Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, Nanjing 211189, P. R. China.
School of Energy and Environment, Southeast University, Nanjing 210096, P. R. China.
Sci Rep. 2017 Jan 11;7:40300. doi: 10.1038/srep40300.
Spontaneous movement of condensed matter provides a new insight to efficiently improve condensation heat transfer on superhydrophobic surface. However, very few reports have shown the jumping behaviors on the sprayable superhydrophobic coatings. Here, we developed a sprayable silica nano-porous coating assembled by fluorinated nano-chains to survey the condensates' dynamics. The dewdrops were continuously removed by self- and/or trigger-propelling motion due to abundant nano-pores from random multilayer stacking of nano-chains. In comparison, the dewdrops just could be slipped under the gravity effect on lack of nano-pores coatings stacked by silica nano-spheres and nano-aggregates. More interestingly, the spontaneous jumping effect also occurred on micro-scale frost crystals under the defrosting process on nano-chains coating surfaces. Different from self-jumping of dewdrops motion, the propelling force of frost crystals were provided by a sudden increase of the pressure under the frost crystal.
凝聚态物质的自发运动为有效地提高超疏水表面的冷凝传热提供了新的见解。然而，很少有报道显示喷雾超疏水涂层上的跳跃行为。在这里，我们开发了一种由氟纳米链组装的喷雾纳米多孔二氧化硅涂层来研究冷凝物的动力学。由于纳米链的随机多层堆积形成丰富的纳米孔，液滴会通过自驱动和/或触发驱动的方式不断被除去。相比之下，在缺乏纳米孔的情况下，液滴只能在重力作用下在由纳米球和纳米聚集体堆积而成的涂层上滑落。更有趣的是，在纳米链涂层表面的除冰过程中，微尺度的霜晶也会发生自发跳跃效应。与液滴运动的自跳跃不同，霜晶的推进力是由霜晶下压力的突然增加提供的。
