Molecular pulleys have been designed and fabricated to mitigate ice accretion.

Despite the remarkable advances in mitigating ice formation and accretion, however, no engineered anti-icing surfaces today can durably prevent frost formation, droplet freezing, and ice accretion in an economical and ecofriendly way. Herein, sustainable and low-cost electrolyte hydrogel (EH) surfaces are developed by infusing salted water into a hydrogel matrix for avoiding icing. The EH surfaces can both prevent ice/frost formation for an extremely long time and reduce ice adhesion strength to ultralow value (Pa-level) at a tunable temperature window down to −48.4 °C. Furthermore, ice can self-remove from the tilted EH surface within 10 s at −10 °C by self-gravity. As demonstrated by both molecular dynamic simulations and experiments, these extreme performances are attributed to the diffusion of ions to the interface between EH and ice. The sustainable anti-icing properties of EH can be maintained by replenishing in real-time with available ion sources, indicating the promising applications in offshore platforms and ships.

Ice accretion is a severe challenge for both production and livelihood in cold regions. Previously reported high-performance icephobic surfaces by infusing lubricants are either temporarily icephobic, chemically unstable, or mechanically weak. Herein, we report the design and fabrication of submicrometer porous polydimethylsiloxane (PDMS; Sylgard 184 with weight ratio 10:1) foam based chemically stable and mechanically robust icephobic materials. The relationship between the ice adhesion strength and porosity is revealed. Without any surface additives and lubricants as well as sacrificing the cross-linking density of elastomeric foam, the stable ice adhesion strength of the submicrometer porous foam reaches 16.8 ± 5.8 kPa after 50 icing/deicing cycles. In addition, the icephobic foams show excellent chemical stability and mechanical robustness, and the ice adhesion strengths are all less than 30.0 kPa after acid/base/salt/organic solvent corrosion and 1000 abrasion cycles. The submicrometer porous elastomeric strategy opens up a new avenue for high-performance durable icephobic materials with excellent stability and robustness.

Broadband high transmittance, humidity resistance and mechanical robustness are three important aspects that dictate the practical applications of antireflective thin films.

Clathrate hydrates show wide applications in energy recovery and storage, CO2 capture and storage, and other sustainable technologies. Water vacancy in clathrate hydrates is a common defect; however, its effects on the mechanical properties of clathrate hydrates, especially CO2 hydrates, have not been well studied. Herein, the mechanical characteristics of CO2 hydrates with three different types of water vacancy defects are investigated for the first time through molecular dynamics simulations with several popular water force fields. It turns out that the mechanical properties of CO2 clathrate hydrate vary with the type of water vacancy and water force field. Upon critical strains, a variety of unconventional cages of 425862, 425863, 425864, 4151062, 4151063, and 4151064 form, of which 4151062 predominates and is identified to be transient and a clathrate intermediate in forming 425862, 425863, and 425864. Moreover, diverse cage transformations of 51262 ↔ 4151063, ↔ 4151062, ↔ 425863, ↔ 425864 and 512 ↔ 4151062, ↔ 425862 occur via two distinct transformation mechanisms including insertion/removal and rotation of a pair of water molecules. This study provides new perspectives on the mechanics and microstructural transformations of CO2 hydrate, which are crucial for evaluating the formation and mechanical stability of CO2 hydrate-bearing sediments as well as the CO2 geological storage by hydrate-based technologies.