TY - JOUR
T1 - Unravelling the structure and reactivity of supported Ni particles in Ni-CeZrO2 catalysts
AU - Gopalakrishnan, S.
AU - Faga, M. G.
AU - Miletto, I.
AU - Coluccia, S.
AU - Caputo, G.
AU - Sau, S.
AU - Giaconia, A.
AU - Berlier, G.
N1 - Funding Information:
Italian Ministry of the Environment and of the Territory and Sea Protection (MATT) is gratefully acknowledged for funding project METISOL. We thanks S. Morandi and G. Ghiotti for fruitful discussion, G. Gatti, from Dipartimento di Scienze ed Innovazione Tecnologica of Università del Piemonte Orientale for Raman measurements.
PY - 2013/7/7
Y1 - 2013/7/7
N2 - We report about the synthesis and characterisation of two NiCeZrO2 catalysts prepared by one pot-co-precipitation method. The two samples are characterised by similar chemical composition (15wt% Ni, Ce/Zr=80/20 atomic ratio) and properties of the CeZrO2 support, which is a cubic phase solid solution with nanometer sized (5-6nm) crystalline hexagonal/roundish particles. The main differences between the samples are in the NiO particles dispersion and surface area, which were found to be affected by the synthesis pH. Both samples were characterised about their surface properties by employing FTIR spectroscopy of adsorbed CO probe, and tested about their activity and stability in methane steam reforming (MSR) reaction at relatively low temperature (793K). The results show a good activity in MSR irrespective of the NiO size and morphology, with negligible CO formation, but a strong dependence of the catalysts stability upon these parameters. Only the catalyst with smaller (5-10nm) NiO particles was found stable for 250h in MSR at relatively high steam to carbon ratio (S/C=2). This performance could be related to a positive effect of the CeZrO2 support, allowing fast and easy oxygen transfer to and from the NiO/Ni0 active phase, most likely thanks to the occurrence of a strong metal-support interaction.
AB - We report about the synthesis and characterisation of two NiCeZrO2 catalysts prepared by one pot-co-precipitation method. The two samples are characterised by similar chemical composition (15wt% Ni, Ce/Zr=80/20 atomic ratio) and properties of the CeZrO2 support, which is a cubic phase solid solution with nanometer sized (5-6nm) crystalline hexagonal/roundish particles. The main differences between the samples are in the NiO particles dispersion and surface area, which were found to be affected by the synthesis pH. Both samples were characterised about their surface properties by employing FTIR spectroscopy of adsorbed CO probe, and tested about their activity and stability in methane steam reforming (MSR) reaction at relatively low temperature (793K). The results show a good activity in MSR irrespective of the NiO size and morphology, with negligible CO formation, but a strong dependence of the catalysts stability upon these parameters. Only the catalyst with smaller (5-10nm) NiO particles was found stable for 250h in MSR at relatively high steam to carbon ratio (S/C=2). This performance could be related to a positive effect of the CeZrO2 support, allowing fast and easy oxygen transfer to and from the NiO/Ni0 active phase, most likely thanks to the occurrence of a strong metal-support interaction.
KW - CeZrO
KW - FTIR spectroscopy
KW - Methane steam reforming
KW - Ni carbonyls
KW - Solar energy
UR - http://www.scopus.com/inward/record.url?scp=84875800030&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2013.02.036
DO - 10.1016/j.apcatb.2013.02.036
M3 - Article
SN - 0926-3373
VL - 138-139
SP - 353
EP - 361
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
ER -