Hydrogen production by catalytic decomposition of methane over Ni-Cu-Co alloy particles

摘要

A series of Ni-Cu-Co alloy catalysts with different atomic compositions were prepared by the thermal decomposition of fibrous Ni-Cu-Co oxalate precursors in methane atmosphere. The resulting porous aggregates of Ni-Cu-Co alloy particles, with crystalline sizes ranging from 12.6 to 15.9nm, showed good catalytic activities for methane decomposition in the temperature range from 650 to 775 °C The percent composition of the constituent metals in the Ni-Cu-Co alloy catalyst was a dominant parameterthat could affect the catalytic activity of the catalyst. When compared with the Ni-Cu alloy, the addition of cobalt was found to inhibit the quasi-liquid phenomenon effectively. With increasing cobalt content, the catalyst stability at higher temperature was improved but further continual increase of cobalt content led to phase separation as evidenced by the X-ray diffraction (XRD) patterns. The mechanism for the stabilizing effect of cobalt is discussed. The textural properties of the carbon nano-fibres were characterized by transmission electron microscopy and XRD.