Applied Catalysis B: Environmental, Vol.220, 283-289, 2018
Cogeneration of ethylene and energy in protonic fuel cell with an efficient and stable anode anchored with in-situ exsolved functional metal nanoparticles
In situ exsolution of Co nanoparticles on perovskite framework has been successfully synthesized by firing the porous precursor SrMo0.8Co0.1Fe0.1O3-delta (SMCFO) in reducing flow at 850 degrees C. A structure transformation (from mixed to pure cubic phase) and the growth of Co nanoparticles are observed in H-2 atmosphere. This leads to an increase in the oxygen vacancy content, which is beneficial to the electrical conduction and catalytic activity towards the oxidations of H-2 and C2H6. Moreover, this material exhibits good redox reversibility under the condition of multiple reduction and re-oxidation cycles, as confirmed by the thermogravimetric analysis (TGA) measurements. A protonic fuel cell (PFC) built with this newly developed material shows a comparable electrocatalytic activity in both C2H6 and H-2 atmospheres while a considerably high power density of 377 mW cm(-2) is achieved in H-2 and 268 mW cm(-2) in C2H6 at 750 degrees C. In addition, C2H4 yield in the cell with Co-SMCFO as anode is considerably improved (11.9%-37.8% at 650-750 degrees C) with respect to the widely used chromium oxide. The good electrochemical performance, the improved C2H6 partial dehydrogenation ability and the negligible carbon formation in the Co-SMCFO anode are the strong indications that the SMCFO is a promising catalyst for the cogeneration of C2H4 and electricity, and can also be potentially utilized in the PFC directly fueled with hydrocarbon.