Cassie's Law Reformulated: Composite Surfaces from Superspreading to Superhydrophobic

Research Progress of Photothermal Superhydrophobic Surfaces for Anti-Icing/Deicing

Photothermal superhydrophobic surfaces with micro/nano-structured morphologies have emerged as promising candidates for anti-icing and deicing applications due to their exceptional water repellency and efficient solar-to-thermal conversion. These surfaces synergistically integrate the passive icephobicity of superhydrophobic coatings with the active heating capability of photothermal materials, offering energy-efficient and environmentally friendly solutions for sectors such as aviation, wind energy, and transportation. Hence, they have received widespread attention in recent years. This review provides a comprehensive overview of recent advances in photothermal superhydrophobic coatings, focusing on their anti-icing/deicing mechanisms, surface wettability, and photothermal conversion performance for anti-icing/deicing applications. Special emphasis is placed on material categories, including metals and their compounds, carbon-based materials, and polymers, analyzing their structural features and application effectiveness. Furthermore, the application of anti-icing/deicing in various fields is described. Finally, perspectives on future development are presented, including pursuing fluorine-free, cost-effective, and multifunctional coatings to meet the growing demand for innovative, sustainable anti-icing/deicing technologies.

Preparation and characterization of chitosan film modified with polydimethylsiloxane capped by mono-terminal epoxy groups

The development of degradable food packaging materials with hydrophobic and oleophobic properties is a key to focus in reducing plastic waste. Chitosan is gaining interest for its versatility and easy modification, but its application is limited by the poor hydrophobicity and oleophobicity. Using polymers to modify chitosan films has been shown as a promising approach to solve this issue. In this study, the modified films (CS/xmono-PDMS-E, where x = 0.25, 0.5, 1, 2, and 3 %) were prepared by utilizing mono-terminal epoxy-terminated polysiloxane (mono-PDMS) and chitosan (CS) through chemical grafting. The qualities of these films were characterized. CS/xmono-PDMS-E films were demonstrated to have enhanced hydrophobicity, oleophobicity, moisture resistance, and thermal stability in comparison to CS films. Furthermore, because SiOSi has a greater bonding energy in the PDMS chain segment, the CS/xmono-PDMS-E films showed superior UV shielding. The resistance to weathering of CS/xmono-PDMS-E films was also greatly enhanced by the low surface energy of PDMS, which moved to the surface during drying. By combining experimental design with result characterization, this work provides a new strategy for bio-based packaging materials featuring with green double sparse coatings, showing great potential for low-carbon recycling applications.

Antifouling applications and fabrications of biomimetic micro-structured surfaces: A review

BACKGROUND

Since the inception of the term "Biomimetics" in 1991, the concept of utilizing natural solutions or deriving inspiration from nature to address contemporary engineering challenges has gained significant attention within the scientific community. Organisms, in order to thrive in harsh environments, have evolved a wide range of micro/nanostructured surfaces, which serve as a rich source of inspiration for the development of artificial micro/nano-structured surfaces. These natural adaptations provide valuable insights and novel pathways for fabricating such surfaces.

AIM

To conclude recent advances in micro/nano-structured surfaces from four aspects: biomimetic micro-structured surfaces of plants and animals, properties and applications of biomimetic surfaces, methods of preparations, and their limitation.

KEY SCIENTIFIC CONCEPTS

Artificial micro/nano-structured surfaces inspired by animals and plants are classified and demonstrated according to their living environment. The performances, principles and preparation techniques of natural superhydrophobic surfaces, slippery liquid-infused porous surfaces (SLIPS), anisotropic surfaces, etc. are described in detail. Moreover, the pros and cons of each preparation measures are compared and the challenges developing large-scale, cost-effective surface microstructure preparation processes are pointed out. In the end, the development trends of artificial micro/nano-structured surface are forecasted.

Engineered Sustainable Omniphobic Coatings to Control Liquid Spreading on Food-Contact Materials

The adhesion of sticky liquid foods to a contacting surface can cause many technical challenges. The food manufacturing sector is confronted with many critical issues that can be overcome with long-lasting and highly nonwettable coatings. Nanoengineered biomimetic surfaces with distinct wettability and tunable interfaces have elicited increasing interest for their potential use in addressing a broad variety of scientific and technological applications, such as antifogging, anti-icing, antifouling, antiadhesion, and anticorrosion. Although a large number of nature-inspired surfaces have emerged, food-safe nonwetted surfaces are still in their infancy, and numerous structural design aspects remain unexplored. This Review summarizes the latest scientific research regarding the key principles, fabrication methods, and applications of three important categories of nonwettable surfaces: superhydrophobic, liquid-infused slippery, and re-entrant structured surfaces. The Review is particularly focused on new insights into the antiwetting mechanisms of these nanopatterned structures and discovering efficient platform methodologies to guide their rational design when in contact with food materials. A detailed description of the current opportunities, challenges, and future scale-up possibilities of these nanoengineered surfaces in the food industry is also provided.