Scandium and copper co-doping effect on stability and activity to the NO direct decomposition of Ba3Y4O9

Direct decomposition of NO on Ba3Y4O9 doped with Cu and Sc was studied and it was found that co-doping of Sc and Cu into Ba3Y4O9 was effective for increasing both lattice stability and NO decomposition activity. In particular, Ba3Y3Sc0.6Cu0.4O9 (10 % Cu and 15 % Sc doping) catalyst showed N-2 and O-2 yield of 90 % and 99 %, respectively, in NO decomposition reaction at 700 degrees C. Comparing with the pristine and single-metal doped system, the optimized catalyst showed superior long-term stability and increased activity under O-2, and water vapor co-existence conditions because of the increased stability of crystal structure, improved lattice oxygen mobility and weakened oxygen adsorption on the surface. TPD and in-situ FT-IR results suggested that the co-doping effect was assigned to the easier removal of surface NO2- or NO3- species which blocks the active site to NO decomposition.