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With the rapid development of high-performance electronics in aerospace, communication, and energy storage systems, the huge heat flux poses an increasing threat to the safety of electronic devices. In contrast to conventional external cooling strategies, on-chip heat dissipation with targeted directional regulation emerges as a promising solution for extreme thermal conditions induced by thermal shock and elevated heat flux. Differing from the existing cooling devices that depend on the temperature gradient, this thermal diode can realize the predetermined unidirectional heat transfer with a low thermal resistance by modulating the fluid flow resistance, effectively preventing heat reflux and the consequent overheating of electronic components. The correlation between flow performance and heat transfer efficacy has been analyzed. When the temperature of the condenser surpasses that of the evaporator, heat transfer in the reverse direction is inhibited, safeguarding electronic components from overheating. Experimental results reveal that the thermal diode exhibits a remarkable thermal dipolarity of 4.05, coupled with a flow dipolarity of 21, ensuring resilience against severe thermal shock in extreme environments. The proposed heat dissipation strategy offers valuable insights for the design of directional heat dissipation devices tailored to meet the extreme thermal management demands of modern electronics. [ABSTRACT FROM AUTHOR]

Directional liquid transport has broad engineering applications, and recent efforts have demonstrated the feasibility of rapid and long-distance directional transport using external driving forces, such as light, electricity, magnetism, and mechanical force. However, the externally driven mechanism limits its application in small and intelligent areas. The manufacture of the passive directional flow surfaces remains a significant challenge. In this account, we present a passive microfluidic chip with microwedge grooved channels for improved fluid directional manipulation. Benefiting from the cooperative effect of the asymmetric resistance and capillary driving force, the microwedged channel possesses the reliable functions for long-distance, anti-gravity, and continuous directional fluid transport in a microfluidic chip. To improve these properties, we optimized the structure parameters of the microwedges, resulting in a unidirectional value of up to 7.48. Furthermore, we explored the functions and applications of these microwedge arrays in intelligent and microfluidic systems. By combining different microwedge arrays, we programed that the microfluidic chips were programed with different functions, such as microfluidic logic, liquid gating, and anti-gravity capabilities, with multi-path transportation of an overall length of 537.6 mm. This research provides important guidance on functional surfaces for the design of intelligent integrated microfluidic chips and plays a significant role in promoting practical industrial applications. [ABSTRACT FROM AUTHOR]