Correction of experimental action spectra for TiO2 photocatalysts measured using single-peak LEDs

Abstract

In this paper, we show the action spectra for five commercially available TiO2 photocatalysts and a uranyl-modified TiO2 photocatalyst prepared in laboratory. The action spectra are evaluated as spectral dependencies of photonic efficiency in the complete oxidation of acetone vapor under radiations from UV to visible range (367–734 nm) provided by seventeen single-peak light-emitting diodes (LEDs) making an assumption of pseudo-monochromatic type of radiation from these LEDs. A difference between action and absorption spectra of studied photocatalysts is considered and discussed. Based on the actual spectral irradiance of certain LED, a correction of experimental action spectra is proposed to improve their quality and reliability. The data illustrate a noticeable difference between actual and experimental action spectra obtained using pseudo-monochromatic single-peak LEDs. The conclusion about correct endpoint for the activation region of studied photocatalysts is made.