H-titanate nanotube supported Fe_2O_3 nanoparticles for enhancing the thermal decomposition of ammonium perchlorate: The superb catalytic activity of interface sites

摘要

High surface area H-titanate nanotubes were synthesized through a hydrothermal route. Iron oxide (Fe2O3) was deposited on H-titanate nanotubes by atomic layer deposition (ALD) to produce H-titanate@Fe2O3 composites, which are used as combustion catalysts for thermal decomposition of ammonium perchlorate (AP). Results of thermal analysis show that H-titanate@Fe2O3 catalysts could effectively promote the thermal decomposition of AP. The decomposition temperature of AP is reduced by 96-111 degrees C with the presence of H-titanate@Fe2O3 catalysts, and the apparent activation energy is reduced by up to 117 kTmol(-1). The superb catalytic activity of Htitanate@Fe2O3 catalysts is attributed to the finely dispersed Fe2O3 nanoparticles anchored on the surface of Htitanate, which generate very active Fe2O3-H2Ti3O2 interface sites for the decomposition of AP. These results demonstrate the great potential of interface engineering as a promising strategy to prepare highly efficient propellant combustion catalysts. ALD has been proved to be an effective approach to synthesize catalytically active interface sites with optimum structures and performances.