Excellent low temperature NH3-SCR activity over MnaCe0.3TiOx (a = 0.1–0.3) oxides: Influence of Mn addition

Preparation of Mesoporous Mn–Ce–Ti–O Aerogels by a One-Pot Sol–Gel Method for Selective Catalytic Reduction of NO with NH3

“…The deconvolution of Mn 2p1/2 peak could obtain three peaks assigned to Mn 2+ (652.4 ± 0.2 eV), Mn 3+ (653.8 ± 0.3 eV), and Mn 4+ (654.9 eV ± 0.4), The Mn 2p3/2 could also be divided into three peaks ascribed to Mn 2+ (641.1 ± 0.2 eV), Mn 3+ (642.6 ± 0.3 eV), and Mn 4+ (644.1 ± 0.4 eV) [20,21]. The XPS spectra of Ce 3d in The two peaks, u and v , were attributed to Ce 3+ species, whereas another six peaks belonged to Ce 4+ species [14,38]. Two peaks, at~464.5 eV and~458.7 eV, were observed for the XPS spectra of Ti 2p, as shown in Figure 5c, which were attributed to Ti 2p3/2 and Ti 2p1/2, respectively, representing the characteristic Ti 4+ species [11,14].…”

“…To compare the intrinsic activity of the catalysts at different calcination temperatures, turnover frequency (TOF) was calculated using Equation (5) [14,35]. TOF represents the number of NO conversion at a single active site (Mn atom) per unit time; its value is a measure of the catalytic reaction rate on a catalyst.…”

“…The NH 3 -SCR process on the MCTO-600 catalyst follows both the Eley-Rideal (E-R) mechanism and the Langmuir-Hinshelwood (L-H) mechanism.In addition, the V-based catalysts have some inevitable disadvantages, such as the toxicity of VO x , a narrow operating temperature window (300-400 • C), and a low N 2 selectivity [6,14,15]. Therefore, it is of great practical importance to develop catalysts with high catalytic activity and good SO 2 resistance under low-temperature conditions (<200 • C).The MnO x -based catalysts have been considered as promising candidates for NO removal by the NH 3 -SCR method owing to their inherent environmentally benign nature and superior catalytic activity [13][14][15][16][17][18][19][20][21]. As an additive, CeO 2 can further enhance the catalytic activity of MnO x in the low temperature range because of its unique oxygen storage capacity and redox performance [22,23].…”

“…In addition, the V-based catalysts have some inevitable disadvantages, such as the toxicity of VO x , a narrow operating temperature window (300-400 • C), and a low N 2 selectivity [6,14,15]. Therefore, it is of great practical importance to develop catalysts with high catalytic activity and good SO 2 resistance under low-temperature conditions (<200 • C).…”

“…The MnO x -based catalysts have been considered as promising candidates for NO removal by the NH 3 -SCR method owing to their inherent environmentally benign nature and superior catalytic activity [13][14][15][16][17][18][19][20][21]. As an additive, CeO 2 can further enhance the catalytic activity of MnO x in the low temperature range because of its unique oxygen storage capacity and redox performance [22,23].…”