Spray synthesis of rapid recovery ZnO/polyaniline film ammonia sensor at room temperature

As an excellent room temperature sensing material, polyaniline (PANI) needs to be further investigated in the field of high sensitivity and sustainable gas sensors due to its long recovery time and difficulty to complete recovery. The ZnO/PANI film with p–n heterogeneous energy levels have successfully prepared by spraying ZnO nanorod synthesized by hydrothermal method on the PANI film rapidly synthesized at the gas—liquid interface. The presence of p–n heterogeneous energy levels enables the ZnO/PANI film to detect 0.1–100 ppm (1 ppm = 10⁻⁶) NH₃ at room temperature with the response value to 100 ppm NH₃ doubled (12.96) and the recovery time shortened to 1/5 (31.2 s). The ability of high response and fast recovery makes the ZnO/PANI film to be able to detect NH₃ at room temperature continuously. It provides a new idea for PANI to prepare sustainable room temperature sensor and promotes the development of room temperature sensor in public safety.