Femtosecond Laser Achieving High‐Entropy Alloys Composited Multiscale Structures Toward Efficient Crude Oil Transport

Crude oil becomes highly viscous and may solidify at low temperatures, reducing pipeline throughput and increasing transport energy demand. Conventional heating systems require complex infrastructure and substantial energy input, limiting their use in low-energy, high-performance oil transport. Here, we report a flash femtosecond laser route that creates an in situ photothermal superhydrophobic high-entropy alloy nanoparticle (HEA-NPs)/aluminum surface for solar-assisted crude oil transport. The transient heating and quenching generated by the laser produce FeCoNiCrMnLa HEA-NPs and distribute them uniformly across the hierarchical aluminum substrate (HEAs/PA). After vacuum annealing of HEAs/PA, the resulting multiscale structures (HEAs/MS) surface contains a microscale pyramid array structure, nanoscale porous coral reef structure, and HEA-NPs, providing strong photothermal conversion and superhydrophobicity. It exhibits an average absorptance of ∼96.6% across the visible and near-infrared regions and reaches ∼71.9°C under 1 sun, while its water contact angle (WCA) is ∼155.4° and remains stable after multiple durability tests. As a transport pipe, HEAs/MS reduces crude oil viscosity and delivers a flow rate up to 4 times that of pristine aluminum under 1 sun. This work offers a convenient method for synthesizing metal-based high-entropy alloy nanoparticles and also provides a low-energy strategy for crude oil transport.