Abstract
In this work, we synthesized Sm2O3/ZnO/SmFeO3 microspheres by a hydrothermal method combined with microwave assistance to serve as a methanol gas sensor. We investigated the effect on the microstructure at different hydrothermal times (12 h, 18 h, 24 h, and 30 h), and the BET and XPS results revealed that the specific surface area and adsorbed oxygen species were consistent with a microstructure that significantly influences the sensing performance. The gas properties of the Sm2O3-doped ZnO/SmFeO3 microspheres were also investigated. With a hydrothermal time of 24 h, the gas sensor exhibited excellent sensing performance for methanol gas. For 5 ppm of methanol gas at 195 °C, the response reached 119.8 with excellent repeatability and long-term stability in a 30-day test in a relatively high humidity atmosphere (55–75% RH). Even at 1 ppm of methanol gas, the response was also higher than 20. Thus, the Sm2O3-doped ZnO/SmFeO3 microspheres can be considered as prospective materials for methanol gas sensors.
Highlights
Methanol is an important substance in the industry and daily life
There is no peak for ZnO observed in the X-ray diffraction (XRD) spectra because of the low concentration of ZnO; in Fig. 2b, elemental Zn is clearly observed in addition to the elements of Sm, Fe, and O, which are shown in the Energy dispersive X-ray spectroscopy (EDS) mapping
No other diffraction peaks corresponding to impurities were observed, which indicated that the sample was a mixture of Sm2O3 and SmFeO3 with high purity
Summary
Methanol is an important substance in the industry and daily life. It is an important raw material of many products such as formaldehyde, colors, and antifreeze. Direct methanol fuel cells (DMFC) are considered important alternative fuels for automotive manufacturers that are friendly to the environment [1]. It is necessary to quickly detect low concentrations of methanol gas at lower operating temperatures. Previous research on methanol gas sensors [3, 4] have not been satisfactory because of the high detection limit (> 50 ppm) and high operating temperature (> 275 °C). Few studies reported on the humidity stability issue of gas sensors
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
