Dionigi, Fabio4; Nielsen, Morten Godtfred1; Pedersen, Thomas5; Hansen, Ole2; Chorkendorff, Ib1; Vesborg, Peter Christian Kjærgaard1
1 Department of Physics, Technical University of Denmark2 Experimental Surface and Nanomaterials Physics, Department of Physics, Technical University of Denmark3 Department of Micro- and Nanotechnology, Technical University of Denmark4 Silicon Microtechnology, Department of Micro- and Nanotechnology, Technical University of Denmark5 DTU Danchip, Technical University of Denmark
A new Pyrex-based μ-reactor for photocatalytic and optical characterization experiments is presented. The reactor chamber and gas channels are microfabricated in a thin poly-silicon coated Pyrex chip that is sealed with a Pyrex lid by anodic bonding. The device is transparent to light in the UV-vis-near infrared range of wavelengths (photon energies between ∼0.4 and ∼4.1 eV). The absorbance of a photocatalytic film obtained with a light transmission measurement during a photocatalytic reaction is presented as a proof of concept of a photocatalytic reactivity measurement combined with in situ optical characterization. Diffuse reflectance measurements of highly scattering photocatalytic nanopowders in a sealed Pyrex μ-reactor are also possible using an integrating sphere as shown in this work. These experiments prove that a photocatalyst can be characterized with optical techniques after a photocatalytic reaction without removing the material from the reactor. The catalyst deposited in the cylindrical reactor chamber can be illuminated from both top and bottom sides and an example of application of top and bottom illumination is presented.
Review of Scientific Instruments, 2013, Vol 84, Issue 10