Embedded iron nanoparticles by graphitized carbon as highly active yet stable catalyst for ammonia decomposition

The Fe nanoparticles embedded by graphitized carbon were developed through a strategy of hydrothermal and thermal treatment. The resulting materials, with high surface area and porosity, well dispersed iron nanoparticles (NPs) associated with graphitized carbon structure, show high activity and durability in ammonia decomposition reaction. Among the serial Fe-based catalysts, Fe@GC-4 of a low iron content (1.29 wt%) exhibits significant ammonia decomposition activity (similar to 71% conversion and 22.1 mol(H2) g(Fe)(-1) h(-1)) at a gas hourly space velocity of 6000 cm(3)g(cat)(-1) h(-1) and 600 degrees C. After an extended period of reaction conducted over the representative Fe@GC-3 catalyst, most of the embedded Fe NPs transform to nitride species with relatively smaller particle size, while the embedded structure still retains. This study provides new insights into the development of cheap metal-based catalysts functionalized by graphitized carbon (graphene) for the current reaction and other potential applications. (C) 2017 Elsevier S.V. All rights reserved.