Synthesis and performance of ceria-zirconia supported Ni-Mo nanoparticles for partial oxidation of isooctane

Abstract

Catalyst deactivation due to sintering and carbon deposition is one of the main issues associated with electrocatalysis and catalytic hydrocarbon reforming over supported Ni catalysts. We report a Ni-Mo bimetallic catalyst supported on ceria-zirconia (CZ) prepared using co-impregnation as an efficient catalyst for partial oxidation of isooctane at high space velocities. It is also used as a catalytic micro-reforming layer on a conventional Ni/YSZ-based solid oxide fuel cell (SOFC) to form a bi-layer anode. The catalysts were characterized using a number of analytical techniques and catalyst performance for partial oxidation of isooctane was investigated at 750 degrees C; atmospheric pressure; air and fuel flow rates of 100 sccm and 3 ml/h, respectively; and O-2/C ratio of 0.4. The addition of Mo increases the catalytic activity in terms of isooctane conversion and syngas yields. Most significantly, the presence of Mo enhances the long-term stability of the Ni-based catalyst. Molybdenum strengthens the interaction between Ni and the support and improves the overall metal dispersion. We have further demonstrated that the carbon tolerance of Ni can be significantly improved by Mo addition. When applied it as a reforming layer in a SOFC running on isooctane, the cell showed a very slow degradation rate of 4.8 mV h(-1) during 12 h of operation at 750 degrees C. The excellent catalytic activity and stability suggest that Ni-Mo/CZ is an excellent material for a bi-layer anode of SOFC with superior coke tolerance. (C) 2017 Elsevier B.V. All rights reserved.