CCS and Power Systems
Advanced Energy Systems - Solid Oxide Fuel Cells
Study of the Durability of Doped Lanthanum Manganite and Cobaltite Based Cathode Materials Under "Real World" Air Exposure Atmosphere
Performer: University of Connecticut
Project No: FE0009682
The University of Connecticut (UConn) team will perform an evaluation and analysis—using experimentation and computational simulation—of degradation phenomena in lanthanum manganite- and cobaltite-based cathode electrodes when exposed to air atmosphere conditions during solid oxide fuel cell (SOFC) operation. Specific study interests are product formation and interactions with air contaminants; dopant segregation and oxide exolution (i.e., release) at free surfaces; cation inter-diffusion and reaction product formation at the buried interfaces; inter-face morphology changes; lattice transformation and the development of interfacial porosity and micro-cracking; and delamination from the stack repeat units. The feasibility of the mitigation approaches will also be tested under accelerated conditions. Reaction processes will be studied via electrochemical and high temperature material compatibility tests followed by structural and chemical characterization. Degradation hypotheses will be proposed and validated through further experimentation and computational simulation of equilibrium interface atomic configurations at various processing conditions using first-principles thermodynamics, zero-temperature density functional theory with statistical mechanics, and high-accuracy measurements of lattice constants, rapid evaluation of the cation transport, and gas-solid phase interactions.
This project will examine the role of dopants, electric polarization, gas phase contaminants, oxygen stoichiometry (proportions), and A:B ratio on the long-term bulk and interfacial stability of lanthanum manganite and cobaltite cathodes. Cathode materials will be characterized to develop both initiation and propagation processes responsible for chemical and morphological changes. The role of electrode poisoning in the presence of chromium vapor will be examined using existing test facilities capable of generating a wide range of vapor pressures in humidified air.