Low-concentration H2S gas sensors based on MOF-derived Co3O4 nanomaterials

Metal-organic frameworks (MOF)-based gas sensors have garnered significant interest and are highly desirable for monitoring indoor air quality and mitigating various environmental reclamation challenges. Herein, we describe a unique approach for fabricating hydrogen sulfide (H2S) gas sensors based on MOF-derived cobalt oxide nanosheets (Co3O4 Ns) nanostructures. The surface morphology and porosity of the fabricated material were confirmed through comprehensive Brunauer-Emmett-Teller (BET) and electron microscopy analyses. Chemical composition and phase purity were identified using Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The sensor exhibited remarkable sensitivity towards hydrogen sulfide in the range of 0.5–100 ppm, reaching a maximum response of 1702.61 % at an operating temperature of 250 °C for 100 ppm H2S gas. Furthermore, the sensor demonstrated a detection limit of 500 ppb with a response rate of 78.22 %. A consistent stability over 30 days was observed, validating its suitability for real-world applications. The response and recovery times of the H2S gas sensors were assessed with τres/τrec = 63.56/103.34 s, offering valuable insights into their real-world applicability.