Room-temperature SnO2-based sensor with Pd-nanoparticles for real-time detection of CO dissolved gas in transformer oil

• Published in: Materials chemistry and physics Vol. 311; p. 128576
• Main Authors: Simões, Agnes Nascimento, Lustosa, Glauco Meireles Mascarenhas Morandi, de Souza Morita, Eugênio, de Souza, André Nunes, Torres, Floriano, Bizzo, Waldir Antonio, Mazon, Talita
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-01-2024
• Subjects: Carbon monoxide; Dissolved gas analysis; Gas sensor; Tin dioxide; Transformer oil; Dissolved gas analysis; Tin dioxide; Gas sensor; Carbon monoxide; Transformer oil
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2023.128576

SnO2 and Pd nanoparticles (NPs) were synthesized by hydrothermal method and sol-gel, respectively. A paste formed by tin dioxide NP and PVDF was deposited as thick film on alumina substrates through screen printing method and decorated with Pd on surface. The morphology and structure of the samples were investigated by Scanning Electronic Microscopy (SEM), X-Ray Diffraction (XRD) and Raman Spectroscopy. The SEM images show SnO2 nanoparticles with rod shapes and 10–15 nm of diameter size and Pd spherical nanograins with 15–35 nm of diameter. XRD analysis identifies rutile structure for SnO2 powder and cubic structure for Pd NP. To investigate the gas sensing property of the SnO2:Pd nanostructured composite, the electrodes were immersed in an insulating mineral oil, in a closed system where different gas concentration of monoxide carbon (CO) were injected into the headspace and then dissolved into oil, according to Ostwald coefficient. All measurements were carried out at room temperature using a concentration range from 50 to 500 ppm (in headspace). The electric characterization showed that our SnO2-based sensor had change its resistance in a lower concentration of dissolved gas, ∼13.3 ppm of CO, into the mineral oil, indicating its potential use for real time monitoring of transformers.
•Synthesis of SnO2 nanostructures decorated with Pd-Nanoparticles.•Development of immersed sensor board for power transformers.•CO detection sensitivity less than 20 ppm dissolved into oil at room temperature.•Efficiency for real-time monitoring through in situ electrical measurements.•Potential industrial applications for failure prevention of equipment and hazards.