TY - JOUR

T1 - Microstructural characterization of Cu/ZnO/Al2O3 catalysts for methanol steam reforming-A comparative study

AU - Kurr, Patrick

AU - Kasatkin, Igor

AU - Girgsdies, Frank

AU - Trunschke, Annette

AU - Schlögl, Robert

AU - Ressler, Thorsten

PY - 2008/10/15

Y1 - 2008/10/15

N2 - Microstructural characteristics of various real Cu/ZnO/Al2O3 catalysts for methanol steam reforming (MSR) were investigated by in situ X-ray diffraction (XRD), in situ X-ray absorption spectroscopy (XAS), temperature programmed reduction (TPR) and electron microscopy (TEM). Structure-activity correlations of binary Cu/ZnO model catalysts were compared to microstructural properties of the ternary catalysts obtained from in situ experiments under MSR conditions. Similar to the binary system, in addition to a high specific copper surface area the catalytic activity of Cu/ZnO/Al2O3 catalysts is determined by defects in the bulk structure. The presence of lattice strain in the copper particles as the result of an advanced Cu-ZnO interface was detected only for the most active Cu/ZnO/Al2O3 catalyst in this study. Complementarily, a highly defect rich nature of both Cu and ZnO has been found in the short-range order structure (XAS). Conventional TPR and TEM investigations confirm a homogeneous microstructure of Cu and ZnO particles with a narrow particle size distribution. Conversely, a heterogeneous microstructure with large copper particles and a pronounced bimodal particle size distribution was identified for the less active catalysts. Apparently, lattice strain in the copper nanoparticles is an indicator for a homogeneous microstructure of superior Cu/ZnO/Al2O3 catalyst for methanol chemistry.

AB - Microstructural characteristics of various real Cu/ZnO/Al2O3 catalysts for methanol steam reforming (MSR) were investigated by in situ X-ray diffraction (XRD), in situ X-ray absorption spectroscopy (XAS), temperature programmed reduction (TPR) and electron microscopy (TEM). Structure-activity correlations of binary Cu/ZnO model catalysts were compared to microstructural properties of the ternary catalysts obtained from in situ experiments under MSR conditions. Similar to the binary system, in addition to a high specific copper surface area the catalytic activity of Cu/ZnO/Al2O3 catalysts is determined by defects in the bulk structure. The presence of lattice strain in the copper particles as the result of an advanced Cu-ZnO interface was detected only for the most active Cu/ZnO/Al2O3 catalyst in this study. Complementarily, a highly defect rich nature of both Cu and ZnO has been found in the short-range order structure (XAS). Conventional TPR and TEM investigations confirm a homogeneous microstructure of Cu and ZnO particles with a narrow particle size distribution. Conversely, a heterogeneous microstructure with large copper particles and a pronounced bimodal particle size distribution was identified for the less active catalysts. Apparently, lattice strain in the copper nanoparticles is an indicator for a homogeneous microstructure of superior Cu/ZnO/Al2O3 catalyst for methanol chemistry.

KW - Cu lattice strain

KW - Cu/ZnO/AlO catalyst

KW - Homogeneous microstructure

KW - Hydrogen production

KW - In situ

KW - Methanol steam reforming

KW - TEM

KW - TPR

KW - XAS

KW - XRD

UR - http://www.scopus.com/inward/record.url?scp=50649098258&partnerID=8YFLogxK

U2 - 10.1016/j.apcata.2008.06.020

DO - 10.1016/j.apcata.2008.06.020

M3 - Article

AN - SCOPUS:50649098258

VL - 348

SP - 153

EP - 164

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

SN - 0926-860X

IS - 2

ER -