Fig. 9 shows typical TEM images of reduced Pd(0.25)–Cu/SBA-15 catalyst, for which both of the two Pd–Cu alloy phases were observed from XRD pattern ( Fig. 6a). Fig. 9A reveals a representative image of 2D HS-173 of SBA-15. Fig. 9B and C exhibit an interesting dispersion of Pd–Cu alloy particles which align along with the 2D channels. The reason for this homogeneous and regular dispersion of Pd–Cu alloy particles can be attributed to the unique pore structure of SBA-15. Fig. 9D illustrates the distribution of particles sizes, which were derived by measuring about 150 particles. Particle sizes distribute primarily in the range of 5–8 nm, which is pulmonary vein reasonable as compared to the average value estimated from XRD (∼6 nm).
Fig. 9. TEM image (A) shows the characteristic pore structure of SBA-15. (B and C) are TEM images of reduced Pd(0.25)–Cu/SBA-15 (Cu = 10 wt%) with different areas. (D) represents the corresponding particle size distribution.Figure optionsDownload full-size imageDownload as PowerPoint slide