Hydrophobic oil droplets, particles, and air bubbles can be dispersed in water as kinetically stabilized dispersions. It has been established since the 19th century that such objects harbor a negative electrostatic potential roughly twice larger than the thermal energy. The source of this charge continues to be one of the core observations in relation to hydrophobicity, and its molecular explanation is still debated. What is clear though is that the stabilizing interaction in these systems is understood in terms of electrostatic repulsion via Derjaguin, Landau, Verwey, and Overbeek theory. Recent work [A. P. Carpenter et al., Proc. Natl. Acad. Sci. U. S. A. 116, 9214 (2019)] has added another element into the discussion, reporting the creation of bare near-zero charged droplets of oil in neat water that are stable for several days. Key to the creation of the droplets is a rigorous glassware cleaning procedure. Here, we investigate these conclusions and show that the cleaning procedure of glassware has no influence on the electrophoretic mobility of the droplets and that oil droplets with near-zero charge are unstable. We provide an alternative possible explanation for the observations involving glass surface chemistry.

中文翻译：

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裸油纳米液滴在水中的稳定性和必要的电泳迁移率。

疏水性油滴，颗粒和气泡可作为动力学稳定的分散体分散在水中。自19世纪以来，已经确定此类物体具有负的静电势，大约是热能的两倍。这种电荷的来源仍然是与疏水性有关的核心观察之一，其分子解释仍在争论中。不过，很清楚的是，通过Derjaguin，Landau，Verwey和Overbeek理论，通过静电排斥可以理解这些系统中的稳定相互作用。最近的工作[AP Carpenter等。，过程。Natl。学院 科学 美国116，9214（2019）]在讨论中增加了另一个要素，报告了在纯净水中可稳定形成几天的几乎零电荷的裸露油滴的产生。产生液滴的关键是严格的玻璃器皿清洁程序。在这里，我们调查这些结论，并表明玻璃器皿的清洁过程对液滴的电泳迁移率没有影响，并且带近零电荷的油滴是不稳定的。对于涉及玻璃表面化学的观察，我们提供了另一种可能的解释。