Achieving Robust Redox Stability of SOFC through Ni-YSZ Anode Layer Thinning and Inert Support Mechanical Compensation

Abstract

The reduction/oxidation (redox) instability of a Ni-based anode during fuel-rich and fuel-lean cycling conditions has been considered as one of the critical factors hindering the widespread application of solid oxide fuel cells (SOFCs). In this work, we report a redox-robust tubular SOFC with a thick porous 3Y-TZP support and a thin Ni-YSZ functional anode layer. The peak power density of the 3Y-TZP supported SOFC is 0.25 W cm–2 at 800 °C in hydrogen, and stable operation under different discharge current levels is achieved. The 3Y-TZP supported tubular SOFC survives from seven redox cycles as well as subsequent 100 h of constant current discharge without performance degradation. The high redox stability of the 3Y-TZP supported tubular SOFC is mainly attributed to the combined mechanism of slow oxidation rate, less generated tensile stress, and mechanical strength compensation from the support.

Smart Dual‐Exsolved Self‐Assembled Anode Enables Efficient and Robust Methane‐Fueled Solid Oxide Fuel Cells

“…The free energy of a gas phase molecule or an adsorbate on the surface was calculated by the equation G = E + ZPE − TS, where E is the total energy, ZPE is the zero‐point energy, T is the temperature in kelvin (298.15 K is set here), and S is the entropy. The standard hydrogen electrode (SHE) model [ 4 ] was adopted in the calculations of Gibbs free energy changes (Δ G ) of all reaction steps, which was used to evaluate the reaction barrier.…”

“…[ 3 ] Moreover, the volume change during redox cycles and the Ni coarsening during the long‐term operation of Ni‐based ceramic anodes also restrict the energy efficiency and operating life of SOFCs. [ 4 ]…”

Effect of NiO Addition on the Sintering and Electrochemical Properties of BaCe0.55Zr0.35Y0.1O3-δ Proton-Conducting Ceramic Electrolyte

“… ( a ) I–V and I–P diagrams of the single cell with a structure of NiO-BCZY/BCZY-0.5/BCZY–LSCF at 600–700 °C, ( b ) EIS diagram, ( c ) the corresponding EIS of the complete single cell measured under open circuit conditions, ( d ) cross section view of the single cell after testing, ( e ) comparison of MPDs of SOFCs based on H + and O 2− conductors [ 29 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ], and ( f ) durability test of the cell at 650 °C and 0.7 V. …”

Crack-Free Fabrications of Yttria-Stabilized Zirconia Films Using Successive-Ionic-Layer-Adsorption-and-Reaction and Air-Spray Plus Method

“…[1][2][3][4] In Particular, solid oxide fuel cells (SOFCs) demonstrate high conversion efficiency through an electrochemical route. [5][6][7] Yttria-stabilized zirconia (YSZ), known for its excellent O 2conductivity, as well as thermal, chemical, and mechanical stability, is widely employed as an electrolyte in SOFCs. [1][2][3][4][5][6][7] Among the cubic, tetragonal, and monoclinic phases of YSZ compounds, cubic YSZ is commonly preferred in fuel-cell devices due to its rapid O 2diffusion and slow cation diffusion.…”