Highly sensitive and selective ethanol gas sensor based on Ga-doped NiO nanoparticles

Abstract

We have systemically examined the impact of Ga doping on structural, optical, and ethanol sensing properties of NiO nanoparticles. X-ray diffraction study demonstrated cubic structure of pure as well as Ga-doped NiO nanoparticles. Brunauer Emmett Teller results indicated that Ga doping increases the surface area of NiO. Fascinatingly, dopant altered the surface morphology of NiO from micro rods to large area nanoparticles which eventually improved the sensing properties of Ga-doped NiO nanoparticles. Raman and photoluminescence spectroscopy indicated huge number of defects in 3% Ga-doped NiO nanoparticles. The catalytic effect of Ga reduced the activation energy of Ga-doped NiO which further improved sensing properties of doped samples for 50\xa0ppm of ethanol. The improvement in sensor response and selectivity of 3% Ga-doped NiO sensor to ethanol is accredited to larger surface area, augmented defect concentration, and excellent catalytic effect of the sensor. The sensing results revealed that 3% Ga-doped NiO sensor was able to detect even 10\xa0ppm of ethanol. The astonishing response of 3% Ga-doped NiO nanoparticles suggested that they can be utilized for producing high performance ethanol gas sensing devices.