With the rapid development of two-phase heat exchangers, the further improvement of the capillary performance of their internal wick faces a great challenge. As an important technology in the surface treatment of aluminum alloys, anodic oxidation has been widely used to develop various functional nanostructures. In this study, nanopores with diameters of 30–40 nm were fabricated on the surface of aluminum fibers through anodic oxidation under an oxalic acid system. Results showed that anodizing increased the specific surface area of the aluminum braid by 163 times, and changed its surface wettability from hydrophobic to superhydrophilic. A significant reduction in the effective capillary radius can substantially increase the capillary force of aluminum braids on the basis of capillary theory. Therefore, the nanoporous aluminum braids can be used as a novel wick in the vapor chamber to improve its capillary performance. Capillary rate-of-rise tests with ethanol and acetone were performed to characterize the capillary of this novel wick structure. Infrared thermal imaging was utilized to monitor the capillary rise of aluminum braided wicks. The capillary force of the anodized wicks was greater than that of a normal wick, and the maximum capillary rise height was 81 mm. The nanoporous aluminum braided wicks prepared by anodizing could be applied in heat transfer.

The design of flexible wearable electronic devices that can shield electromagnetic waves and work in all weather conditions remains a challenge. We present in this work a low-cost technology to prepare an ultra-thin carbon fabric–graphene (CFG) composite film with outstanding electromagnetic interference shielding effectiveness (EMI SE) and electro-photo-thermal effect. The compatibility between flexible carbon fabric skeleton and brittle pure graphene matrix empowers this CFG film with adequate flexibility. The reticular fibers and porous structures play a vital role in multiple scattering and absorption of electromagnetic waves. In the frequency range of 30–1500 MHz, the CFG film can achieve a significantly high EMI SE of about 46 dB at tiny thickness (0.182 mm) and density (1.4 g cm−3) predominantly by absorption. At low safe voltages or only in sunlight, the film can self-heat to its saturation value rapidly in 40 s. Once the electricity or light supply is stopped, it can quickly dissipate heat in tens of seconds. A combination of the EMI SE and the prominent electro-photo-thermal effect further enables such a remarkable EMI shielding film to have more potential applications for communication devices in extreme zones.

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