Compatibility study of La2NiO4+delta and La2Mo1.5W0.5O9 as electrode-electrolyte material for solid oxide fuel cell

The present work investigates the chemical compatibility of La2NiO4+delta (LN) and La2Mo1.5W0.5O9 (W-LMO) as cathode/electrolyte and NiWO4 (NW)/La2Mo2O9 (LMO) as anode/electrolyte material for solid oxide fuel cell (SOFC) application respectively. The x- ray diffraction (XRD) study of LN/W-LMO shows the existence of five phases viz., La2NiO4+delta, La2Mo1.5W0.5O9, NiWO4, NiO and La1.77Mo1.77O8.001. Whereas, the XRD analysis of NW/LMO shows the formation of NiO, higher order molybdates viz., La5Mo4O14 and La12Mo6O35 as a result of partial Mo reduction. The formation of NiWO4 as a secondary phase in La2NiO4+delta/La2Mo1.5W0.5O9 is a potential anode material which is studied with La2Mo2O9 as anode/electrolyte by x-ray photoelectron spectroscopy (XPS). The XPS analysis of NW/LMO in Ar-H-2 atmosphere reveals the partial reduction of Mo to lower oxidation states. The presence of NiWO4 is also verified by Raman spectroscopy with peaks at 698, 778 and 891 cm(-1) with the signatures of W-LMO and Mo-O bonding