article posted 1 April 2016
Gundula Helsch studied chemistry at Clausthal University of Technology before work on a PhD on the origin of the aging process of porous sol-gel antireflection coatings. She has subsequently worked as a research assistant, with Professor Frischat, at the Institute of Non-Metallic Materials and is currently head of the sol-gel group working for Professor Deubener.
Antireflective coatings with photocatalytic activity
Gundula Helsch* & Joachim Deubener
Clausthal University of Technology, Insitute of Non-Metallic Materials, Zehntnerstrasse 2a, 38678 Clausthal-Zellerfeld, Germany
The solar transmittance of solar cover glasses can be increased by antireflective coatings. While a high solar transmittance is essential for a high efficient solar collector, volatile organic contaminations from the atmosphere as well as biofouling processes on the cover glasses will reduce the transmitted solar radiation. By modifying the AR-coating with photocatalytic active oxides the organic contaminations will be decomposed by photo-induced oxidation. Depending on refractive index and band gap of the metal oxide used, transmittance in general and UV-transmittance are reduced respectively. Besides the investigation of the samples by secondary neutral mass spectrometry (SNMS), XRD and UV-VIS-spectroscopy, the photocatalytic activity under UV-A radiation as well as in the visible light was proved by stearic acid degradation.