Pb Single Atoms Enable Unprecedented Catalytic Behavior for the Combustion of Energetic Materials.

Manipulating the thermal decomposition behavior of energetic materials is the key to further pushing the combustion performance of solid rocket propellants. Herein, atomically dispersed Pb single atoms on polydopamine (PDA-Pb) are demonstrated, which display unprecedented catalytic activity toward the thermal decomposition of cyclotrimethylenetrinitramine (RDX). Impressively, RDX-based propellants with the addition of PDA-Pb catalyst exhibit substantially enhanced burning rates (14.98 mm s-1 at 2 MPa), which is 4.8 times faster than that without PDA-Pb and represents the best catalytic performance among Pb-based catalysts. Moreover, it also possesses low-pressure exponents in broad pressure ranges, which can enable more stable and safer combustion in solid rocket engines. Theoretical calculation unravels the efficient catalytic activity is stemmed from the enhanced interfacial electronic coupling between RDX and PDA-Pb via orbital level engineering. More importantly, PDA-Pb also presents similar catalytic behavior toward the decomposition of nitrocellulose, suggesting its broad catalytic generality. This work can open up new opportunities in the field of energetic compound combustion by exploring Pb-based single atom catalysts and beyond.