Self-encapsulation ultra-soft micro-channel with high thermal conductivity and passive radiation cooling

Oriented towards the industrialization of micro-electronic products, micro-channels suitable for micro and small electronic devices are committed to solving the issue of efficient thermal dissipation in the systems. Accordingly, research on integrating multifunctional thermal management composite materials for designing micro-channels has become a hot development trend. Notably, the design concept of efficient thermal dissipation micro-channel with the dual functional synergy of high thermal conductivity and passive radiation cooling was advanced. The compound of high thermal conductivity hexagonal boron nitride (h-BN) and high-elastic thermoplastic polyurethane (TPU) entrusts the micro-channel with a superb substrate with flexibility, stretchability, hydrophobicity, and high thermal conductivity. Draw support from a zero-energy consumption and environmentally friendly passive radiation cooling strategy, the micro-channel with a polyvinylidene fluoride/cellulose acetate (PVDF/CA) nanofiber film acquires an ultra-high reflectivity of up to 99.50 % (0.2–2.5 μm) and a high emissivity of 94.81 % (8–13 μm). The programmable patterned graphene oxide (GO) ink is assisted with high-viscosity natural Gleditsia sinensis polysaccharide (GSP) through 3D printing. Ultimately, a self-encapsulated, flexible, high thermal conductivity (0.42 W m^-1K⁻¹), passive radiation cooling micro-channel accumulated a temperature difference of 10.76 °C, potentially making a promising thermal management micro-channel system for development.