Highly sensitive gas sensor based on Al-doped ZnO nanoparticles for detection of dimethyl methylphosphonate as a chemical warfare agent simulant

In this paper, we report a dimethyl methylphosphonate (DMMP) gas sensor using synthesized Al-doped ZnO nanoparticles (NPs) via a hydrothermal method. The average particle size of the Al-doped ZnO NPs is ∼25 nm. The single crystalline phase was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. The variation in the response of the Al-doped ZnO NP sensors within operating temperatures showed the highest response and recovery at 2 and 96 s, respectively, at 10 ppm in DMMP at 350 °C compared with undoped ZnO NP sensors. Our results showed remarkable sensitivity and selectivity of the Al-doped ZnO NPs sensor toward DMMP. Such increased O2 vacancies and surface reactions with small nanocrystals in the Al-doped ZnO NP sensors offer outstanding sensing performance for DMMP detection.