?-Al2O3 supported silver nanoparticle applied in C3H8-SCR: Nanosphere and nanoflake

The gamma-Al2O3 support (nanosphere and nanoflake) was used to support Ag nanoparticles and applied in C3H8-SCR to remove NOx. Ag/Al2O3-flake exhibited superior catalytic activity than Ag/Al2O3-sphere in C3H8-SCR. It is found that Al2O3-flake rich in Al octacoordinated ions promoted more Agn delta+ species to disperse on Ag/Al2O3-flake than Ag/Al2O3-sphere. Agn delta+ species could strengthen the low-temperature catalytic activity for HC-SCR while Ag metal particles were unbeneficial since they could promote complete oxidation of hydrocarbon. This was the first time to explore the remarkable effect of Al2O3 intrinsic properties on catalytic activity of alumina-supported catalyst for HC-SCR from the perspective of uniform morphology.Environmental implication: The number of transport vehicles has increased dramatically during the past decades due to global economic growth. The accompanying concern is the huge consumption of fossil fuels, for example, gasoline and diesel, which speeds up global warming. Internal combustion engines produce toxic emissions, where NOx forms nitric acid in the atmosphere, reacts with HCs to form which causes acidification of land and lakes. Currently, it is urgent to develop a leading deNOx technique for the after-treatment of commercial engine-powered vehicles to meet stringent emission legislations.

Automated summary

The γ-Al2O3 support was used to support Ag nanoparticles, and the Ag/Al2O3-flake exhibited superior catalytic activity in C3H8-SCR compared to Ag/Al2O3-sphere. The Al2O3-flake with more Al octacoordinated ions promoted the dispersion of Agn δ+ species on Ag/Al2O3-flake. The Agn δ+ species strengthened the low-temperature catalytic activity for HC-SCR, while Ag metal particles were unbeneficial.