N2O decomposition over K-promoted Co-Al catalysts prepared from hydrotalcite-like precursors

Nitrous Oxide Decomposition Over MCO3–Co3O4 (M = Ca, Sr, Ba) Catalysts

“…Ohnishi et al [19] have recently reported the role of alkali and alkaline earth metals doping in enhancing the N 2 O decomposition activity of Co 3 O 4 spinel oxide catalyst. Concurrent with this study, the positive influence of alkaline metals during N 2 O decomposition was also reported for other catalytic systems like Co 3 O 4 -CeO 2 [13], Co-Al [29], CuO [38], NiO [39], and Rh/Al 2 O 3 [10,11] catalysts. In the pervious references, it was argued that the alkali metal content plays a vital importance in enhancing the N 2 O decomposition activity.…”

“…2). Similar to the role of the K in enhancing N 2 O decomposition over K-Co 3 O 4 [22] and K-Co-Al [29], we can suggest that the presence of Sr 2? an Ba 2?…”

“…nitrogen and oxygen. Wide variety of catalysts were tested such as metal surfaces [8], supported metals [9][10][11], metal oxides [12,13], supported oxides [14,15], ternary oxides [16], spinels [13,[17][18][19][20][21][22][23][24][25], perovskites [26] hydrotalcites [27][28][29], and zeolites [30][31][32][33][34][35][36][37]. Focusing our attention to spinel oxide catalysts, a high laugh gas decomposition activity was reported for cobalt containing spinel oxides, such as Co 3 O 4 .…”

An influence of thermal treatment conditions of hydrotalcite-like materials on their catalytic activity in the process of N2O decomposition

“…These authors suggested also that the low electronegativity of potassium may promote the electron transition from the active site to antibonding orbital of N 2 O and therefore facilitate the breaking the N-O bound. Similar mechanism of the potassium promotion effect was suggested by Cheng et al [35] for the Co-Al catalysts prepared from hydrotalcite-like precursors.…”

Effect of Ir crystallographic site on the catalytic performance of Ir-substituted barium hexaferrites for N2O decomposition

“…Moreover, oxygen in the mirror plane resides as a monatomic layer that has been shown to be less tightly bound than oxygen present in the spinel block in both Ba-hexaaluminate (␤-Al 2 O 3 ) and Ba-hexaferrite (MP), providing a preferential path for the diffusion of oxide ions [43][44][45][46]. Therefore, the lattice oxygen in the mirror plane was much easier to move and diffuse, thus greatly facilitating the desorption of surface oxygen generated by the dissociative adsorption of N 2 O on the adjacent Ir ions in 4f 2 sites, since the oxygen desorption is generally regarded as rate-determining step for N 2 O decomposition process [8,[47][48][49]. Therefore, Ir ions in 4f 2 sites in the preferentially exposed mirror plane and close to the active oxygen were highly active for N 2 O decomposition.…”