Catalytic Reduction of NOX Over TiO2–Graphene Oxide Supported with MnOX at Low Temperature

TiO2–graphene oxide (TiO2–GO) nanocomposites were prepared by the sol–gel method with different mass ratios of GO. The MnOX active components were loaded by means of ultrasonic impregnation. The catalysts exhibited excellent physical structures and electron transfer properties, which favored the catalytic activity. All of the catalysts were characterized by FESEM, XRD, TEM, BET, FT-IR, and XPS. The catalytic reduction activities of NOX were studied under low temperature conditions using ammonia as the reductant. Results indicated GO formation in the TiO2–GO supports, which reveals that TiO2–GO can be readily indexed as anatase TiO2 in all samples. Various valence states of manganese species coexisted in the MnOX/TiO2–GO catalysts. Non-stoichiometric (MnOX/Mn) on the surface of the composite catalysts was particularly beneficial to electron transfer, resulting in good redox performance. The optimum mass ratio of Mn in MnOX/TiO2–0.8 % GO was 9 wt%, and catalyst with this amount of Mn exhibited good resistance to H2O and SO2. All of the samples showed excellent N2 selectivity. The surface of the GO sheets is covered by a uniform layer of MnOX which increasing the activity of the catalyst by 9 % MnOX/TiO2–0.8 % GO.