Effect of Surfactant-Assisted Synthesis of ZnO Nanoparticles on Gas Sensitivity

To investigate the influence of nanoparticle size on sensor response, surfactants polyethylene glycol (PEG), and cetyltrimethylammonium bromide (CTAB) were used to facilitated the synthesis of ZnO nanostructures via a straightforward sol–gel technique. Structural properties were analyzed utilizing x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDX), and transmission electron microscopy (TEM). XRD analysis verified the establishment of wurtzite-structured ZnO. The surfactant significantly influenced the particle size management. Particles measuring, on average, 66 nm, 46 nm, and 37 nm were observed on TEM micrographs. Gas sensing experiments were conducted for various compounds, including acetone, ethanol, and ammonia, at a fixed concentration of 1000 ppm across various temperatures. Chemical sensing analysis indicated that the PEG-ZnO sensor exhibited a superior and selective response of 39.63% toward ethanol at a temperature of 250°C, in comparison with other sensors. The sensor responsiveness was significantly influenced by the particle size and form.