The ZnGa2O4 epilayer can only react with NO gas. The oxygen would be adsorbed on the surface and become adsorbed oxygen ions. NO gas molecules react with the oxygen ions and extract the conducting electrons which increase the device resistance. 

This technology is combined with the reading signal circuit, and the measured signal which can be transmitted by wifi, and then it uploads the data to the cloud. Even working in the harsh environment, the signal can be received in a safe place.

(1) Thin-film type and robust NO gas sensor with heater design and with low power.(2) Such high temperature resistant components are rarely seen in the market.(3) Portable and high temperature resistant, it can be placed in various environments.(4) Non-suspension sensor, stronger mechanical structure.(5) By connecting the circuit in series and measuring the change of partial pressure, NO concentration can be ontained immediately.(6) The element can maintain constant temperature operation.

In recent years, IoT and air pollution issues have received much attention. However the previous air pollution detection instruments are not only bulky but also expensive. Therefore, developing a new detection device is imperative. This sensor is highlighted with both portable and high-temperature resistant, which might be suitable for using in Internet of Vehicle technologies in the future.