Decomposition of Methane over a Ni−Cu−MgO Catalyst to Produce Hydrogen and Carbon Nanofibers

• Published in: The journal of physical chemistry. B 2004-12, Vol.108 (52), p.20273-20277
• Main Authors: Wang, Haiyou, Baker, R. Terry K
• Format: Article
• Language: English
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp040496x

We have found that a Ni−Cu−MgO catalyst maintained its activity for the decomposition of methane at high levels for substantially long periods of time at 665−725 °C, being capable of generating large amounts of CO-free H2 and solid carbon. TEM examinations revealed that the solid carbon consisted exclusively of nanofibers possessing a “platelet” structure, in which the graphite layers are aligned in a direction perpendicular to the axis of the fiber. In sharp contrast, the Ni−MgO−methane system exhibited negligible activity at temperatures ≥650 °C. XRD and H2 chemisorption characterizations indicated that after reduction a Ni−Cu alloy was formed in the Ni−Cu−MgO catalyst and the surface of the particles was enriched in Cu0. A possible explanation for the observed superiority of the Ni−Cu−MgO catalyst over that of the Ni−MgO system is presented.