Femtoliter droplets at solid interfaces attract significant interest as the basic units in many physical and biological processes. One challenge in the application of these tiny droplets is their fast evaporation rate in air due to their large surface‐to‐volume ratio. Ionic liquids with low volatility present an opportunity to overcome this challenge. The advanced properties of ionic liquids (ILs) have enabled them to be widely applied in chemical reactions, biopolymers, molecular self‐assembly and separations. At interfaces, the wettability of ILs is pursued in next‐generation lubricants and battery technology. Previously, IL droplets at solid surfaces have been prepared by nanodispensing, micropipette, and solvent evaporation. Here, the solvent exchange protocol is extended to yield protic ionic liquid droplets at the interface with controlled size, distribution, location, and stability in both liquid and air surroundings. During growth, the droplets demonstrate an interesting dewetting dynamic. This behavior has not been observed for molecular liquids during solvent exchange and suggests interesting interfacial dynamics of the ionic liquid. One proof‐of‐concept application of using surface nanodroplets of the protic ionic liquid ethylammonium nitrate for compartmentalized reactions and templating SiO₂ nanostructures is demonstrated. This work broadens and intertwines the opportunities of ILs and nanodroplets.

中文翻译：

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用于纳米加工的表面质子离子液体纳米液滴的形成

作为许多物理和生物过程中的基本单位，在固体界面处的飞升液滴引起了人们极大的兴趣。这些微小液滴的应用面临的一个挑战是由于其大的表面体积比，它们在空气中的快速蒸发速率。低挥发性离子液体为克服这一挑战提供了机会。离子液体（ILs）的先进性能使其能够广泛应用于化学反应，生物聚合物，分子自组装和分离。在界面上，下一代润滑剂和电池技术追求离子液体的润湿性。以前，已经通过纳米分配，微量移液器和溶剂蒸发来制备固体表面的IL液滴。这里，扩展了溶剂交换方案，以在界面处产生质子离子液滴，并在液体和空气环境中控制了大小，分布，位置和稳定性。在生长过程中，液滴表现出有趣的去湿动态。在溶剂交换过程中尚未观察到分子液体的这种行为，并暗示了离子液体的有趣的界面动力学。使用质子离子液体硝酸乙基铵硝酸盐的表面纳米液滴进行间隔反应和模板化SiO的一种概念验证应用 在溶剂交换过程中尚未观察到分子液体的这种行为，并暗示了离子液体的有趣的界面动力学。使用质子离子液体硝酸乙基铵硝酸盐的表面纳米液滴进行间隔反应和模板化SiO的一种概念验证应用 在溶剂交换过程中尚未观察到分子液体的这种行为，并暗示了离子液体的有趣的界面动力学。使用质子离子液体硝酸乙基铵硝酸盐的表面纳米液滴进行间隔反应和模板化SiO的一种概念验证应用展示了_2种纳米结构。这项工作拓宽并交织了IL和纳米液滴的机会。