Logo der FH-Münster
Einrichtungs-Logo
Einrichtungs-Logo
DE

Photovoltaik: Lehrbuch zu Grundlagen, Technologie und Praxis | 5. Auflage erschienen

Das Standardlehrbuch zu Photovoltaik!

Dieses Lehrbuch liefert Antworten auf die wichtigsten Fragen zur Photovoltaik-Technik. Es werden grundlegende physikalische und elektrotechnische Fragestellungen behandelt.

K. Mertens: Photovoltaik - Lehrbuch zu Grundlagen, Technologie und Praxis, 5. Auflage (2020) --> Mehr

 

Laser-induced nanocrowns improve detection limits of Raman spectroscopy

Applications and physical formation mechanisms of metallic crown-like nano-patterns were studied in a collaborative research paper recently published together with the Far Eastern Federal University in Vladivostok, Russia, in Applied Surface Science. Metal nanocrowns appear upon nanosecond laser patterning of thin metal layers deposited on a glass or silicon substrates. They are formed due to Rayleigh-Plateau hydrodynamic instability in the molten metallic rim around the laser-induced crater. Such structures can be used to increase the detection sensitivity of Raman spectroscopy.

D.V. Pavlov, S.O. Gurbatov, S.I. Kudryashov, E.L. Gurevich, A.A. Kuchmizhak: Laser-induced surface relief nanocrowns as a manifestation of nanoscale Rayleigh-Plateau hydrodynamic instability, Appl. Surf. Sci. 511, 145463 (2020), doi: 10.1016/j.apsusc.2020.145463

Monitoring the corrosion of concrete structures with optical pH sensors

The carbonation of reinforced concrete leads to undesirable material damage by the corrosion of the steel beams due to the impact of CO2 and the associated drop in pH. A pH value below 11.5 indicates the occurrence of carbonation and consequential damage. Prof. Schäferling from the Laboratory for Photonic Materials has developed in cooperation with the Federal Institute for Materials Research and Testing (BAM) a fiber-optic sensor for non-destructive monitoring of the pH in concrete which is now studied in test specimens with regard to long-term functionality.

J. Bartelmess, D. Zimmek, M. Bartholmai, C. Strangfeld, M. Schäferling: Fibre optic ratiometric fluorescence pH sensor for monitoring corrosion in concrete, Analyst (2020), doi: 10.1039/C9AN02348H

Helpful electric fields

By careful adjustment of surface charges Jan-David Goossen succeeded to co-deposit two quite different nanomaterials as homogeneous porous layers. For this purpose he applied so-called electrophoretic deposition, which is well-known also in industrial coating technology. The nanocomposites of ZnS and carbon are promising for various applications in (photo-)electrocatalysis.

Jan-David Goossen, Amina Alizade, Michael Bredol: Electrophoretic deposition of carbon/ZnS composite electrode layers, Materials Chemistry and Physics 239 , 122083 (2020), doi: 10.1016/j.matchemphys.2019.122083

 

Innovation award for new laser processing method

A mixture of dust and air can explode. This hazard particularly occurs on filling and emptying of big bags with bulk materials when the used packaging foil becomes electrostatically charged. To avoid the risk of a dust explosion, the Laser Centre of FH Münster University of Applied Sciences and the company EMPAC have developed a new laser processing method. With this method, foils can be treated in a way that they are able to discharge electrical load. The new method is simpler, more efficient and more cost-effective than previously used methods.

The successful cooperation was now award with the "Innovationspreis Münsterland" and took the first place in the category 'Science meets Economy'.

Detailed press release (only available in German)

 

Crack-free crystals for optical spectroscopy

Single crystals are used in daily life as crystal oscillator in watches, as an active medium in lasers or as detector material in X-ray devices. Due to their homogeneous structure and high purity, single crystals are also very well suited for determining their material properties. Together with the industrial partner FEE (EOT), a process for the synthesis of large, crack-free KEu(WO4)2 single crystals has been successfully developed. These rose-red colored crystals provided the basis for the characterization of various optical and physical properties of KEu(WO4)2. It turned out that single-crystalline KEu(WO4)2 is a promising material, both for use as a red emitter in high-power LEDs and for use as a scintillator.

Patrick Pues, Sebastian Schwung, Daniel Rytz, Lea Schubert, Steffen Klenner, Frank Stegemann, Rainer Pöttgen, Thomas Jüstel: Temperature and time dependent photoluminescence of single crystalline KEu(WO4)2, J. Lumin. 215, 116653 (2019), doi: 10.1016/j.jlumin.2019.116653

 

UV emitting nanoparticles for medical applications

Praseodymium-doped LuPO4 emits UV-C radiation between 225 and 280 nm, where DNA shows strong absorption bands. Due to the low penetration-depth of UV-C in biological tissues, and the small size of the particles new treatment with cell-damaging UV-C radiation is possible. The goal is to achieve the best compromise between efficient UV emission upon X-ray excitation and small particle size. We propose the use of these particles as novel radiation sensitizers to the well-known radiation therapy, especially for the treatment of hypoxic tumor cells.

