Plasma-enhanced chemical vapor deposited films on aluminum nanoparticles for enhanced oxidative heat release, extended shelf life, and better dispersion stability

Abstract

This study explores the use of Plasma-Enhanced Chemical Vapor Deposition (PECVD) to apply coatings from six different organic precursors onto aluminum nanoparticles (Al NPs). The goal is to improve their energetic performance, extend their shelf life, and enhance their dispersion stability in non-polar solvents. The coatings were analyzed using various characterization techniques, including Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), and Fourier-transform Infrared Spectroscopy (FTIR). Thermal analysis (TGA/DSC) was used to measure oxidative heat release and assess shelf-life stability over 12 months, while Dynamic Light Scattering (DLS) was used to evaluate dispersion in dodecane. The results indicate that plasma films derived from perfluorodecalin (PFD) and oleic acid (OA) significantly increased the oxidative heat release by 13.33% and 30%, respectively, after doing PECVD for 30 min. After 12 months of storage, these coatings still showed enhanced heat release of 7% and 20%. Toluene-based plasma coatings demonstrated the best passivation capability over the 12-month period. Furthermore, the PFD and OA coatings also provided excellent dispersion stability, reducing the aggregation of Al NPs in dodecane. The study suggests that creating sandwich coatings, combining fluorocarbon (CF_x) and plasma-reacted Toluene, could be a promising direction for future research to optimize energy performance, shelf life, and dispersion stability in metal nanoparticles.