A MORE EFFICIENT ANODE MICROSTRUCTURE FOR SOFCs BASED ON PROTON CONDUCTORS

Journal Article · · International Journal of Hydrogen Energy

DOI:https://doi.org/10.1016/j.ijhydene.2012.09.027· OSTI ID:1080964

Rainwater, Ben H; Liu, Mingfei; Liu, Meilin

While the desired microstructure of the state-of-the-art Ni-YSZ anode for a solid oxide fuel cell (SOFC) based on YSZ is well known, the anode microstructure for a SOFC based on a proton conductor is yet to be optimized. In this study, we examined the effect of anode porosity on the performance of a SOFC based on BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3-δ (BZCYYb), a mixed ion (proton and oxygen anion) conductor with high ionic conductivity at intermediate temperatures. Three cells with Ni-BZCYYb cermet anodes of different porosities (37%, 42%, and 50%) and identical electrolytes and cathode components were fabricated and tested. Under typical fuel cell operating conditions, the cell with anode of the lowest porosity (37%), prepared without pore former, achieved the highest performance, demonstrating a peak power density of 1.2 W/cm² at 750 °C. This is radically different from the results of Ni-YSZ anodes for YSZ based cells, where high anode porosity (~55%) is necessary to achieve high performance. The observed increase in performance (or electrocatalytic activity for anode reactions) is attributed primarily to the unique microstructure of the anode fabricated without the use of pore forming precursors.

• Research Organization: Energy Frontier Research Centers (EFRC); Heterogeneous Functional Materials Center (HeteroFoaM)
• Sponsoring Organization: USDOE SC Office of Basic Energy Sciences (SC-22)
• DOE Contract Number: SC0001061
• OSTI ID: 1080964
• Journal Information: International Journal of Hydrogen Energy, Journal Name: International Journal of Hydrogen Energy
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
36 MATERIALS SCIENCE
carbon sequestration
catalysis (heterogeneous)
charge transport
energy storage (including batteries and capacitors)
hydrogen and fuel cells
materials and chemistry by design
mechanical behavior
membrane
synthesis (novel materials)
synthesis (scalable processing)
synthesis (self-assembly)