Sara Espinoza, Max-Fabian Volhard, Heike Kätker, Heike Jenneboer, Anne Uckelmann, Markus Haase, Matthias Müller, Martin Purschke, Thomas Jüstel: Deep Ultraviolet Emitting Scintillators for Biomedical Applications: The Hard Way of Downsizing LuPO4:Pr3+, Particle & Particle Systems Characterization, 1800282 (2018), doi: 10.1002/ppsc.201800282

Michael R. Squillante, Thomas Jüstel, R. Rox Anderson, Charles Brecher, Daniel Chartier, James F. Christian, Nicolas Cicchetti, Sara Espinoza, Daniel R. McAdams, Matthias Müller, Brooke Tornifoglio, Yimin Wang, Martin Purschke: Fabrication and characterization of UV-emitting nanoparticles as novel radiation sensitizers targeting hypoxic tumor cells, Optical Materials 80, 197-202 (2018), doi: 10.1016/j.optmat.2018.04.033

 

More power through colloid chemistry

From studies on luminescent nanocomposites the importance of precise control of their nanostructure is well known. Aleksandra Szydło now has shown, that such insight gained from optical materials can be transferred to a very different application of nanocomposites: low temperature fuel cells. Using methodology developed for the assembly of optical nanocomposites she prepared colloidal precursor systems for electrocatalytic layers leading to fuel cells with improved electrical performance.

Michael Bredol, Aleksandra Szydło, Ivan Radev, Wladimir Philippi, Roland Bartholomäus, Volker Peinecke, Angelika Heinzel: How the colloid chemistry of precursor electrocatalyst dispersions is related to the polymer electrolyte membrane fuel cell performance, Journal of Power Sources 402, 15-23 (2018), doi: 10.1016/j.jpowsour.2018.09.005

 

Lösungen für Unlösliches: Tone als Nanotransporter

Wasser-Unlöslichkeit von Substanzen ist eines der häufigsten Probleme des Chemiealltags - besonders lästig, wenn es sich um wertvolle Substanzen wie Farb- und Leuchtstoffe handelt, die sich in wässrigem Milieu sehr häufig zusammenlagern und dabei ihre Funktion verlieren. Besondere Bedeutung hat dies für Leuchtstoffe, die als Biomarker diagnostische Aufgaben übernehmen könnten, aber an der vorwiegend wässrigen Umgebung an und in Zellen scheitern. Die eher zufällige Beobachtung, dass Leuchtstoffe mittels sogenannter Nano-Schichtsilikate (Tone mit Abmessungen weniger Nanometer) auch in Wasser "funktionieren" hat uns zu einer ganzen Reihe von Untersuchungen stimuliert. Beispiele:

M. C. Staniford, M. M. Lezhnina, U. H. Kynast: Phthalocyanine blue in aqueous solutions, RSC Advances 5, 3974-3977 (2015) --> zum Aufsatz

T. Felbeck, S. Mundinger, M. M. Lezhnina, M. Staniford, U. Resch-Genger, U. H. Kynast: Multifold Fluorescence Enhancement in Nanoscopic Fluorophore-Clay Hybrids in Transparent Aqueous Media, Chemistry - A European Journal 21, 7582-7587 (2015) --> zum Aufsatz

 

Licht als Heilserum

MRSA ist (mit Recht) zu einem mit Schrecken behafteten Schlagwort geworden. Es steht für das Bakterium "Methicillin-resistenter Staphylococcus aureus" oder schlicht den "Krankenhauskeim" (zu Unrecht, denn der Zoo Antibiotika-resistenter Bakterien wächst). Um dem Dilemma zu begegnen, wird u. a. auch mit Licht gearbeitet, das in Kombination mit Photokatalysatoren sehr kurzzeitig und lokal eng begrenzt eine keim- und zelltötende Form des Sauerstoffs ("Singulettsauerstoff") erzeugen kann. In einer besonderen Kombination aus Ton-Abkömmlingen und einfachen, sogenannten Phthalocyaninen konnten wir erstmalig zeigen, dass mit geringem Aufwand u. a. MRSA zu mehr als 99 % abgetötet werden kann.

M.C. Staniford, M. M. Lezhnina, M. Gruener, L. Stegemann, R. Kuczius, V. Bleicher, C. A. Strassert, U. H. Kynast: Photophysical efficiency-boost of aqueous aluminium phthalocyanine by hybrid formation with nano-clays, Chem. Commun. 51 13534-13537 (2015) --> zum Aufsatz

M. Grüner, L. Tuchscherr, B. Löffler, D. Gonnissen, K. Riehemann, M. C. Staniford, U. Kynast, C. A. Strassert: Selective Inactivation of Resistant Gram-Positive Pathogens with a Light-Driven Hybrid Nanomaterial, ACS Applied Materials & Interfaces 7, 20965-20971 (2015) --> zum Aufsatz

 

A new concept for disk lasers

Industrial laser materials processing requires increasingly higher laser power to speed up processes and thus make them more efficient. If excellent beam properties are required, the maximum laser power of nearly all types of lasers is limited by the heat production in the active laser medium. We have developed and experimentally tested a new laser concept which allows investigation of the physical effects near this limit and possibly shifting of the limit. These investigations are published in the following papers:

C. Vorholt, U. Wittrock: Intra-cavity pumped thin-disk laser with 1.74% quantum defect, Optics Letters 40, 4819-4822 (2015) --> paper download (pdf)

C. Vorholt, U. Wittrock: Wavelength control by angle-tuning of the laser radiation in an intra-cavity pumped Yb:YAG thin-disk laser, Advanced Solid State Lasers (ASSL), Berlin (2015) --> paper download (pdf)

 

Um unsere Webseite für Sie optimal zu gestalten und fortlaufend verbessern zu können, verwenden wir Cookies. Weitere Informationen und die Möglichkeit zum Widerruf finden Sie in unserer Datenschutzerklärung.
Seite drucken