Theoretical Study on Nano-Catalyst Burn Rate

Abstract : This research involved using highly accurate theoretical models to investigate the role of transition metal nano-catalysts as burn rate modifiers in composite energetic materials. Periodic density functional calculations were used to probe ammonium perchlorate adsorption on surfaces and clusters. Both TiO2 surfaces of rutile and anatase phases were constructed and their energetic and thermodynamic stability to understand electronic properties and reactivity of the most stable surface structures. Interaction of ammonium perchlorate (AP) with the most stable surface structures was determined and mechanism of AP decomposition investigated. The effect of transition metal doping on cluster stability and reactivity of TiO2-based nanoparticles showed that Fe and Co doping stabilized the small cluster of TiO2 anatase (1 nm) and the larger stabilization effect was found in the case of Fe doping. The effect of oxygen vacancy on the catalytic activity of TiO2 clusters was also investigated. The anatase clusters with oxygen vacancy showed higher catalytic activity toward AP adsorption. Analysis of the mechanism of AP decomposition on TiO2 nanoparticles revealed that the decomposition process is complicated involving many intermediate species, which were suggested.