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In this study, three kinds of CuAl-LDO/CNT (LDO, layered double oxide) catalysts were prepared by the assembly of CNTs and CuAl-LDH (LDH, layered double hydroxides) as well as subsequently structural topological transformation. The effects of the assembly method on the surface structure property and the DeNO x performance of the prepared samples were systematically investigated. It was found that three CuAl-LDO/CNT catalysts showed preferable NH 3 -SCR catalytic performance compared with CuAl-LDO where the catalyst CuAl-LDO/CNTs(I) exhibited optimum NO x conversion (>80%) and N 2 selectivity (>90%) within 180−300 °C. Such fine catalytic performance can be attributed to the proper surface acidity and redox ability of the catalyst, which might be correlated with the high dispersion of Cu-based active centers caused by the induced nucleation and effective separation action of LDH by carbon nanotubes. In addition, the outstanding H 2 O and SO 2 resistance of the CuAl-LDO/CNTs(I) catalyst was also obtained because of the synergistic effect between CuAl-LDO and CNTs, which could greatly promote the activation and decomposition of ammonium sulfate at lower temperatures.

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A series of Ni4‐xMnxTi1Oy mixed metal oxides (Ni4‐xMnxTi1‐LDO) catalysts originated from layered double hydroxides (LDHs) were fabricated and evaluated in the selective catalytic reduction of NO with NH3 (NH3‐SCR). To optimize the denitrification performance, the redox capability of catalysts was adjusted by calcining the Ni4‐xMnxTi1‐LDHs precursors with different Mn loading at different temperatures. The results revealed that calcination temperature was the secondary factor while the molar ratio of Mn to Ni was the main factor for influencing the redox properties. Among Ni4‐xMnxTi1‐LDO catalysts, the Ni2Mn2Ti1‐LDO catalyst afforded the optimal DeNOx behavior with above 90 % NOx conversion and 95 % selectivity of N2 as well as superior SO2 resistance in the wide temperature region of 150–360 °C. Multiple characterizations indicated that exceptional catalytic performance of Ni2Mn2Ti1‐LDO catalyst was highly dependent on the suitable redox capability resulted from moderate concentration of Ni3+, Mn4+ and chemisorbed oxygen Oβ in catalysts surface.