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Abstract Emulsions are widely used in many industrial applications, and the development of efficient techniques for synthesizing them is a subject of ongoing research. Vapor condensation is a promising method for energy‐efficient, high‐throughput production of monodisperse nanoscale emulsions. However, previous studies using this technique are limited to producing small volumes of water‐in‐oil dispersions. In this work, a new method for the continuous synthesis of nanoscale emulsions (water‐in‐oil and oil‐in‐water) is presented by condensing vapor on free‐flowing surfactant solutions. The viability of oil vaporization and condensation is demonstrated under mild heating/cooling using diverse esters, terpenes, aromatic hydrocarbons, and alkanes. By systematically investigating water vapor and oil vapor condensation dynamics on bulk liquid‐surfactant solutions, a rich diversity of outcomes, including floating films, nanoscale drops, and hexagonally packed microdrops is uncovered. It is demonstrated that surfactant concentration impacts oil spreading, self‐emulsification, and such behavior can aid in the emulsification of condensed oil drops. This work represents a critical step toward advancing the vapor condensation method's applications for emulsions and colloidal systems, with broad implications for various fields and the development of new emulsion‐based products and industrial processes. 

Abstract Synthetic surfaces engineered to regulate phase transitions of matter and exercise control over its undesired accrual (liquid or solid) play a pivotal role in diverse industrial applications. Over the years, the design of repellant surfaces has transitioned from solely modifying the surface texture and chemistry to identifying novel material systems. In this study, selection criteria are established to identify bio‐friendly phase change materials (PCMs) from an extensive library of vegetable‐based/organic/essential oils that can thermally respond by harnessing the latent heat released during condensation and thereby delaying ice/frost formation in the very frigid ambient that is detrimental to its functionality. Concurrently, a comprehensive investigation is conducted to elucidate the relation between microscale heat transport phenomena during condensation and the resulting macroscopic effects (e.g., delayed droplet freezing) on various solidified PCMs as a function of their inherent thermo‐mechanical properties. In addition, to freeze protection, many properties that are responsive to the thermal reflex of the surface, such as the ability to dynamically tune optical transparency, moisture harvesting, ice shedding, and quick in‐field repairability, are achievable, resulting in the development of protective coatings capable of spanning a wide range of functionalities and thereby having a distinctive edge over conventional solutions. 

Abstract Anti‐icing and icephobic materials play a crucial role in demanding applications ranging from energy to transportation systems operating in frigid climates. Despite remarkable advancements in the development of such surface coatings, the use of anti/de‐icing chemicals remains one of the go‐to solutions for ice management. However, they are notoriously prone to removal by shear forces and dissolution. Herein, the design rationale for developing a family of cryoprotectant and phase‐change material (PCM)‐based compositions in the form of mixtures, non‐aqueous emulsions‐creams, and gels that can substantially overcome such challenges is reported. This is achieved through the sustenance of an in‐situ‐generated surface hydration layer that protects the underlying substrate from a variety of foulants, varying from ice to disease‐causing bacteria. Each formulation utilizes unique chemistry to curtail the embodied cryoprotectant loss and can be easily applied as an all‐in‐one sprayable/paintable coating capable of significantly outperforming untreated industrial materials in terms of their ability to delay condensation‐frosting and shed ice simultaneously. Concomitantly, an array of formulation‐specific functionalities is observed in the family, which includes optical transparency, mechanical durability, high shear‐flow stability, and self‐healing characteristics. 

Impurities in water affect ice adhesion strength on surfaces. Depending on the freezing rate, they can be trapped in ice or pushed out, forming a lubricating layer. They also affect the quasi-liquid layer between ice and surface, impacting adhesion.