Master Project: Controlled Solvent Vapor Annealing for Determining Interactions in Multicomponent Systems
Job offer from February 26, 2018
Thin films of conducting polymers or small molecules provide the core function of organic electronics devices, such as organic solar cells, light-emitting diodes and transistors. This “active layer” usually consists of two or more solid components which are cast from a common solvent. During solvent evaporation the blend may phase separate, whereby the electronic performance of the final thin-film device strongly depends on the phase separated micromorphology. Predicting phase behavior and micromorphology requires information on solute-solute and solute-solvent interaction. The latter can be determined by rate of swelling measurements of polymer films upon controlled exposure to solvent vapor. New ideas exist to use this known technique in an indirect way to i) determine solvent-solute interaction on materials that would not/hardly swell in the pure state and ii) determine solute-solute interaction.
Project and activities
Our group has recently built up a set-up that combines controlled solvent vapor exposure with white light reflectometry for accurate thickness measurement. The set-up is new and needs to be tested and optimized towards reliable usage in determining molecular interactions in rate-of-swelling experiments. The foreseen master project consists of three parts: i) testing and calibrating the set-up on single polymer films by applying various solvent-solute combinations, ii) improving the set-up to reach optimal flexibility and accuracy, iii) performing rate of swelling experiments on blend films based on combinations of polymers and small molecules and extracting quantitative information on monomeric interaction using models based on polymer- and statistical thermodynamics.
What are we looking for?
For carrying out this project we are looking for a motivated master student in the field of physics, physical chemistry, materials science or engineering. The ideal student has excellent grades and seriously considers embarking on a PhD project after finishing his/her undergraduate study. Computer programming skills and the motivation to work at the interface between experimentation and theory are a must. The duration of the project is foreseen to be six months.
Please direct questions and applications to:
Dr. Jasper J. Michels (Group Leader)
Department for Molecular Electronics
Max Planck Institute for Polymer Research
Tel: +49 (0)6131 379 607