Reduction of NO by propene over supported iridium catalysts under lean-burn conditions: an in situ FTIR study

Hydrogenation of Citral Over IrAu/TiO2 Catalysts. Effect of the Preparation Method

“…Absorption bands in this region have been assigned to CO linearly adsorbed on different Ir 0 sites [23,24]. However, also in the spectral region 2000-2107 cm -1 , bands characterizing cationic iridium species are found [25][26][27]. The behavior of the CO band, shift to lower frequencies in HT sample, is consistent with an increase of reduced species after the high temperature treatment.…”

Hydrogenation of α,β-unsaturated carbonyl compounds over Au and Ir supported on SiO2

“…2000 cm −1 shows a contribution centered at 2042 cm −1 which could be assigned to linearly adsorbed CO species on low coordination Ir 0 sites [27]. On the other hand, bands characterizing cationic iridium species are also found in the spectral region 2000-2107 cm −1 [28][29][30]. Ir ı+ CO species have been identified by a CO band at ca.…”

“…Ir ı+ CO species have been identified by a CO band at ca. 2100 cm −1 on oxidized Ir/Al 2 O 3 after CO adsorption at room temperature [30]. The band at 2112 cm −1 may be related to CO adsorbed on remaining Ir ı+ species issued from an incomplete reduction of iridium.…”

3D atom probe study of gaseous adsorption on alloy catalyst surfaces III: Ternary alloys – NO on Pt–Rh–Ru and Pt–Rh–Ir

“…For automobile exhaust catalyst applications, both ruthenium and iridium are known to lower the light-off temperature for NO reduction compared to rhodium [11,12], while iridium has been shown to be active for NO reduction with propene under lean-burn conditions [13]. In an early study ruthenium demonstrated high selectivity for conversion of NO to N 2 [14], while more recent work has identified RuO 2 as the active component for CO oxidation rather than simple oxygen-covered Ru(0 0 0 1) surfaces [15].…”