Understanding the mechanism of ice adhesion on surfaces is crucial for anti-icing surfaces, and it is not clear if superhydrophobic surfaces could reduce ice adhesion. Here, we investigate ice adhesion on model surfaces with different wettabilities. The results show that the superhydrophobic surface cannot reduce the ice adhesion, and the ice adhesion strength on the superhydrophilic surface and the superhydrophobic one is almost the same. This can be rationalized by the mechanical interlocking between the ice and the surface texture. Moreover, we find that the ice adhesion strength increases linearly with the area fraction of air in contact with liquid.

Understanding the role played by solid surfaces in ice nucleation is a significant step toward designing anti-icing surfaces. However, the uncontrollable impurities in water and surface heterogeneities remain a great challenge for elucidating the effects of surfaces on ice nucleation. Via a designed process of evaporation, condensation, and subsequent ice formation in a closed cell, we investigate the ice nucleation of ensembles of condensed water microdroplets on flat, solid surfaces with completely different wettabilities. The water microdroplets formed on flat, solid surfaces by an evaporation and condensation process exclude the uncontrollable impurities in water, and the effects of surface heterogeneities can be minimized through studying the freezing of ensembles of separate and independent water microdroplets. It is found that the normalized surface ice nucleation rate on a hydrophilic surface is about 1 order of magnitude lower than that on a hydrophobic surface. This is ascribed to the difference in the viscosity of interfacial water and the surface roughness.

Supercharged unfolded polypeptides (SUPs) are exploited for controlling ice nucleation via tuning the nature of charge and charge density of SUPs. The results show that positively charged SUPs facilitate ice nucleation, while negatively charged ones suppress it. Moreover, the charge density of the SUP backbone is another parameter to control it.

A series of surfaces with the similar morphology but different surface free energy were fabricated to achieve surfaces with distinct condensation modes. It was found that the freezing of condensed water formed via filmwise condensation occurred much more quickly and at a higher temperature than that of condensed water formed via dropwise condensation.

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In this work, high-performance solar-blind photodetectors based on MXenes–β-Ga2O3 Schottky junctions have been developed by utilizing transparent conductive MXenes as the Schottky electrode of β-Ga2O3. Due to the high MXenes–β-Ga2O3 Schottky barrier, the photodetectors exhibit a rectification ratio as high as over 103 at ±2 V. At zero bias, the photodiodes show a responsivity of 12.2 mA W−1 at 248 nm and a detectivity of 6.1 × 1012 Jones, which are among the best values for β-Ga2O3-based solar-blind photodetectors working at zero bias. In addition, the Schottky photodiodes show a fast response speed with a rise time of 8 μs and decay time of 131 μs. Our results indicate that MXenes may be promising candidate for use as transparent conductive electrodes for UV optoelectronics.

A versatile, convenient, and cost-effective method that can be used for grafting anti-icing materials onto different surfaces is highly desirable. Based on mussel-inspired chemistry, the anti-icing coating with extremely low ice adhesion is enabled by constructing a self-sustainable lubricating layer, achieved via modifying solid substrates with a highly hydrophilic conjugate of poly(acrylic acid)–dopamine. Both unfreezable and freezable water remain liquidlike at subzero conditions and synergistically fulfill the role of lubrication for reducing the ice adhesion. The anti-icing coatings show excellent stability in harsh environments and durability after the cross-linking. More importantly, this coating can be applied to various substrates and is of great promise for practical applications.

We designed 12-amino acid peptides as antifreeze protein (AFP) mimetics and tuned the antifreeze activity of the peptides by their structures. Moreover, these short peptides were first immobilized to surfaces as an anti-icing coating. We discovered that the peptides with higher antifreeze activity exhibited better anti-icing performance. It is the first time that short peptides were successfully applied to fabricate anti-icing surfaces, which is certainly advantageous in comparison to the AFP anti-icing coatings previously reported.