PhD scholarship in Improvement of Cell Strength in High Temperature Electrolysis Cells

The section for Mixed Conductors, Department of Energy Conversion and Storage, Technical University of Denmark, is seeking a candidate for a PhD student position as part of the project “Synfuel: Sustainable synthetic fuels from biomass gasification and electrolysis”.

Electrolysis of water will become a key technology in the future energy system to balance increasing amounts of renewable energy against the demand and to provide sustainable fuels to the transport sector. When renewable electricity production exceeds the demand, the surplus can be used for production of hydrogen via steam electrolysis for instance in a Solid Oxide Electrolysis Cell (SOEC). This hydrogen can advantageously be added to “producer gas” obtained by thermal gasification of biomass to create a synthesis gas, which can be further catalytically upgraded to transport fuels like e.g. methanol. There are several synergies between the high temperature electrolysis process and the gasification process resulting in a high overall efficiency of the combined biomass-gasifier+SOEC – plant (e.g. surplus heat from the gasifier can be used to improve electrolysis efficiency and the oxygen also produced in the water splitting can be used in the gasifier).

Both biomass gasification and electrolysis by SOEC can become key technologies in a future sustainable energy system. Current challenges are to bring the technologies up in scale and to improve them with respect to key performance characteristics; an important one for the case of SOEC is to make the cells both tougher and stronger. At the heart of this lies improving the understanding how mechanical failure progresses in porous ceramics.

Project aims 
The project aim is on the technological level to prepare tougher solid oxide cells which can facilitate up-scale in size, and on the more fundamental level to elucidate what limits the mechanical reliability of the solid oxide cells. The mechanical support of the state of the art cells is based on yttria stabilized zirconia. This is a very important functional/structural ceramic, which due to its unique mechanical and chemical properties finds use not only in electro-ceramics (lambda sensors, SOEC) but also as thermal barrier coatings, for dental and structural applications (ceramic knives). Due to these important applications the material has been intensively studied, however, effects of e.g. porosity on the failure modes as well as effects of high temperature on the toughening mechanism in the compound are very poorly understood. It is the aim of the project to investigate these.

Job description 
You will be part of the section for Mixed Conductors at DTU Energy, but will also interact with other sections of the Department and with external partners of the project. In particular, a close cooperation with INSA in France is planned. The PhD position has a multidisciplinary nature and thus you will need to draw on the knowledge of several experts to reach the project aims. You will be engaged in preparation of tailored zirconia microstructures suitable for investigating propagation of mechanical failures. Also effects of material composition will be investigated. Besides preparing samples with a desired microstructure the mechanical properties of the samples will be investigated for example by DCB (“double cantilever beam”) and 4-point bending experiments. For the latter you will use a recently constructed unique setup allowing strength investigation at high temperature in controlled atmosphere. The samples will also be carefully investigated by SEM and X-ray diffraction.

Qualifications
Candidates should have a master's degree in engineering or a similar degree within Physics, Chemistry or Materials Science on an academic level equivalent to the master's degree in engineering. An absolute demand is very good communication skills in English, both written and spoken. Ability to work independently, to plan and carry out complex tasks, to perform complicated experiments, and to do theory based data analysis, are further necessary.

Approval and Enrolment
The scholarships for the PhD degree are subject to academic approval, and the candidates will be enrolled in one of the general degree programmes of DTU. For information about the general requirements for enrolment and the general planning of the scholarship studies, please see the DTU PhD Guide.

Assessment
The final assessment of the applicants will be made by the PhD Committee for Chemistry, Biotechnology and Chemical Engineering.

We offer
We offer an interesting and challenging job in an international environment focusing on education, research, public-sector consultancy and innovation, which contribute to enhancing the economy and improving social welfare. We strive for academic excellence, collegial respect and freedom tempered by responsibility. The Technical University of Denmark (DTU) is a leading technical university in northern Europe and benchmarks with the best universities in the world.

Salary and appointment terms
The salary and appointment terms are consistent with the current rules for PhD degree students. The period of employment is 3 years.

Workplace
The workplace will be DTU Energy, DTU Risø Campus, Frederiksborgvej 399, Roskilde, Denmark.

Further information 
Further information may be obtained from the supervisors, Professor, Peter Vang Hendriksen, tel. +45 4677 5725, e-mail pvhe.dtu.dk and Senior Researcher, Henrik Lund Frandsen, tel. +45 5668, e-mail hlfr@dtu.dk.

You can read more about the Department on www.energy.dtu.dk.

Please do not send applications to these e-mail addresses, instead apply online as described below.

Application
Please submit your online application no later than June 15, 2015. Applications must be submitted as one pdf file containing all materials to be given consideration. To apply, please open the link "Apply online," fill in the online application form, and attach all your materials in English in one pdf file. The file must include:

• A letter motivating the application (cover letter)
• Curriculum vitae
• Grade transcripts and BSc/MSc diploma (an official translation into English)
• Excel sheet with translation of grades to the Danish grading system (see guidelines and excel spreadsheet here)

Candidates may apply prior to ob­tai­ning their master's degree, but cannot begin before having received it.

All interested candidates irrespective of age, gender, race, disability, religion or ethnic background are encouraged to apply.

The Department of Energy Conversion and Storage is focused on education, research, and development within functional materials and their application in sustainable energy technologies. The Department, which has 230 employees, was founded in 2012 by bringing research groups from Risø DTU and DTU Chemistry together. We are present both at Risø Campus and Lyngby Campus.

DTU is a technical university providing internationally leading research, education, innovation and public service. Our staff of 5,700 advance science and technology to create innovative solutions that meet the demands of society; and our 10,000 students are being educated to address the technological challenges of the future. DTU is an independent academic university collaborating globally with business, industry, government, and public agencies.