TY - JOUR
T1 - COx-free hydrogen production from ammonia – mimicking the activity of Ru catalysts with unsupported Co-Re alloys
AU - Kirste, Karsten
AU - McAulay, Kate
AU - Bell, Tamsin E.
AU - Stoian, Dragos
AU - Laassiri, Said
AU - Daisley, Angela
AU - Hargreaves , Justin S.J.
AU - Mathisen, Karina
AU - Torrente-Murciano, Laura
N1 - Acceptance from webpage
OA article
PY - 2021/1
Y1 - 2021/1
N2 - On-demand production of hydrogen from ammonia is a challenge limiting the implementation of ammonia as a long term hydrogen vector to overcome the difficulties associated with hydrogen storage. Herein, we present the development of catalysts for the on-demand production of hydrogen from ammonia by combining metals with high and low N-adatom adsorption energies. In this way, cobalt-rhenium (Co-Re) catalysts show high activity mimicking that of ruthenium. EXAFS/XANES analyses demonstrate that the bimetallic Co-Re contribution is responsible for the activity and the stability of the catalysts in consecutive runs with no observable formation of nitrides (Co-N and Re-N) occurring under the ammonia atmosphere. While cobalt is partially re-oxidised under ammonia, re-reduction in the presence of rhenium is observed at higher temperatures, coinciding with the on-set of catalytic activity which is accompanied by minor structural changes. These results provide insight for the development of highly active alloy based ammonia decomposition catalysts.
AB - On-demand production of hydrogen from ammonia is a challenge limiting the implementation of ammonia as a long term hydrogen vector to overcome the difficulties associated with hydrogen storage. Herein, we present the development of catalysts for the on-demand production of hydrogen from ammonia by combining metals with high and low N-adatom adsorption energies. In this way, cobalt-rhenium (Co-Re) catalysts show high activity mimicking that of ruthenium. EXAFS/XANES analyses demonstrate that the bimetallic Co-Re contribution is responsible for the activity and the stability of the catalysts in consecutive runs with no observable formation of nitrides (Co-N and Re-N) occurring under the ammonia atmosphere. While cobalt is partially re-oxidised under ammonia, re-reduction in the presence of rhenium is observed at higher temperatures, coinciding with the on-set of catalytic activity which is accompanied by minor structural changes. These results provide insight for the development of highly active alloy based ammonia decomposition catalysts.
KW - ammonia; hydrogen; XAS; cobalt; rhenium
U2 - 10.1016/j.apcatb.2020.119405
DO - 10.1016/j.apcatb.2020.119405
M3 - Article
VL - 280
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
SN - 0926-3373
M1 - 119405
ER -