Fabrication of nanobeads structured perovskite type neodymium iron oxide film: Its structural, optical, electrical and LPG sensing investigations

Nanocrystalline neodymium iron oxide (NdFeO3) has been synthesized through sonication assisted precipitation technique. X-ray diffraction analysis reveals the formation of NdFeO3 having orthorhombic structure (perovskite type). The minimum crystallite size was found 12 nm. Energy dispersive X-ray analysis confirms the elemental compositions of the synthesized material. The optical band gap of NdFeO3 was found 3.8 eV using the Tauc plot. Surface morphological investigations show the uniform and bead structured surface morphology. LPG (liquefied petroleum gas) sensing properties of NdFeO3 in the form of solid state pellet as well as thin film were investigated. These investigations have been focused on the response characteristics of the fabricated LPG sensor. The mechanism of LPG adsorption on the surface of sensing film has been discussed. Results illustrate that the fabricated film sensor was superior in comparison to the pellet sensor. The response and recovery times of the film sensor were similar to 60 and 90 s, respectively. Electrical behavior of NdFeO3 in air was also investigated. In addition, activation energies were estimated. The fabricated LPG sensor has high sensitivity, low response and recovery times, good reproducibility, operable at room temperature and simple construction, so it is promising. (c) 2012 Elsevier B.V. All rights reserved.