Currently, over 80% of the world's primary energy supply is provided by fossil fuels carbon sources (coal, oil, gas). For the last two centuries fossil fuels, generated from biomass over millions of years, have been extensively used in anthropic activities. 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. Therefore, there is a need for an energy transition from fossil fuels to non- fossil-based energies. This transition has already started and must be completed during the present century. 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. Sunlight is a dilute form of energy, it needs to be converted into other forms of energy in order to be used in a profitable way, such as heat, electricity, or fuels.
Solar to chemicals describes the process to convert solar energy in chemical energy using sunlight, water and CO2. In literature this process product is often called chemicals, material or solar fuels. Solar fuels could in principle produced everywhere because the reactants are ubiquitous. If the CO2 can be captured directly from air a circular CO2 economy is possible. Although nearly any energy source can be used to drive chemical reactions, sunlight is rarely used for this purpose directly up to now.
The primary feedstocks for this solar enhanced chemical process are water (H2O), nitrogen (N2) and carbon dioxide (CO2). The main products would be molecular hydrogen (H2) obtained through water splitting and a series of carbon-based chemical compounds, obtained through the simultaneous reduction of CO2 large scale. The produced solar fuels and commodities (basic feedstock used in the chemical industry) could be stored, transported and used within existing assets, replacing oil and its refined products.
In industrial application now, large electrolysers based on alkaline electrolyte water splitting are in production for H2. For catalytic CO2 reduction no industrial solution is available today.
In imec, we are developing an integrated system consisting of a multi-junction solar cell and an electro-chemical reactor to produce chemical products such as methanol or ethanol directly from water, CO2 and sunlight.
This PhD thesis project focuses on the system-level modelling of such an integrated device in order to provide the optimized parameters to reach the highest solar to fuel efficiency. The research project builds upon in-house expertise of modelling the individual system components in COMSOL, PV Lighthouse and IMEC's photovoltaic energy yield modelling framework.
From the candidate, a strong interest in deepening her/his own theoretical and modelling background in semiconductor physics, electrochemical processes and fluid dynamics is required. The PhD student will work in one of the world's leading semi-conductor research centers in a group of scientists, engineers and technicians supporting this thesis.
- Master of Science or Master of Engineering
- Very good English language skills
- Strong empathy for theory, modelling and characterization
Type of work: 15% literature study + 60% modeling + 25% characterization
Supervisor: Jef Poortmans
Daily advisor: Joachim John, Imre T Horvath
The reference code for this position is 2020-067. Mention this reference code on your application form.
Chinese nationals who wish to apply for the CSC scholarship, should use the following code when applying for this topic: CSC2020-29.