Gas sensing properties of graphene oxide loaded with SrTiO3 nanoparticles

• Published in: Journal of alloys and compounds Vol. 941; p. 169011
• Main Authors: Kacem, Khaoula, Casanova-Chafer, Juan, Ameur, Sami, Nsib, Mohamed Faouzi, Llobet, Eduard
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.04.2023
• Subjects: CO2; Gas sensor; Graphene oxide; NH3; NO2; SrTiO3 perovskite; NO2; NH3; Graphene oxide; Gas sensor; SrTiO3 perovskite; CO2
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.169011

This paper reports a straightforward and inexpensive method for the fabrication of gas sensing devices based on graphene oxide (GO) synthesized by a modified Hummer’s method and decorated with strontium titanate perovskite (SrTiO3). The active layers developed were employed for the detection of hazardous gases such as NO2, CO2, and NH3. The physical and chemical properties were also analyzed using various experimental techniques including field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and Raman spectroscopy. Repeated response and recovery cycles were applied in the detection of nitrogen dioxide (NO2), carbon dioxide (CO2), and ammonia (NH3). Accordingly, the gas sensing study reveals that decorated GO exhibits a high response towards NO2 at an operating temperature of 100 °C with good sensitivity (up to 4-fold higher than that of pristine GO) and highly improved selectivity. Additionally, the effect of ambient humidity was tested for NO2, demonstrating that GO/SrTiO3 sensors show a good immunity to humidity cross-sensitivity. Lastly, a gas sensing mechanism was schematically proposed and discussed. These findings prove that the functionalization of GO with SrTiO3 can overcome the limitations of GO-based sensors by enhancing their adsorption capability of gas molecules and their sensitivity towards target gases. •Graphene oxide was loaded with nanoparticles of strontium titanate via impregnation.•The manomaterial is used for detecting harmful gases at ppb- ppm levels under dry or humid conditions.•Loaded graphene oxide shows a 4-fold higher response to NO2 than bare graphene oxide.•The gas sensing mechanism of the hybrid nanomaterial for nitrogen dioxide is discussed.