Division Biophotonics ss currently seeking a Student (w/m/d) for a master thesis
Description
The unequivocal determination of quantum yield (QY) of luminescent materials is one of the most important measures of material quality. However, the commonly used relative procedures are not suited for liquid and solid scattering luminescent samples relevant, e.g., for material research focused on luminescent particles and phosphors but also in industry, for applications like LEDs and plasma displays.
The motivation and focus of this research project is to fill the gap and systematically assess different simple and reliable methods to measure the QY of different types of scattering and luminescent materials.
This will involve the thorough optical characterisation of various types of liquid and solid scattering samples and films containing, e.g., typical LED-converter materials like YAG:Cer, mainly using techniques for the determination of the absolute QY such as integrating sphere spectroscopy. Sample preparation will mainly focus on embedding LED-converter materials in thin polymer films.
In addition, dye solutions containing known amounts of differently scattering particles will be prepared and also, some samples will be provided by an industrial collaboration partner. Luminescence, absorption, and reflection measurements of these samples will be done to systematically examine the influence of sample parameters such as luminophore or converter material concentration or layer thickness of films on the resulting QY. Furthermore, the correlation between different material-specific properties will be investigated to bring forward other means to evaluate the QY of scattering, luminescent systems.
Qualifications
- Studies of physics or chemistry or physical chemistry or related subjects
- Experiences in optical spectroscopy are advantageous
- Interest in interdisciplinary work between physics and chemistry
Contact
Dr. Ute Resch-Genger
1.2 Biophotonics
Telephone: (030) 8104 5980; 0174-9302761
e-mail: ute.resch@bam.de
Dr. Saskia Fiedler
1.2 Biophotonics
Telephone: (030) 8104 5729
e-mail: saskia.fiedler@bam.de