Nanostructured nickel ferrite: A liquid petroleum gas sensor

The present investigation deals with the synthesis of nanostructured nickel ferrite (NiFe 2 O 4 ) and their liquid petroleum gas-sensing characteristics. The 15–20 nm size nickel ferrite has been synthesized at 700 °C by a simple molten-salt route using sodium chloride as grain growth inhibitor. These nanoparticles exhibit significantly high response towards liquid petroleum gas (LPG) in comparison with ethanol vapor, hydrogen sulfide, ammonia and hydrogen. The gas response towards various gases at their 200 ppm concentrations is investigated at 200–450 °C. Different characterization techniques have been employed, such as differential thermal analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) to study the crystallite size, structure and morphology. The results suggest possibility of utilization of the nanostructured nickel ferrite, without addition of any precious metal ion, as the LPG detector.