The position advertised here looks at optimizing and tuning the optical characteristics of solution processed TADF OLEDs. Solution processed organic films are characterized by intrinsic disorder and inhomogeneity on different length scales. The PhD student will investigate how these inhomogeneities affect the optical characteristics of TADF OLEDs. New optical designs will be tested that to mitigate detrimental effects of inhomogeneity while still offering efficient emission and well-saturated colour. Specifically, the PhD student will focus on two aspects: (i) Develop and use Fourier plane angle-resolved photoluminescence mapping to monitor variations in molecular orientation in solution processed TADF OLEDs with high spatial resolution. (ii) Introduce and optimize microcavity device architectures to improve colour saturation compared to conventional TADF OLEDs whilst retaining robustness against any local film inhomogeneities introduced by the solution-based deposition of the organic materials.
This PhD is funded through the Marie-Skłodowska-Curie Doctoral Network TADFsolutions within the Horizon 2021 Programme of the European Commission. This advert is for a position in Germany, at the University of Cologne, to work with Prof. Malte Gather at the Humboldt Centre for Nano- and Biophotonics.
TADFsolutions will train a cohort of dynamic researchers to devise, develop and implement sustainable solutions for improving the device performance of solution-processed OLEDs for display applications. In the 21st century, displays play a central role. They are embedded in almost every type of electronic device and it is difficult to imagine a world without mobile phones, monitors and televisions. The pervasiveness of displays is driven by the disruptive organic light-emitting diode (OLED) technology. There are, however, some structural weaknesses in state-of-the-art vacuum-deposited OLEDs. These include the use of scarce metals within the materials of the device and the reliance on energy-intensive and expensive vacuum deposition fabrication methods. Solutions are required to make these devices more sustainable from the choice of materials to manufacturing processes.
Despite being cheaper, the current best solution-processed OLEDs (SP-OLEDs) still rely on scarce noble-metal based phosphorescent emitters and underperform compared to vacuum-deposited OLEDs. Starting from bespoke organic thermally activated delayed fluorescence emitter materials, the performance of SP-OLEDs will be maximized based on improved predictive models of charge transport, film processing techniques, and device structures. A strongly interconnected approach is required not only to effectively train the doctoral fellows but to meet the objectives. The TADFsolutions network consists of 8 leading European academics, 3 companies and 5 international partners that are equipped and experienced to not only confront the materials and device design challenges but to provide a robust multidisciplinary and intersectoral training environment to ensure that the DFs have the requisite skills, both soft and technical, to enter the employment market and contribute to securing Europe’s leading role in OLED materials.
This highly interlinked program gives a fantastic opportunity for the brightest young chemists, spectroscopists, theoreticians and device physicists to work together and learn complimentary skills that will be in high demand from European OLED industries. Leading experts will give courses on core scientific skills along with soft skills and international secondments will be offered, all to properly prepare them for their future careers. They will be part of a network answering a real industrial need and help to secure the future of our European OLED industries in the global OLED materials arena.
The TADFsolutions network comprises universities and companies in Germany, UK, France, Spain, The Netherlands and Switzerland. The positions include interdisciplinary training, internships in European and Non-European countries, summer schools and yearly international meetings.
Requirements: M.Sc. in Physics or Chemistry or equivalent degree. Proof of English proficiency as communication and teaching language throughout TADFlife is English (e.g. TOEFL or similar test, not for native speakers).
Applicants for this PhD position must not yet have been awarded a PhD degree and must be in the first 4 years (full-time equivalent) of their research careers prior to the recruitment. All applicants must not have resided or carried out their main activity (work, studies, etc.) in Germany for more than 12 months in the 3 years immediately prior to the recruitment.
Start date (planned): 1st October 2022 – 28th February 2023
Application deadline: 30th June 2022
Monthly Salary*: 3342€ + 600€ Mobility allowance + 660€ Family allowance.
* All monthly salaries listed are approximate gross amounts, including employer costs of employee according to MSCA ITN rules.