Ethanol Photoelectrooxidation on TaON-Based Photocatalysts: Products Distribution Analyses by HPLC and DEMS On-line

Photoelectrochemical cells (PECs) have attracted extensive attention because of their capacity to convert light into electric power or chemical fuels. In these systems, the photocatalysts efficiency is associated to the generation of electron/hole pairs (e- /h+) caused by irradiation on the semiconductor surface by light (hѵ≥Eg). Photocatalysts that function efficiently under visible light are essential for the use on solar energy conversion and, in this context, tantalum oxynitride has been considered as an interesting material [1]. Here, the photocatalysts were formed by Pd- and/or IrO2-loaded TaON prepared from Ta2O5 by heating under NH3 flow at 850oC [2]. CVs curves (Fig. 1a) show the TaON-based materials performance for the ethanol oxidation reaction (EOR). Pure TaON did not present activity, as can be observed (black line). However, IrO2/Pd/TaON was able to photo-electro-oxidize ethanol, producing acetic acid and crotonaldehyde as final products (Fig. 1b), among other species.