Effect of N-doping and carbon nanostructures on NiCu particles for hydrogen production from formic acid

• Published in: Applied catalysis. B, Environmental Vol. 298; p. 120604
• Main Authors: Carrales-Alvarado, D.H., López-Olmos, C., Dongil, A.B., Kubacka, A., Guerrero-Ruiz, A., Rodríguez-Ramos, I.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.12.2021; Elsevier BV
• Subjects: Carbon; Carbon supports; Catalysts; Doping; Formic acid; Formic acid dehydrogenation; Graphene; Hydrogen production; Low temperature; Metal particles; Morphology; Multi wall carbon nanotubes; Nanostructure; Nanotechnology; Nanotubes; Nickel-copper catalysts; Nitrogen doping; Single wall carbon nanotubes; Xerogels; Nitrogen doping; Formic acid dehydrogenation; Carbon supports; Hydrogen production; Nickel-copper catalysts
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2021.120604

[Display omitted] •Hydrogen has been obtained through formic acid decomposition at mild temperatures with non-noble supported Ni-Cu catalysts.•Pyrrolic nitrogen can promote the reaction.•More conductive carbon nanostructures favour the reduction of metals.•The metal-nitrogen interaction does not promote the reaction.•The best catalyst is NiCuNCNT due to the higher ratio of pyrrolic nitrogen. A series of NiCu based catalysts were prepared using different carbon nanostructure as support and loading 2.5 wt% of each metal. The studied nanocarbon materials were: reduced graphene oxide (rGO), N-doped reduced graphene oxide (NrGO), high surface area graphite (HSAG), single and multiwalled carbon nanotubes (SWCNT and MWCNT), N-doped carbon nanotubes (NCNT), spheres of xerogel carbons (SXC) and N-doped SXC (NSXC). The effect of N-doping, electronic properties and morphology of the carbon nanostructures on the metallic particle size was studied as well as their capacity to produce high purity hydrogen from formic acid decomposition at low temperature. The NiCu based catalysts tested are highly selective to H2 (98−94 % at conversions above 95 %). The site time yield (STY) of the catalysts follows the order: NCNT > SXC > SWCNT∼HSAG∼rGO10>rGO325>MWCNT∼NSXC > NrGO325>NrGO10, indicating that N-doped catalysts are less active, except in the case of NCNT which is ascribed to the N-pyrrolic heteroatoms of this material.