Hydrothermal synthesis of a bimetallic metal–organic framework (MOF)-derived Co3O4/SnO2 composite as an effective material for ethanol detection

Abstract

This study utilized a hydrothermal method and air calcination to prepare a bimetallic metal–organic framework (MOF) derived Co₃O₄/SnO₂ nanocomposite material, which was employed as a sensing material for ethanol detection. The structure, elemental composition, and surface morphology of Co₃O₄/SnO₂ nanocomposite materials were defined using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Compared to SnO₂ nanoparticles derived from metal–organic frameworks, the bimetallic metal–organic framework-derived Co₃O₄/SnO₂ nanocomposite material exhibits significantly superior ethanol sensing performance. At 225 °C, the response value (R = R_a/R_g) to 100 ppm ethanol is 135, demonstrating excellent repeatability, selectivity and stability. Gas sensitivity assessment findings indicate that the 3 at% (Co/Sn) Co₃O₄/SnO₂ nanocomposite is an excellent gas sensing material, providing strong technical support for ethanol detection and environmental monitoring.