Catalytic properties of Ni-Fe-Mg alloy nanoparticle catalysts for methanol decomposition

• Published in: Catalysis today Vol. 281; pp. 669 - 676
• Main Authors: Mitani, Haruka, Xu, Ya, Hirano, Toshiyuki, Demura, Masahiko, Tamura, Ryuji
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2017
• Subjects: Hydrogen production; Methanol decomposition; Ni-Fe-Mg alloy nanoparticles; Ni3Fe; Thermal plasma method; Methanol decomposition; Thermal plasma method; Ni-Fe-Mg alloy nanoparticles; Ni3Fe; Hydrogen production
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2016.10.036

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•Ni-15Fe-13Mg nanoparticles showed much less carbon deposition in methanol decomposition than Ni-25Fe nanoparticles.•The sample including Mg showed 30% higher conversion in methanol decomposition than Ni-25Fe nanoparticles.•The addition of Mg significantly suppressed the coarsening process of alloy nanoparticles during the reaction.
Ni-25Fe and Ni-15Fe-13Mg (at.%) alloy nanoparticles were fabricated by a thermal plasma method, and their catalytic properties for methanol decomposition were examined in the 513–793K temperature range. Both nanoparticles started showing activity for methanol decomposition above 593K, with activity rapidly increasing with temperature. Ni-15Fe-13Mg showed much higher activity and less carbon deposition than Ni-25Fe. These results indicated that the addition of Mg in the Ni-Fe alloy significantly increased the activity, but suppressed carbon deposition. Characterization of the nanoparticles revealed that the Mg was segregated and a thin layer of MgO was formed on the surface of the nanoparticles. It is likely that the formation of MgO suppressed carbon deposition, but enhanced the activity by delaying the coarsening of nanoparticles during the reaction.