Flame aerosol reactor synthesis of nanostructured SnO2 thin films: High gas-sensing properties by control of morphology

Tin dioxide (SnO2) thin films were deposited on commercial alumina chips using a flame aerosol reactor (FLAR) system. The morphology of the thin films was controlled by changing various parameters, such as precursor concentration, burner–substrate distance, and deposition time. Three typical morphologies of the thin films were achieved, i.e., columnar, column–granular, and granular structures. The as-prepared thin films with columnar structures demonstrated improved sensing performance to ethanol vapor, due to their preferred orientation, single crystal phase, and unique morphology.