Document Type : Research Paper

Author

Directorate of Materials Research, Ministry of Science and Technology, Baghdad, Iraq

Abstract

In this research, ZnO nanorods were utilized as gas sensor materials for detecting toluene vapour and hydrogen gas prior to and following the use of Zeolitic imidazolate frameworks-8 (ZIF-8) as gas filter. On porous Al2O3, ZIF-8 was deposited and the thickness was 200 nm. Scanning electron microscope (SEM), XRD, and gas sensing tests were used to examine the material characteristics regarding ZIF-8 and ZnO. Thin films' sensitivity and selectivity to different gases such as C7H8 and H2 were also investigated. Comparing with pristine ZnO nanorods sensor, ZnO sensor is highly sensitive to C7H8 and H2, whereas the nanostructure regarding ZnO with ZIF8 as sensor has significantly selective response to the hydrogen gas. The small pore aperture of the ZIF-8 explains this behavior as H2 molecules could rapidly spread across ZIF-8 network and reach the surface of the ZnO.

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