UROP Proceedings 2020-21

School of Engineering Department of Mechanical and Aerospace Engineering 169 Electrochemical Characterization and Evaluation of Thin Film Cathodes for Solid Oxide Fuel Cells Supervisor: CIUCCI Francesco / MAE Student: CHAWLA Anhad Singh / SUSEE Course: UROP2100, Summer This progress report discusses the improvements achieved in the using of a new method Ultra-fast HighTemperature Sintering(UHS) on GDC symmetric cells. BaFe0.9Zr0.1O3-δ(BFZ) and BaFe0.9Zr0.1O2.9-δF0.1(BFZ-F) are used as cathodes and their UHS’d versions are compared to traditionally sintered BFZ. Optimal conditions achieved before are replicated with parameters that are more practical to the equipment used for UHS. Comparison of UHS and traditional furnace approaches to sintering the cathode are compared via Electrochemical Impedance Spectroscopy (EIR) to assess area specific resistance. Using the traditional method as a control reference, the UHS method shows definite improvement in lowered resistance, with Fluorine doped cathode showing even better performance. Fuel cell testing for other symmetric or half cells failed, preventing testing of UHS. Multidimensional Modeling of Nanoionics Supervisor: CIUCCI Francesco / MAE Student: PANG Ho Kiu Holdee / MAE Course: UROP1100, Fall Nanoparticle systems refers to systems that are made of nanoparticles, size ranging from 100nm to 500nm. In the past few decades, these systems are being utilized in various applications, including fuel cells, semiconductors and medical drug delivery, to name but a few, due to their unique properties. Nanoparticle have unique optical, electrostatic and mechanical properties that propelled the development of various new technologies in recent years. This project will be focusing on the electrostatic properties of nanoparticles and their impacts on solid fuel cells. To start with, a brief introduction of the principles of solid fuel cells will help us identify with the electrostatic responses of nanoparticles. A fuel cell1 is a device that utilizes chemical redox reaction to generate electricity, where main components includes a positive electrode called cathode and a negative electrode called anode and a solution called electrolyte, providing a medium for ionic exchange between the electrodes. Reduction reaction occurs in the cathode and oxidation rection occurs in the anode, which the combined effect causing the electrons to be utilized into generate a electric current, for example this is the basic reaction2 of a hydrogen fuel cell: 2H2 + O2  2H2O + 2e-. Now it can be seen why nanoionic materials are employed in battery technologies, the large exposed surface area of nanoparticles making their electrostatic interactions readily adjustable, by controlling factors like concentration of ions present in solution and surface charges.

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