Photocatalytic oxidation of CO on TiO₂ in microreactors

Contacts:

Peter Vesborg, CINF, DTU Physics, 4525-3113 (peter.vesborg@fysik.dtu.dk)

Jakob Olsen, CINF, DTU Physics, 4525-3254 (jakob.olsen@fysik.dtu.dk)

Ib Chorkendorff, CINF, DTU Physics, 4525-3170 (ibchork@fysik.dtu.dk)

Picture of a 1,6 x 2 cm microreactor in the process of being sealed before use, the circular chamber is where the catalyst is deposited and the reaction takes place. The graph shows how CO2 is produced from CO and O2 when the light is turned on.

Photocatalysis is the acceleration of a light activated chemical reaction using a catalyst to absorb the light. A topic in photocatalysis that has seen a growing interest in recent years is photocatalytic oxidation treatment of polluted water and air as a viable cleanup process. The most commonly catalyst material used today is TiO₂, which is a very active photocatalyst, but has the disadvantage of only being able to utilize light with wavelengths below 400 nm, which is only a small part of sunlight.

Using microreactors to test the photocatalytic activity of different materials is a unique way of measuring the direct results of the reaction as it happens. It is also a reasonable fast method, allowing screening of different materials to find better candidates for photocatalys, either by improving the reactivity, or by increasing the light spectrum which can be utilized.

The project is experimental, and your primary focus will be on investigating the effect of modifying TiO₂ - using for example platinum nanoparticlesparticles - with respect to photocatalytic activity. This includes synthesizing the catalyst, assembling the microreactors, and performing the photocatalytic reactivity measurements.