정전슬러리분무증착법을 이용한 고체산화물 연료전지의 음극 기능층 미세구조 개선

Abstract

A SOFC composed of a thin Y2O3-ZrO3 (YSZ) electrolyte combined with a NiO-GDC anode would have less electronic conduction and improved catalytic activity at intermediate temperature. Due to the thermal mismatch between NiO-GDC anode pellet and YSZ electrolyte, NiO-YSZ anode functional layers (AFLs) were fabricated. The uniformly porous AFL is deposited on the NiO-GDC anode substrate by the electrostatic slurry spray deposition (ESSD). The thin and dense YSZ electrolyte is deposited onto the AFL. Thickness of 4, 6, 12, 25, 35 μm porous AFL was prepared and 25 μm thickness of AFL is optimized for intermediate temperature. The cells of these AFL layers had no detachment, crack, void or pore defects, and the constituent parts of the SOFCs were well adhered to NiO-GDC anode pellet and YSZ electrolyte. Also, uniformly dense GDC cathode interlayer (20μm thickness) and porous LSCF cathode layer (20 μm thickness) was deposited. The performances which are EIS, I-V curve of the prepared full cell were investigated at operating temperature range of 550 - 750 oC. It is confirmed that the polarization and activation energy of the thinner porous AFL are lower than the thicker porous AFL. The single cell with the optimized AFL showed power density 497 mW/cm2, 1.06 W/cm2, 1.55 W/cm2 at 550 oC, 650 oC, and 750 oC, respectively.