Synthesis, Characterization, and Gas Sensing Properties of In-doped ZnO Nanopowders

Indium (1at %) doped ZnO and ZnO nanoparticles have been synthesized via sol gel method. The structural characters of the synthesized nanoparticles have been studied by X-ray diffraction pattern (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). From synthesized nanopowders a tablet was prepared by using the isostatic pressing and then sintered at 600°C. Then, the gas-sensing properties of ZnO and IZO powder tablets were evaluated with respect to the acetone gas at different temperatures and concentrations. XRD pattern and SEM images showed the prepared samples were crystallized in the wurtzite structure with the average particle size of 32 and 27 nm. The gas sensing measurement results showed that the indium dopant ions improved the gas sensitivity of ZnO for high acetone concentrations effectively. Therefore, it is suggested that the IZO tablet can act as reliable and low cast gas sensor for acetone detection. Sintering temperature strongly increased the grain size and density of samples. EDX analysis confirmed the presence of indium in zinc oxide structure.