Development of ultrafast room temperature LPG sensor using Fe2O3/PVP nanocomposite

In this paper, polyvinylpyrrolidone (PVP) polymer-coated iron oxide (Fe2O3) nanocomposite was synthesized using the sol-gel method. The effects of PVP coating on the Fe2O3 nanocomposite were analyzed by X-ray diffractometer (XRD), transmission electron microscope (TEM), Raman spectrophotometer, Fourier transform infrared spectrophotometer (FTIR) and UV-visible spectrophotometer. The XRD data reveal the formation of an iron nanoparticle having a minimum crystallite size 4 nm. TEM morphology shows the presence of spherical iron oxide nanoparticles ranging from 5 to 7 nm is coated with the PVP polymer. The prepared sample was also analyzed with Raman spectroscopy and found that no impurity was found in the sample. FTIR bands at 553 cm(-1) confirm the Fe-O stretching mode of Fe2O3. The bandgap has been calculated by UV-visible spectroscopy and found to be 6.4 eV, and a higher bandgap is favourable for gas sensing property. A photo-resist spinner has been used to prepare a thin film of synthesized nanomaterial. Further, this film has been successfully employed as a room temperature liquefied petroleum gas sensor, and the sensor response was found to be 1.004 at 1250 ppm. The minimum response and recovery times of the fabricated film sensor have been found as 20 s and 23 s, respectively.

Automated summary

In this study, polyvinylpyrrolidone-coated iron oxide nanocomposite was successfully synthesized and characterized. The nanocomposite exhibited a small crystallite size and a PVP coating, with no impurities detected. A thin film of the synthesized material was prepared and used as a gas sensor, demonstrating short response and recovery times.