Enhanced reactivity of nanoenergetic materials: A first-principles molecular dynamics study based on divide-and-conquer density functional theory

Integration of nanowires and nanoparticles of energetic materials into semiconducting structures is giving birth to nanoenergetics-on-a-chip technology. Understanding and controlling the reactions of nanoenergetic materials pose a theoretical challenge for combining quantum-mechanical accuracy with large scales to capture nanostructural effects. Recent developments in linear-scaling density functional theory have set a stage for first-principles molecular dynamics simulation of thermite reaction at an Al/Fe2O3 interface. Here, we report the finding of a concerted metal-oxygen flip mechanism that enhances mass diffusion and reaction rate at the interface. This mechanism leads to two-stage reactions, which may explain recent experimental observation in thermite nanowire arrays.