CuI-Filled Single-Walled Carbon Nanotubes: Efficient Catalysts for Thermal Decomposition, Ignition, and Combustion of CL-20

CL-20 is used to replace conventional oxidizers in propellants to boost the energy signature. Laser technology is an important means of propellant ignition and combustion enhancement. Improving ignition and combustion performance is of great significance for a wide range of propellant applications. Here, a novel CuI structure encapsulated in a single-walled carbon nanotube network (CuI@SWCNT), with excellent reactivity, electrical conductivity, thermal conductivity, and photothermal conversion, was used as a combustion catalyst. The network’s superb electrical conductivity and large specific surface area provide a convenient transport channel for electrons to the center of catalytic activity. The effects of CuI, SWCNT, and CuI@SWCNT on the thermal decomposition, ignition, and combustion properties of CL-20 were investigated in detail by differential scanning calorimetry (DSC), thermogravimetric-infrared (TG-IR), laser ignition, burning rate experiment, and condensed combustion products collection. As a combustion catalyst, CuI@SWCNT exploits the synergistic properties of CuI and SWCNT. It has the effect of enhancing the thermal decomposition performance (T_p advanced by 7.5 °C, E_a reduced by 35.0%), shortening the ignition delay time (reduced by 92.2%), increasing the burning rate (enhanced by 75.9%) and improving the combustion efficiency of CL-20. It also optimizes the poor self-sustaining combustion performance of CL-20. This work provides a new combustion catalyst strategy for comprehensively enhancing the thermal decomposition, ignition, and combustion performance of CL-20 and provides insight into its impact mechanisms.