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Catalytic oxidation of NO over TiO2 supported platinum clusters I. Preparation, characterization and catalytic properties

“…Since Pt{1 1 1} surface dominates in large platinum particles, it is proposed that large platinum particles are more active for NO oxidation than small particles. This is well supported by most experimental results reported [7,12,14]. In our opinion, however, the accessibility of Pt{1 1 1} in platinum catalysts is another very important issue to be considered.…”

“…Platinum catalysts have been extensively investigated in the past years [7][8][9][10][11][12][13][14] and up to now platinum catalysts are still regarded as model catalysts for NO oxidation. The catalytic and kinetic results for NO oxidation over platinum catalysts under different feed composition, e.g.…”

“…Besides, the catalyst support was found to influence the NO oxidation rate greatly and SiO 2 was better support than Al 2 O 3 and ZrO 2 . However, Denton et al [14] found that platinum particle size was key factor controlling the NO oxidation rate for both Pt/SiO 2 and Pt/Al 2 O 3 , while the impact of support was negligible. Further study of Olsson and Fridell [9] confirmed that NO oxidation rate decreased with decreasing platinum particle size and they explained this as small platinum particles more easily formed oxides.…”

Electrospinning of silica sub-microtubes mats with platinum nanoparticles for NO catalytic reduction

“…Nevertheless, only NO, N 2 , CO 2 and H 2 O were detected in the outlet gas stream up to 350ºC, indicating that the reacted NO was reduced to N 2 , while all the C 3 H 6 was oxidized to CO 2 and H 2 O. It is important to point out that one of the main drawbacks reported in the literature for platinum catalysts is the significant selectivity towards N 2 O [17][18][19][20][21][22]39,[41][42][43][44][45]. In the tested conditions, N 2 O was not detected, so its steady-state concentration, if any, would be less than 5 ppmv.…”

Characterization and Reactivity Analysis of Hydrogen Adspecies on Platinum Nano-particles Supported on Alumina

“…For example, Haruta 16) reported that the turnover frequencies (TOFs) of CO oxidation over Au/TiO2 sharply increased with decreasing diameter of Au particles from 4 nm and the Pt group metals showed a decreasing or steady TOF. Denton et al 18) investigated the influence of platinum dispersion on the activity of Pt/Al2O3 and Pt/SiO2 catalysts for NO reduction with propene, and reported that the intrinsic activity increased with decreasing platinum dispersion, suggesting that platinum dispersion is the key factor. Therefore, investigation of methods to control the particle size of noble metal and to understand the catalytic performance is very important.…”