Zhang Hongqiang, Zhao Guanlei, Wu Shuwang, Alsaid Yousif, Zhao Wenzheng, Yan Xiao, Liu Lei, Zou Guisheng, Lv Jianyong, He Ximin, He Zhiyuan, Wang Jianjun
School of Mechanical Engineering and Automation, Beihang University, 100191 Beijing, China.
Institute of Chemistry, University of Chinese Academy of Sciences, 100190 Beijing, China.
Proc Natl Acad Sci U S A. 2021 May 4;118(18). doi: 10.1073/pnas.2100978118.
The inhibition of condensation freezing under extreme conditions (i.e., ultra-low temperature and high humidity) remains a daunting challenge in the field of anti-icing. As water vapor easily condensates or desublimates and melted water refreezes instantly, these cause significant performance decrease of most anti-icing surfaces at such extreme conditions. Herein, inspired by wheat leaves, an effective condensate self-removing solar anti-icing/frosting surface (CR-SAS) is fabricated using ultrafast pulsed laser deposition technology, which exhibits synergistic effects of enhanced condensate self-removal and efficient solar anti-icing. The superblack CR-SAS displays superior anti-reflection and photothermal conversion performance, benefiting from the light trapping effect in the micro/nano hierarchical structures and the thermoplasmonic effect of the iron oxide nanoparticles. Meanwhile, the CR-SAS displays superhydrophobicity to condensed water, which can be instantly shed off from the surface before freezing through self-propelled droplet jumping, thus leading to a continuously refreshed dry area available for sunlight absorption and photothermal conversion. Under one-sun illumination, the CR-SAS can be maintained ice free even under an ambient environment of -50 °C ultra-low temperature and extremely high humidity (ice supersaturation degree of ∼260). The excellent environmental versatility, mechanical durability, and material adaptability make CR-SAS a promising anti-icing candidate for broad practical applications even in harsh environments.
在极端条件下(即超低温和高湿度)抑制凝结冻结在防冰领域仍然是一项艰巨的挑战。由于水蒸气容易凝结或凝华,且融化的水会立即重新冻结,这些都会导致大多数防冰表面在这种极端条件下性能显著下降。在此,受小麦叶片启发,采用超快脉冲激光沉积技术制备了一种有效的冷凝水自去除太阳能防冰/防霜表面(CR-SAS),该表面具有增强的冷凝水自去除和高效太阳能防冰的协同效应。超黑的CR-SAS表现出优异的抗反射和光热转换性能,这得益于微/纳分级结构中的光捕获效应和氧化铁纳米颗粒的热等离子体效应。同时,CR-SAS对冷凝水表现出超疏水性,在冻结前冷凝水可通过自驱动液滴跳跃立即从表面脱落,从而形成一个可不断更新的干燥区域,用于吸收阳光和进行光热转换。在一个太阳光照下,即使在-50°C的超低温和极高湿度(冰过饱和度约为260)的环境中,CR-SAS也能保持不结冰。其出色的环境适应性、机械耐久性和材料适应性使CR-SAS成为即使在恶劣环境下也具有广泛实际应用前景的防冰候选材料。