|Interconnected pinhole porosity and relatively low density of electrolyte thin films cause hindrance to perform the cross plane electric transport measurements to obtain ionic conductivity.
This project is aimed at obtaining the highly dense and pinhole free Gd doped CeO2 (CGO) thin films on larger and on different substrates (Si and MgO). The present project primarily emphasizes on understanding correlation between growth parameters, microstructure and electrical transport properties. Electrical transport measurements across the film thickness will be carried out on CGO films deposited at different growth conditions to realize the quality of thin films and subsequently evaluating ionic conductivity. Depending on the length of the project the student will be trained to deposit thin films by pulsed laser deposition (PLD), characterization by X-ray diffraction (XRD), microscopy (SEM/TEM), atomic force microscopy (AFM), dc and ac electrical transport measurements.
The Fuel Cells and Solid State Chemistry Division at Risø DTU is among the world’s research leaders in solid oxide fuel cells (SOFCs) – a technology for clean and efficient conversion of chemical energy (in the form of, e.g., natural gas, hydrogen, biogas, ammonia or methanol) into electricity and heat. An SOFC generally comprises a solid electrolyte layer with an oxidizer electrode (cathode) on one side of the electrolyte and a fuel electrode (anode) on the other side. The electrodes are required to be porous, or at least permeable to oxidizer at the cathode and fuel at the anode respectively, while the electrolyte layer is required to be dense so as to prevent leakage of gas across the layer. The electrolyte ionic resistance can be drastically reduced, thereby reducing the SOFC operating temperature by hundreds of degrees relative to conventional systems by reducing the thickness of the electrolyte layers. As a thin electrolyte film, we will use the CGO which possesses a good ionic conductivity at an operating temperature below 500oC.
Students with Physics/Materials science background
Thesis Final year project Term project Bachelor project
4 to 12 months
SOURCE : RISO
Thickness dependent Cross-plane electric transport measurements on Gd doped CeO2 thin films deposited by pulsed lased deposition (ABF-11)