowers on Gold, Silver, and Aluminum Interdigitated Electrodes

In this research we have proposed a high selectivity Isopropanol gas sensor. The sensor shows significant resistance change only to Isopropanol gas. The synthesis method of flower-like SnO 2 nanostructures, the electrode material and design, and the optimized working temperature provide the high selectivity and high response of the sensor. The SnO 2 nanoflowers (NFs) have been synthesized in a two-step process as the gas sensitive layer. The sensor shows its best performance on Au interdigitated electrodes. The optimized working temperature is obtained at 150 °C. The proposed sensor has a high sensitivity, good repeatability, long-term stability and remarkable selectivity. The responses of the sensor to 100 ppm of isopropanol at 150 °C is 71 and the sensor is capable of keeping almost 96% of the initial response in a 40 d period.