标题：Iron-based composite nanostructure catalysts used to produce COx-free hydrogen from ammonia
作者：Cui, Hui-Zhen; Gu, Ying-Qiu; He, Xin-Xin; Wei, Shuai; Jin, Zhao; Jia, Chun-Jiang; Song, Qi-Sheng
作者机构：[Cui Huizhen] School of Chemistry and Chemical Engineering, Shandong University, Key Laboratory for Colloid and Interface Chemistry of Education Minis 更多
通讯作者地址：[Jia, CJ; Song, QS]Shandong Univ, Key Lab Colloid & Interface Chem, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.
关键词：Composite nanostructures; Ammonia decomposition; In situ XRD; TPR
摘要：Iron-based composite nanostructures with ceria or titania as shell coating on naked iron spheres were successfully synthesized and used to catalyze ammonia decomposition. The structure and texture of fresh and used catalysts were characterized by transmission electron microscopy, X-ray diffraction, in situ X-ray diffraction, temperature-programmed reduction by hydrogen, and N-2 adsorption-desorption. For ammonia decomposition, the iron-based composite catalyst coated with cerium and titanium showed excellent catalytic activity compared with naked iron sphere catalyst, with the former yielding nearly 100% ammonia conversions at 650 degrees C and showing high stability in the catalysis test (for 60 h) at 600 degrees C with a space velocity of 24,000 cm(3) g(cat)(-1) h(-1). These results showed that adding cerium and titanium played a key role in improving catalytic activity for ammonia decomposition and enabling high thermal stability.