Waste Carbon-Derived Lanthanum Ferrite-Based Photocatalysts for 2-Propanol and Acetaldehyde Degradation

Abstract

Perovskite oxides have demonstrated great potential in catalysis and photocatalysis due to their unique morphological properties such as specific surface area and shape of particles. The current study focuses on the fabrication, characterization, and photocatalytic activity of LaFeO3 perovskite oxides (LF) prepared by solution combustion synthesis in the presence or in the absence of waste activated carbon (WAC). The materials were characterized for their structural, microstructural, textural and morphological properties, and their photocatalytic activity was tested in gas-solid regime using simulated solar and UV irradiation sources. Two model molecules, 2-propanol and acetaldehyde, were selected, and it was found that 2-propanol was strongly adsorbed on the material, while acetaldehyde showed a more modest adsorption in dark conditions. The photocatalytic results indicate that the activity depends both on the presence of WAC and on the type of irradiation used. The uncalcined nanocomposite powder (LF-WAC-NC), where WAC was mostly preserved, showed the best ability to degrade acetaldehyde under UV and even under solar irradiation, suggesting that the photocatalyst takes advantage of the wider range of energies provided by the broader solar light spectrum compared with the monochromatic LED. On the contrary, the calcined nanocomposite (LF-WAC-700) was less active probably due to the absence of carbon and the contemporary presence of high percentage of aluminosilicates that remain after the removal of carbon due to the heat treatment.