PhD; impact of solution processing on optoelectronic properties of TADF emitters

Department(s)

Applied Physics and Science Education

Reference number

V34.5724

Are you eager to work as an experimental photophysicist on unraveling the mechanisms that limit the efficiency of displays and other applications of organic light-emitting diodes (OLEDs)? In this PhD project, you will experimentally study the interaction of the excited organic molecules in OLEDs with charges and with other excited molecules. The focus will be on emitter molecules that utilize the principle of “thermally-activated delayed fluorescence”, and on materials that are used in OLEDs that can be fabricated using solution processing. Your work will show how this fabrication method can affect the efficiency loss processes in OLEDs, by making a comparison with materials that are fabricated using more conventional vacuum-deposition, and by using advanced simulations methods that are available in our group.

The project
Your project is part of an EU-funded Marie-Skłodowska-Curie Doctoral Network project called “TADFsolutions”, in which 12 PhD students  (“Doctoral Fellows”, DFs) will collaborate. 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.

The 12 PhD scientists will undertake multidisciplinary research to meet this design challenge. 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 also 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.

The experimental project at TU/e will be carried out under the supervision of prof.dr. Reinder Coehoorn in the Molecular Materials and Nanosystems group. The group has an extensive experimental infrastructure for film and device fabrication and for electrical and photophysical experiments, including for example time-resolved photoluminescence studies and studies that probe the electronic structure such as ultraviolet photoelectron spectroscopy (UPS). The group has also vast experience on the development and application of Monte Carlo simulations.

Applicants for the 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 the Netherlands for more than 12 months in the 3 years immediately prior to the recruitment.

• A master’s degree in physics or physical chemistry.
• Affinity with organic electronics and photophysical experiments.
• A research-oriented attitude.
• An application-oriented attitude.
• Ability to work in a team and interested in collaborating with academic and industrial
• partners.
• Perfect social and communicative skills.
• Fluent in spoken and written English.

• A meaningful job in a dynamic and ambitious university with the possibility to present your work at international conferences.
• A full-time employment for four years, with an intermediate evaluation (go/no-go) after nine months.
• To develop your teaching skills, you will spend 10% of your employment on teaching tasks.
• To support you during your PhD and to prepare you for the rest of your career, you will make a Training and Supervision plan and you will have free access to a personal development program for PhD students (PROOF program ).
• A gross monthly salary of € 2541,- in year one, building up to € 3247,- in year four and benefits (such as a pension scheme, pregnancy and maternity leave, partially paid parental leave) in accordance with the Collective Labor Agreement for Dutch Universities.
• Additionally, an annual holiday allowance of 8% of the yearly salary, plus a year-end allowance of 8.3% of the annual salary.
• Should you come from abroad and comply with certain conditions, you can make use of the so-called ‘30% facility’, which permits you not to pay tax on 30% of your salary.
• A broad package of fringe benefits, including an excellent technical infrastructure, moving expenses, and savings schemes.
• Family-friendly initiatives are in place, such as an international spouse program, and excellent on-campus children day care and sports facilities.

More information

Do you recognize yourself in this profile and would you like to know more? Please contact
prof. dr. Reinder Coehoorn, r.coehoorn[at]tue.nl.

For information about terms of employment, click here or contact HRServices.Flux[at]tue.nl

Please visit www.tue.nl/jobs to find out more about working at TU/e!

Application

We invite you to submit a complete application by using the 'apply now'-button on this page.

The application should include a:

• Cover letter in which you describe your motivation and qualifications for the position.
• Curriculum vitae, including a list of your publications and the contact information of
  three references.
• Brief description of your MSc thesis.

We look forward to your application and will screen it as soon as we have received it.
Screening will continue until the position has been filled.

Please keep in mind that you can upload only 5 documents up to 2 MB each.

If necessary please combine files.