Morphology, structural and electrical properties of nickel-oxide-yttria-stabilized-zirconia thin film for solid oxide fuel cell electrode application

Abstract

Achieving high quality electrode materials for efficient solid oxide fuel cell (SOFC) operation is challenging. SOFC requires porous electrode material. One of the common anode materials used is nickel oxide-yttria stabilized zirconia (NiO-YSZ). NiO-YSZ thin films were successfully deposited on glass substrates using sol-gel dip coating technique. The growth parameters considered were different coating layers (1, 2, 3 and 4 layers), different annealing temperature (300 °C, 400 °C, 500 °C and 600 °C) and different solution temperature (30 °C, 40 °C, 50 °C and 60 °C). The suspension was made from the mixture of NiO-YSZ powder and acetylacetone. All the prepared samples were characterized using X-ray diffraction (XRD), atomic force microscope (AFM), field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX) spectroscope, four point probe measurement and attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) spectrometer. The thickness of the thin films was measured using surface profiler. The XRD results showed that intensity increased at the Layer-3 as number of coating layers increased. From the FESEM and AFM analysis, the presence of porosity was clearly shown as the number of coating layers and annealing temperature increased. The presence of Ni, O, Y, Zr and Si elements were revealed using EDX spectroscope. The ATR-FTIR results show the presence of bonds at 780 cm-1, 940 cm-1 and 1230 cm-1 which correspond to Si-O, ZrO2 and Zr-O-Si bonding at solution temperature 30 °C. Overall, the present findings conclude that annealing, coating layers and solution temperature play vital role in producing beneficial quality NiO-YSZ thin films for solid oxide fuel cell (SOFC) anode.