Synthesis of ZnO Nanoparticles With a High Specific Surface Area Using Gum Arabic Biotemplate for NO₂ Gas Sensor Detection

In this study, we synthesized microstructures using a straightforward hydrothermal method and extensively characterized them using various analytical techniques. Such as X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscope (AFM), and X-ray photoelectron spectrum (XPS) have been used to verify the crystal phase, morphology, and composition. Following this characterization, we assessed the nitrogen dioxide (NO2) sensing performance of the fabricated sensors. Surprisingly, at a low operating temperature of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$110~^{\circ }$ </tex-math></inline-formula>C with a response of 1736.03%, the gum arabic (GA)/zinc oxide (ZnO) microstructures exhibited remarkable selectivity, displaying robust repeatability (12 cycles) and stability (22 days) in their response. Furthermore, our findings revealed that introducing GA as a biocompatible substrate significantly increased surface oxygen vacancies, acting as additional adsorption sites for NO2. Consequently, this improvement enhanced gas detection performance and demonstrated exceptional selectivity in practical applications. Upon comparison with other literature, we observed the maximum response value at a low concentration in the ppb level.