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In this research, molecular dynamic (MD) simulations computation is applied to generally study the coating behavior of palmitic acid molecules and aluminum (Al) nanoparticle (ANP) surface through single and multi-molecule models. Changes and comparisons of adsorption distance, energy, effectiveness and stability are generally discussed in this study. Those obtained results indicate that the adsorption configuration of palmitic acid and Al has shown the adsorption polarity clearly. For carboxyl terminal of palmitic acid and Al surface, when their critical adsorption angle is around 60∘, its distance is within 9 Å. Besides, the decisive atomic group of palmitic acid molecule is carboxyl, whose oxygen atom with double bond can adsorb the Al atom stably. This adsorption effect and formation is close to the covalent bond. During the adsorption process, van der Waals force acts on the long-distance attraction, and the Coulomb force acts more critically as the short-range adsorption force. Finally, the gas coating has proper advantages over the liquid coating, as the erosion of Al surface is much lower when it is surrounded by gas-phased palmitic acid.

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In this study, novel carbon nanotube (CNT) and transition-metal oxides (TMOs) nanoparticle catalysts were prepared and their effects on the thermal decomposition of potassium perchlorate (KP) were investigated. Nanocatalysts have been widely studied because of their excellent properties, such as the high surface energies of nanoparticles and their ease of agglomeration adversely affect their catalytic performances. Good dispersion is the key to good nanocatalytic activity. The composite catalysts were prepared by loading a nanocatalyst on CNTs; this improves nanoparticle dispersion, promotes electron transfer during the reaction, and increases the catalytic effect. Different types of CNT-based composite catalysts and their corresponding single nanocatalysts were each added to KP. The effects of the catalysts on the thermal decomposition of KP were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The activity of each catalyst was evaluated on the basis of the changes in the thermal decomposition peaks and the apparent decomposition heats. The results show that the activity of a composite catalyst in KP thermal decomposition is much higher than that of its corresponding single nanocatalyst.

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