Energetic Materials Frontiers (Jun 2021)
Dye-assembled two-dimensional porous HMX for enhanced energy release and safety performance
Abstract
The potential practical applications of high-energy 1,3,5,7-tetranittro-1,3,5,7-tetrazocane (HMX) are hindered by their unfavorable safety behavior and sluggish thermal decomposition. This paper proposes dye-assisted assembly of HMX crystals with crystal violet (CV) as soft templates (denoted as CV-HMX). As revealed by the XPS and molecular-dynamics simulations, preferred electrical interactions between HMX and conjugation electrons in planar CV molecular ensure that the resultant CV-HMX has a two-dimensional (2D) microstructure. The BAM impact sensitivity of CV-HMX is 12.5 J, higher than that of raw-HMX (5 J) and HMX recrystallized from pure water (PW-HMX; 4.5 J). Meanwhile, the BAM friction sensitivity of CV-HMX is 320 N, also much higher than that of PW-HMX (96 N) and raw-HMX (88 N). In addition, the decomposition kinetics of CV-HMX is improved due to its large specific surface area and high pore volume. Such dye-template assembly can be applied to a large number of systems, indicating that the method proposed in this work is universal. This work provides synergistic template regulation on morphology and pore structure using general dye-assisted assembly, holding great promises in developing practically viable high energy materials with favorable sensitivity and improved energy release performance.