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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. 

Abstract Understanding the behavior of confined matter within Van der Waals (VdW) materials is complicated due to the interplay of various factors, including the VdW interaction between the interlayers, the layer interaction with the matter, and the bending strain energy of the layers to accommodate encapsulation. Herein, new insight on the magnitude of pressure and density of water entrapped within confined spaces in VdW materials is provided. This is accomplished by studying the plasmon excitation of water encapsulated between two sheets of graphene membranes in an aberration‐corrected scanning transmission electron microscope. The results indicate ≈12% maximum increase in the density of water under tight graphene encasement, where pressure as high as 400 MPa is expected. The pressure estimation from theoretical analysis considering the effect of VdW forces, Laplace pressure, and strain energy is in agreement with the experimental results. The findings of this work open new opportunities to explore the local physical state of not only water but also other liquid materials under high pressure with imaging and analytical resolutions never achieved before. 

Abstract Imaging materials and biological structures in a liquid environment pose a significant challenge for conventional transmission electron microscopy (TEM) due to stringent requirement of ultrahigh vacuum design in the microscope column. The most recent liquid‐cell TEM technique, graphene liquid‐cell (GLC) microscopy, employs only layers of graphene to encapsulate liquid specimens. Recent efforts with GLC–TEM have demonstrated superior imaging resolution of beam‐sensitive specimens. Herein, the parameters that affect the quality of GLC analysis, including the graphene transfer onto TEM grids, are reviewed. Several important factors that affect the in situ TEM imaging of specimens, including the variations in GLC geometries and capillary pressure are discussed. The interaction between the electron beam and the liquid along with the possibility for artifacts or the formation of radical ions is also highlighted in this review. The scientific discoveries enabled by GLC–TEM in the areas of nucleation and growth of crystals, corrosion, battery science, as well as high‐resolution imaging of organelles and proteins are also briefly discussed. Finally, possible future research directions of GLC–TEM and the associated challenges are discussed. The synergistic effort to accomplish the proposed research directions has the potential to yield new discoveries in both materials and life sciences. 

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. 

Study of nucleation and growth dynamic events of cubic-phase ice crystals at TiO₂–water nanointerface.