Photocatalytic Selectivities of Ethane, Methane and Dimethylether Controlled by Reaction Conditions and TiO2 Structure in the Degradation of Acetic Acid

Abstract

The impact of photon flux, humidity and residence time using TiO 2 P25 and of the surface area of a series of CristalActiv PC TiO 2 anatase, on the selectivities of products formed in the continuous photocatalytic degradation of gaseous acetic acid (AA) on the scale of a few hundred ppm, in the presence or absence of O 2, was investigated. Under a continuous flow of air HCHO and C 2 H 6 were the most important products detected. CH 3 OH was also formed but to a lesser extent. Under a continuous flow of N 2 , the formation of these three products decreases whereas CH 3 OCH 3 , an interesting product which can be used as alternative fuel and CH 4 , is yielded. The impact of the experimental conditions on product formation, taking into account the intermediate formation of H 2 O 2 and the favorable impact of the surface area on the formation of CH 4 in the absence of oxygen and its opposite effect on the formation of C 2 H 6 in the presence of air, was discussed.The presence of rutile phase in TiO 2 P25 was also highlighted.

Efficient photoelectrochemical Kolbe C–C coupling at BiVO4 electrodes under visible light irradiation

“…Kolbe coupling has predominantly been investigated using TiO 2 and simple aliphatic acids but most commonly degradation of carboxylic acids occurs to a mixture of H 2 , CO 2 and alkanes depending on the reaction conditions. [69][70][71][72][73] Reported quantum efficiencies for Kolbe coupling are typically <1% due to electron hole recombination and byproduct formation. 71 Clearly PEC supports electron-hole separation and the fabrication of a porous semiconductor electrode allows more straightforward optimisation of light absorption and semiconductor-electrolyte interface and the double layer where photooxidation and radical dissociation occur.…”

The first report of deep eutectic solvent (DES) nano‐photocatalyst (n‐TiO2‐P25@TDI@DES (urea: ZnCl2)) and its application on selective oxidation of benzyl alcohols to benzaldehydes

“…Their high aspect ratio and coordination sites explain their enhanced catalytic activity 19–22 . In this regard, TiO 2 ‐P25 NPs have received a considerable deal of attention as both catalysts and supports because of their excellent features, such as non‐toxicity, enhanced activity, reusability, prolonged stability, safety and wide‐range antibiosis and photocatalytic behavior 23–26 . Degussa P25 is a mixture of rutile and anatase phases of TiO 2 (30:70) also known as a commercial TiO 2 ‐P25 27,28 .…”