Optimized NO2 and H2S gas sensor based on Si nanostructure incorporated gold nanoparticles

Abstract

Abstract In this study the gold nanoparticle are investigated to find the optimum condition to manufacturing NO2 and H2S gas sensor. The laser ablation approach been extensively used in preparation prepare gold nanoparticles on a porous silicon substrate using n-type silicon wafers. Used a Nd-YAG laser with a (1064, 532) nm wavelength, numbers of shot 500 and energies (600, 800, and 1000) mJ. The morphological and optical of the Au nanoparticles are studied using scanning electron microscope (SEM), photoluminescence spectroscopy (PL), reflection spectra and study sensing properties. In AuNPs quantum confinement has an effect as seen by a slight shift in the high-energy side of the PL spectrum's peak. With longer wavelengths and lower energies, the crystal with the shorter wavelength 532 nm has a greater refractive index. We observe that it has the largest visible wavelength 591 nm and peaks that are displaced to higher wavelengths. The H2S and NO2 gas sensors sensitivity, recuperation time, and reaction time built since prepared samples were all affected by changes in operation temperature. For each of the gases tested, the highest sensitivity was 30% in 532 nm and 155% in1064nm at 800 mJ for H2S gas while NO2 gas was around 24% in 532 nm and 23% in 1064 nm at 800 mJ. The Au nanoparticles produced by laser ablation create excellent gas sensing and might be a viable solution for industrial gas sensing applications.