Structure-Function Correlations for Ru/CNT in the Catalytic Decomposition of Ammonia

formations. Our previous work on CNT-supported FeCo alloy nanoparticles for ammonia decomposition revealed that the structural confinement improves the stability rather than the intrinsic activity. [11] We herein present a preliminary study on the structural effects of CNTs when used as supports for Ru nanoparticles, and on the localization of Ru nanoparticles on ammonia. CNTs used as supports were annealed at 450, 900, and 15008C (denoted as C450, C900, and C1500, respectively) to increase the graphitization degree (electron donating ability) of the walls and to remove impurities (i.e., modify the chemistry of Ru–support interactions). Ru nanoparticles were placed inside or outside of the CNTs (denoted as Ru-in and Ruout, respectively) to sense a possible confinement effect. Table 1 summarizes the main physical properties of the CNT supports and Ru catalysts. The effects of the calcination temperature on the textural characteristics of CNT supports and on 2 wt % Ru/CNTs samples were studied by N2 adsorption–desorption measurements. All samples exhibited type V isotherms with H3 hysteresis loops, indicating that the catalysts have capillary pores. The Brunauer–Emmett–Teller (BET) surface area of C1500 was lower than those of C900 and C450, which is due