Novel high-performance endothermic fuels from quasi-homogeneous nano-engineering

Endothermic hydrocarbon fuels (EHFs) with high heat sink have revolutionized the thermal management technology of hypersonic aircraft over the past decades. In this work, highly stable quasi-homogeneous systems as a novel type of potential EHFs are introduced by dispersing water-rich multifunctional nanospheres in hydrocarbons. Studies conducted using cryo-transmission electron microscopy, dynamic light scattering and small-angle X-ray scattering have demonstrated that nanospheres with diameter less than 100 nm can be solubilized into hydrocarbons to form semi-transparent systems. They resist phase separation, remain stable under extreme centrifugal forces (exceeding 8000 RCF), and have low freezing points (subcooling temperature below −40 °C). In these quasi-homogeneous systems, the amphiphilic macromolecules within the multifunctional nanospheres serve dual roles: they stabilize the nanospheres and initiate the thermal cracking of the fuel, while the water component mitigates coking tendencies and contributes to the high heat sink. Ultimately, this novel fuel can achieve up to 19 % improvement in heat sink (from 3.42 MJ·kg −1 to 4.05 MJ·kg −1 at 3.5 MPa) and a 96.8 % reduction in coke formation (at 700 °C) with only a 9 % loss in volumetric heat value, without the need of catalysts.