Would you enjoy becoming an expert in the fundamental physics processes of luminescence materials and enable electricity generating windows? Contact us today!

Job description

You will combine your creativity with analytical- and experimental skills to discover new electricity generating luminescent window coatings. You will publish new fundamental solid state physics and optics processes and explore options for scale-up of your new coatings with a start-up and the glass industry. More info on the topics of the research group can be found at www.vanderkolklab.com
In this Ph D project you will develop luminescent materials for building integrated photovoltaic (BIPV) technology. You will make and study new types of strongly absorbing luminescent solar absorber materials of just a few hundred nm thick, that can convert the UV+VIS part of the solar spectrum into infra-red luminescence. When applied as a coating to windows, these materials can enable a cost-effective electricity generating PV-window following the principle of a Luminescent Solar Concentrator (LSC). A LSC can harvest sunlight by absorbing, re-emitting, and subsequently guiding light, like in an optical fibre, to solar cells integrated in the windowpane that convert the light in electric power.
To successfully develop new valuable luminescent absorber materials, it is crucial you will get fundamental understanding of the physical processes underlying the luminescence mechanism of the materials. One of the scientific challenges is to understand how generated electron-hole pairs can transfer their energy to the luminescence centres. The strongest possible absorptions in an inorganic material are so-called bandgap absorptions in which an electron is excited from the valence band (VB) to the conduction band (CB) leaving behind a hole in the VB. Although there are many materials (hosts) with a small bandgap that absorb the entire visible part of the solar spectrum (black materials), very few show efficient luminescence of doping ions. Host-to-doping ion energy transfer is often described by a resonant process between (self-trapped) exciton emission and doping ion absorption. The materials of this project have a smaller bandgap and are selected to have a small exciton binding energy causing transfer involving excitons to be inefficient. In the new materials, sequential transfer of first the electron followed by the hole is the anticipated transfer process to the luminescence centres.
The fundamental insights are obtained first by time and temperature resolved optical and luminescence spectroscopy combined with a variety of techniques to analyse the structure, (defect) composition and morphology of the films. Secondly fundamental understanding involves data interpretation and model development using knowledge of solid-state physics, optics and quantum mechanics. Ideally the obtained insights will be used to select other materials with improved properties during your project.
In this project you will learn the ins and outs of reactive DC, RF and pulsed magnetron sputtering, the working horse technology in glass coating industry, to make the luminescence materials. Targeted materials are rare earth (like Yb) and transition metal (like Mn) doped inorganic semiconducting materials, emitting in the infra-red spectral range, where silicon solar cells have high conversion efficiency.
The Luminescence Materials group at Delft University of Technology has more than 30 years of experience with luminescent materials research and collaborates with a start-up company and glass coating industry to facilitate a route to large scale application of the coatings as windows. You will be working in a team, headed by your promotor, with other Ph D's, technicians, a start-up company and glass coating industry. A Ph D student receives a general education by the University Graduate School and can be involved in activities like teaching practicals for a small part of your time and co-supervise graduation project at the bachelor and master level.

Requirements

You enjoy solving complex challenges related to for example solid state physics and optics.
After a well defined start of your Ph D project with pre-selected materials and methods we expect you to take the lead in your project more and more to solve unexpected problems and use your growing knowledge, experience and creativity to discover new exciting materials. We strive to actively support your professional growth and project skills to enable you to utilise your full potential.
Please show in your motivation letter and CV that you have

• a university master in physics or a master specialised in inorganic (physical) chemistry.
• strong analytical skills to develop models describing luminescence mechanisms and fit models to experimental data.
• a proven interest in, and experience with, experimental (materials) research.

It is beneficial but not mandatory to have experience with any of the topics mentioned in the job description.
Doing a Ph D at TU Delft requires English proficiency at a certain level to ensure that the candidate is able to communicate and interact well, participate in English-taught Doctoral Education courses, and write scientific articles and a final thesis. For more details please check the Graduate Schools Admission Requirements.

