Ratiometric optical dual gas sensor for simultaneous detection of nitric oxide and oxygen intended for healthcare, biological, and biomedical applications

Developing efficient and reliable gas sensors for the simultaneous detection of multiple gases is paramount in various fields, specifically healthcare, biological, and biomedical applications. In this study, we present a novel ratiometric optical dual gas sensor based on perovskite quantum dots (PQDs) to detect nitric oxide and oxygen simultaneously. All dye molecules were excited using a 405 nm LED in the experimental setup. The results obtained from the experiments reveal that both the optical NO and O₂ sensors exhibit linear Stern–Volmer plots, and the sensitivities observed for NO and O₂ sensors were approximately 2.4 and 2.8, respectively. The response and recovery times of the optical NO sensor are 67 s and 69 s, respectively. O₂ sensor response and recovery times are 66 s and 68 s, respectively. In this work, the ratiometric optical dual gas sensing approach suppressed the effects of spurious fluctuations in the intensity of external and excitation sources.