Enhanced heat transfer of ultrathin heat pipes enabled by Crassula muscosa-inspired structures

With the rapid iteration of electronic devices toward higher integration and miniaturization, the heat flux of their core components has risen drastically. Ultrathin heat pipes undesirably suffer from a limited heat transfer efficiency owing to structural characteristics of wicks, unable to meet the requirement for high-efficiency heat dissipation. To this end, in this study, we develop a biomimetic nanostructured reentrant channel based ultrathin heat pipe by coupling Crassula muscosa inspired liquid diode microstructures with superhydrophilic nanostructures together. Compared with conventional ultrathin heat pipes with parallel channel wicks, the heat transfer performances of our ultrathin heat pipes are greatly enhanced as manifested by a maximum 81.5% improvement of effective thermal conductivity reaching up to 1851.3 W m −1 K −1 and a maximum 44.9% reduction of thermal resistance approaching 13.4 K/W. We further investigate the role of liquid filling ratio and bionic reentrant microstructures in the regulation of heat transfer performance, and demonstrate superior anti-gravity performance in extreme conditions. Moreover, the BNRC-UHP maintains stable heat transfer performance during 50-h continuous operation and after 50 heating-cooling cycles, demonstrating excellent long-term stability and cycling reliability. Through combined coupling of bionic structural design and nanointerface engineering, this study provides an effective technical approach for the structural innovation and performance optimization of ultrathin heat pipes, which brings broad application prospects in the field of thermal management for microelectronic devices.