Tuning the Reactivity of Perfluoropolyether-Functionalized Aluminum Nanoparticles by the Reaction Interface Fuel-Oxidizer Ratio

Nanomaterials (Basel). 2022 Feb 3;12(3):530. doi: 10.3390/nano12030530.

Abstract

To deepen the oxidation depth and promote the exothermic reaction of aluminum nanoparticles (Al NPs), this work constructed perfluoropolyether-functionalized Al NPs by using a facile fabrication method. It was determined that perfluoropolyether (PFPE) was uniformly distributed on the surface of the Al NPs with no obvious agglomeration by micro-structure analysis. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), microcomputer automatic calorimeter (MAC), and combustion and ignition experiments were performed for varying percentages of PFPE blended with Al NPs to examine the reaction kinetics and combustion performance. It was revealed that the oxidation mechanism of PFPE-functionalized Al NPs at a slow heating rate was regulated by the reaction interface Fuel-Oxidizer ratio. Due to the enlarged Fuel-Oxidizer contact surface area, fluorine atoms could adequately decompose the inert alumina shell surrounding the Al NPs, optimizing the combustion process of Al NPs. The analytical X-ray diffraction (XRD) pattern results confirmed the existence of aluminum trifluoride in combustion products, providing insights into the oxidation mechanism of Al NPs. The obtained results indicated that PFPE participated in the oxidation of Al NPs and improved the overall reactivity of Al NPs.

Keywords: Al NPs; oxidation mechanism; perfluoropolyether-functionalized; reaction interface Fuel-Oxidizer ratio.