Morphology and Crystal-Plane Effects of Fe/W-CeO 2 for Selective Catalytic Reduction of NO with NH 3

摘要

The CeO 2 ordinary amorphous, nanopolyhedrons, nanorods, and nanocubes were prefabricated by the hydrothermal method, and employed as carriers of Fe/W–CeO 2 catalysts to selectively catalyze the reduction of NO with ammonia. Characterization results indicated that the morphology of CeO 2 support originated from selectively exposing different crystal surfaces, which has a significant effect on oxygen vacancies, acid sites and the dispersion of Fe 2 O 3 . The CeO 2 nanopolyhedrons catalyst (Fe/W–CeO 2 –P) showed most oxygen vacancies, the largest the quantity of acid sites, the largest BET (Brunauer-Emmett-Teller) surface area and the best dispersion of Fe 2 O 3 , which was associated with predominately exposing CeO 2 (111) planes. Consequently, the Fe/W–CeO 2 –P catalyst has the highest NO conversion rate in the temperature range of 100–325 °C among the ordinary amorphous, nanorods, and nanocubes Fe/W–CeO 2 catalysts.