Development of Enhanced 3D Flower Like Gd Doped NiO (GNO) Based LPG Gas Sensor

The Liquefied Petroleum Gas (LPG) sensing properties of pure NiO and Gd doped NiO nanoparticles (Gd - 1%, 3%, and 5%) have been prepared by polyol method and student. The prepared nanoparticles have been characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Ultraviolet-visible spectroscopy, X-ray Photoelectron spectroscopy to study the structural, morphological, optical properties and electronic state of the prepared nanoparticles. XRD reveals that NiO nanoparticles have average crystallite size of about 12 - 26 nm and 3D flower like morphology with 2 - 3 μm size was recorded and TEM images reveals the presence of quasi spherical particles with nanosheets of thickness about 20 - 30 nm range. Optical absorption is found to be in UV region and bandgap energy in the range 3 - 3.6 eV. XPS confirms the presence Ni²⁺, Ni³⁺ ions, Gd³⁺ ions and presence of two oxygen species lattice oxygen and adsorbed oxygen. LPG sensing properties have been studied in detail for both pure NiO and GNO nanoparticles (1%, 3%, 5% Gd doped NiO) and it demonstrate that doped Gd enhance the sensitivity response LPG gas at operating temperature range 160°C to 260°C.