PhD - Genk | More than two weeks ago
Towards The Artificial Tree by combining of the imec-expertise in the domain of Photovoltaics, Electrochemistry and Micro-fluidics
Currently, over 80% of the world’s primary energy supply is provided by fossil fuels carbon sources (coal, oil, gas). When we burn fossil fuels, we liberate the solar energy stored millions of years earlier in chemical bonds, but we are also generating CO2 as waste. Over the last few decades, it has become clear that the CO2 that is released in this way is affecting the climate stability of the biosphere. This requires to drastically change the way we produce and consume energy to rapidly decrease the amount of CO2 being release in the atmosphere. The sun gives us an opportunity to complete this energy revolution as it delivers the same energy to the Earth in about one hour as we currently use from fossil fuels, nuclear power and all renewable energy sources combined in a year.
Together with the generation of Green Electricity, one faces the challenge of storage. One of the possibilities for energy storage is the storage under the form of chemical energy. Power-to-Molecules describes the process to convert Electricity into chemical energy using sunlight, water and CO2. When generated from sunlight, this process product is often called solar fuels. Solar fuels could in principle be produced everywhere because the reactants are ubiquitous, but often dilute. If the CO2 can be captured directly from air a circular CO2 economy becomes a feasible possibility.
In imec, we are developing an integrated photovoltaic-electrochemical (PV-EC) system consisting of a multi-junction solar cell/module operating under 1-sun conditions and an electro-chemical cell to produce chemical products such as hydrogen, methanol or ethanol directly from water, CO2 and sunlight. The multijunction cell would be based on the combination of a low-bandgap subcell based on crystalline Si or a material with similar bandgap like CIGS in combination with a perovskite topcell.
This Ph.D-project focuses on the practical realization of such an integrated PV-EC device at module level with maximal avoidance of the use of intermediate voltage conversion stages. This means the voltage of the cell or series connection of cells will be applied preferably without intermediate stage to the electrochemical part. The student has to address the problem of bringing the voltage and power of the cell to the electrolyser cell whilst minimizing resistive losses and avoiding physical contact between the surfaces of the cell and the corrosive environment of the electrolyser cell. This will require novel solutions on the level of PV-cell and module architectures with feedthrough vias from the PV-cell to the electrolyser cell. This also addresses issues of encapsulation to avoid degradation of the active cell. Concurrently, the student has also to propose and test solutions for the supply and evacuation of the reagentia and reaction products using micro-fluidic concepts. The work will also comprise the evaluation of the Power-to-Molecule conversion efficiency and the dynamic characteristics of the integrated device.
From the candidate, a strong interest in semiconductor physics, semiconductor technology, electrochemical processes and fluid dynamics is required as well as the capacity to oversee the integration aspects. The Ph.D will work in one of the world’s leading semi-conductor research centers in a group of scientists, engineers and technicians supporting this thesis.
Required background: Master of Science, Master of Engineering
Type of work: 15% literature study + 15% design + 50% process development/process integration + 20% characterization
Supervisor: Jef Poortmans
Co-supervisor: Philippe Vereecken
Daily advisor: Joachim John
The reference code for this position is 2021-134. Mention this reference code on your application form.