Carbon monoxide gas sensing performance of ZnO:Al thin films prepared using different solvent-stabilizer combinations

Carbon monoxide (CO) sensing ability of Al-doped zinc oxide thin films deposited using the sol-gel method was investigated for the first time employing different solvent-stabilizer combinations. The coating solutions for the films were prepared using different solvent-stabilizer combinations of two solvents, ethanol and 2-methoxyethanol and three stabilizers, monoethanolamine, diethanolamine and triethylamine (TEA). Structural, morphological and optical characterizations of the films were performed by X-ray diffraction, atomic force microscopy and UV-Visible spectrophotometer. Varying solvent-stabilizer combinations caused a considerable change in crystal size, surface roughness and transparency of the films. Furthermore, the results certainly unveiled that the combination of solvent and stabilizer significantly affected CO sensing properties of the films. A considerable high responsivity made the film consisting of 2-methoxyethanol-TEA combination highly suitable for CO gas detection.