Zinc oxide thin films deposited by sol–gel spin-coating technique for propane and carbon monoxide sensing applications

Resumen. Undoped zinc oxide (ZnO) films were deposited on soda-lime glass substrates by utilizing sol–gel spin coating method. Zinc acetate dihydrate, 2-metoxietanol and monoethanolamine were used as precursor, solvent and surfactant, respectively. XRD analysis confirms the ZnO wurtzite structure with (002) as the preferential orientation. SEM studies show the formation of porous and spherical grains with a grain size distribution from 20 to 60 nm. Raman spectroscopy confirms the crystallization and structural disorder of all ZnO sensors. Sensing responses of all ZnO films were obtained for both carbon monoxide (CO) and propane (C3H8) gases at different gas concentrations and operating temperatures. The highest sensing responses of ~ 35 and ~ 1400 were obtained for films deposited at 4000 rpm and exposed a CO and C3H8, respectively. The behavior of sensing responses is explained in detail based on the structural and morphological properties and the improvement in the structural properties and sensing responses is explained based on the spin coater rotation speed.

Autores. Arturo Maldonado Álvarez
Revista J Mater Sci: Mater Electron
https://doi.org/10.1007/s10854-024-12502-x