Schematic illustration, not to scale, of the hole trapping process in Cu Ga(O,S,Se,Te)2. After electron trapping by Yb3+, the hole trapped at the coordinating ligands forms a charge transfer state with energy slightly lower than the top of the VB as indicated by the up-side-down parabola’s following the “hole-picture” model. From the CT-state, the hole can be trapped by Yb2+ leaving Yb3+ in the excited state.

Conditions of employment

Doctoral candidates will be offered a 4-year period of employment in principle, but in the form of 2 employment contracts. An initial 1,5 year contract with an official go/no go progress assessment within 15 months. Followed by an additional contract for the remaining 2,5 years assuming everything goes well and performance requirements are met.
Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities, increasing from € 2770 per month in the first year to € 3539 in the fourth year. As a Ph D candidate you will be enrolled in the TU Delft Graduate School. The TU Delft Graduate School provides an inspiring research environment with an excellent team of supervisors, academic staff and a mentor. The Doctoral Education Programme is aimed at developing your transferable, discipline-related and research skills.
From 1 September next, a salary increase of 3.7% applies due to a Collective Agreement amendment, followed by an additional 1% increase on 1 January 2025. In addition, most employees employed on 1 September 2024 will receive a one-off payment of €300 gross based on full-time employment.
The TU Delft offers a customisable compensation package, discounts on health insurance, and a monthly work costs contribution. Flexible work schedules can be arranged.
For international applicants, TU Delft has the Coming to Delft Service. This service provides information for new international employees to help you prepare the relocation and to settle in the Netherlands. The Coming to Delft Service offers a Dual Career Programme for partners and they organise events to expand your (social) network.

TU Delft (Delft University of Technology)

Delft University of Technology is built on strong foundations. As creators of the world-famous Dutch waterworks and pioneers in biotech, TU Delft is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society. For generations, our engineers have proven to be entrepreneurial problem-solvers, both in business and in a social context.
At TU Delft we embrace diversity as one of our core values and we actively engage to be a university where you feel at home and can flourish. We value different perspectives and qualities. We believe this makes our work more innovative, the TU Delft community more vibrant and the world more just. Together, we imagine, invent and create solutions using technology to have a positive impact on a global scale. That is why we invite you to apply. Your application will receive fair consideration.
Challenge. Change. Impact!

Faculty Applied Sciences

With more than 1,100 employees, including 150 pioneering principal investigators, as well as a population of about 3,600 passionate students, the Faculty of Applied Sciences is an inspiring scientific ecosystem. Focusing on key enabling technologies, such as quantum- and nanotechnology, photonics, biotechnology, synthetic biology and materials for energy storage and conversion, our faculty aims to provide solutions to important problems of the 21st century. To that end, we educate innovative students in broad Bachelor's and specialist Master's programmes with a strong research component. Our scientists conduct ground-breaking fundamental and applied research in the fields of Life and Health Science & Technology, Nanoscience, Chemical Engineering, Radiation Science & Technology, and Engineering Physics. We are also training the next generation of high school teachers.
Click here to go to the website of the Faculty of Applied Sciences.

Additional information

For more information about this vacancy, please feel free to contact:
Erik van der Kolk, E.vander Kolk@tudelft.nl. If you fit the requirements and would prefer an informal chat or lab visit before applying, you are welcome to contact Erik before September 25 to schedule an appointment. A motivation in not required in this case however we do ask you to share your Linked In or CV.

Application procedure

Are you interested in this vacancy? Please address your application to Erik van der Kolk and apply no later than 26 September 2024 via the application button and upload:

• CV
• Motivation letter describing your analytical and/or modelling skills, and experience with experimental research
• Your master thesis report
• Your bachelor and master gradelist
  
  Please note:
  
• A pre-employment screening can be part of the selection procedure.
• Applying for an exemption for specific research and educational areas is an obligatory part of the selection procedure for this vacancy. This exemption must be obtained from the Ministry of Education, Culture and Science (OCW) before an employment contract is agreed upon. Click here for more information.
• You can apply online. We will not process applications sent by email and/or post.
• Please do not contact us for unsolicited services.