Investigation of perovskite oxide SrFe0. 8Cu0. 1Nb0. 1O3-δ as cathode for a room temperature direct ammonia fuel cell

Abstract Through Pechini method, a single phase shuttle-shaped perovskite oxide SrFe 0.8 Cu 0.1 Nb 0.1 O 3 − δ was successfully synthesised at 1000 °C. It was combined with active carbon, forming a composite electrode to be used as cathode in a room temperature ammonia fuel cell based on an alkaline membrane electrolyte and Pt/C anode. Reasonable OCV and power density were observed for an ammonia fuel cell using SrFe 0.8 Cu 0.1 Nb 0.1 O 3 − δ /C composite cathode. Although the power density is not high enough for conventional portable or transport applications, it has the potential for stationary application in removal of ammonia from wastewater because the requirements on power density is relatively low. When a dilute 0.02 M ammonia solution (340 ppm) was used as the fuel, the fuel cell using this perovskite oxide can obtain an open circuit voltage of 0.35 V and a power density of 0.03 mW/cm2. In order to obtain higher OCV, NaOH is necessary to be added in the fuel, especially when the fuel contains a low concentration of ammonia. This study indicates that perovskite oxides are potential good cathode for low temperature direct ammonia or alkaline membrane fuel cells.