Abstract
This work aimed to study the annealing effects on the TiO2/SiO2 (Ti-O-Si) nanocomposite structural and optical properties and on its performances as a heavy metals detector. For this, we have prepared a 30% silica-70% titania mixture using a solid-solid reaction. Four samples (1,2,3,4) were prepared and annealed at 250 degrees C, 300 degrees C, 500 degrees C and 700 degrees C, respectively. We observed that crystalline fraction and average grain size increase as long as the annealing temperature does. Lead ion detection performances of composites samples were examined by mean of electrochemical impedance spectroscopy. We observed, for all samples, that R-ct was linear with the concentration of detecting Pb2+. Detection range was from 10(-7) to 10(-2) M not exceeding 5.10(-8) M. The electrode achieved desirable lead's sensing ability with high sensitivity.