Polypyrrole-Bonded Quaternary Semiconductor LiCuMo₂O₁₁–Graphene Nanocomposite for a Narrow Band Gap Energy Effect and Its Gas-Sensing Performance

Abstract

In this study, we demonstrate the fabrication and characterization of a new quaternary semiconductor nanocomposite of LiCuMo₂O₁₁/graphene oxide/polypyrrole (LCMGP) via a hydrothermal method and testing of an NH₃ and H₂SO₄ sensor operating in gaseous states at room temperature. We used X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to characterize the properties of LCMGP nanostructures. Our sensor is capable of detecting NH₃ and H₂SO₄ and quantifying their concentration in the gas flow. These results have been confirmed by exposing the sensor to different concentrations of NH₃ and H₂SO₄ (100-1000 ppm). The obtained results confirm the exceptional sensing properties of the graphene-polymer-combined quaternary semiconductor nanocomposite related to the oxidation-reduction process that can be used for detection, identification, and quantification purposes.