Construction of CdIn2O4/In2O3 composites containing n-n heterojunctions with excellent nitro-alkanes sensing performance

Developing a technique for the detection of nitro-alkanes, which are explosive and toxic, is vital. However, it is hard to selectively detect these compounds at low concentrations for early leakage warning. Here, a nanocomposite material was prepared to promote electron transfer and enhance the content of chemically absorbed oxygen by creating an n-n heterojunction between CdIn 2 O 4 and In 2 O 3 , leading to an enhanced response, shortened response time and reduced working temperature. As a result, the best sensor was found to exhibit an ultra-high response of 78 to 10 ppm nitropropane with quite a low detection limit of 50 ppb at 100 °C. Furthermore, the designed sensor was nearly insensitive to ethanol, acetone, hydrogen, CO, methanol, toluene and methane. Presently, the sensor demonstrated the highest response among those studied in previous investigations.