Nanostructured SnO₂ Thin Films Based on a Convenient Chemical Deposition for Sensitive Detection of Ethanol

A specific matrix sensor that can operate at low temperatures and has a high sensing response is crucial for monitoring flammable VOC gases. In this study, a nanostructured SnO₂ thin film was successfully produced using a suitable chemical deposition method, and its sensing properties were comprehensively analyzed. The SEM images revealed that the thin film of the nanostructured SnO₂ is made up of two different sizes of broccoli-like structure nanoparticles. The sensor, which is based on this unique micronano structure, demonstrated a high sensing response (44), low operating temperature (200 °C), and fast response time (6s). Additionally, the nanostructured sensor exhibited excellent resistance to humidity interference and long-term stability. Moreover, DFT is employed to evaluate the electronic properties and to systematically explain the gas sensing mechanism of the nanostructured sensor based on the SnO₂ thin film.