Abstract
Invited this month′s cover picture are the groups of Professor Michael Mehring and Professor Marc Armbrüster at Chemnitz University of Technology. The cover pictures shows a graffiti displaying a distinctive part of the city center of the town. The artwork is oversprayed with the letters “TUC” (Technische Universität Chemnitz) using an bismuth oxido cluster from solution to obtain a yellow semiconductor coating of bismuth oxide, used to degrade the medicinal drug ethinyl estradiol under visible light irradiation. Read the full text of their Full Paper at https://doi.org/10.1002/open.201900323.
A spray‐coated bismuth oxide film (yellow) on a graffiti wall representing the functionalization of surfaces with photocatalytically active coatings Find out more about the story behind the front cover research at https://doi.org/10.1002/open.201900323.
1. What was the inspiration for this cover design?
The idea behind the design was inspired by our use of a spray coating technique to prepare coatings on various substrates. The intensively colored, visible light‐active α‐ and β‐Bi2O3 films complements the street artwork to give a symbiosis of art and natural science. The cover was designed by Susann Hofmann and Max Hofmann with the kind permission of the Tiefbauamt (City of Chemnitz) to use the self‐made photo of a graffiti, which you can see in the background of the cover picture.
2. What prompted you to investigate this topic/problem?
The removal of harmful organic compounds in wastewater still represents one of the greatest concerns in the context of limited access to drinking water worldwide. In combination with the use of a regenerative energy source like visible light, the development of a process, which starts from a molecule and ends up with a functional, photocatalytically active material, is one of the focal points of our research. It is also important to note, that research on photocatalyst particles in suspension is widespread, but their implementation into sewage treatment plants is hampered by cost‐intensive separation from the purified water. Therefore, we focus on non‐toxic immobilized semiconductors in scalable procedures. With regard to this, the “green” element bismuth is an interesting ingredient in novel functional materials.
3. What are the main challenges in the broad area of your research?
First of all, it is the development of efficient semiconductor materials, which should provide a suitable width of the band gap enabling visible light‐activity as well as suitable levels of the valence and conduction bands for the mineralization of organic pollutants. In addition, the design and immobilization of catalysts, which should be stable against photocorrosion and environmentally benign, is crucial. However, a major challenge is still the development of strategies to compare the photocatalytic efficiencies of materials and systems due to the use of various experimental setups in the scientific community.
M. Hofmann, L. Rößner, M. Armbrüster, M. Mehring, ChemistryOpen 2020, 9, 271.