Zeolites from fly ash embedded in a thin niobium oxide matrix for optical and sensing applications
Year: 2019
Type: conference-paper
Abstract: Thin films consisting of a sol-gel Nb 2 O 5 matrix doped with fly ash zeolites in different volume fractions were deposited by the method of spin-coating. Zeolites of Na-X phase were prepared by long-term alkaline atmospheric conversion of coal ash collected from the electrostatic precipitators in TPP "AES Galabovo" supplied by lignite coal from the "Maritza East" basin using two different molarities of alkaline activator (NaOH). The surface morphology and structure of zeolite powders and films were studied by scanning electron microscopy and X-ray diffraction, respectively. Optical constants (refractive index and extinction coefficient) along with thickness of the films were calculated using a previously developed procedure comprising two steps of nonlinear minimization of the discrepancies between the measured and calculated reflectance spectra of films deposited on silicon substrates. The liquid adsorption and vapor sensing ability of fly ash zeolites were tested by measuring the reflectance spectra of the films prior to and after exposure to probe acetone molecules. The application of zeolites from fly ash for optical sensing is demonstrated and discussed.
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: diamond
Funder: Bulgarian National Science Fund
Award: G817634839
OpenAlex ID: W2932909421