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Superhydrophobic coating is widely used due to its waterproof and self-cleaning properties. Carbon soot (CS) nanoparticles are naturally superhydrophobic and non-toxic which are superior to other superhydrophobic coating. However, the weak binding force of the CS nanoparticle layers hinders their practical application. In this study, micro-nanostructured PET-CS superhydrophobic coatings were prepared by a simple method. The obtained coatings presented durable superhydrophobicity and underwater stability, which are superior to PDMS-CS coatings and CS layers. The coating surfaces demonstrated superhydrophobicity under a water pressure of 13.72 kPa for up to 16 days. The surface could withstand water flush for more than 15 min. The coatings also demonstrated good mechanical stability and maintained superhydrophobicity after an abrasion length of 8 m. The stable long-lasting underwater superhydrophobic surface is of great importance for marine applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The relationship between anti-icing and anti-condensation properties was studied. • The coating surfaces with cavities-pore combined structures were prepared. • Surfaces with cavity-pore combined structures displayed good anti-icing properties. • Surfaces with uniform porosity presented notable anti-condensation performance. To address the issues caused by ice accretion, researchers have made various attempts to obtain anti-icing surfaces, among which superhydrophobic surfaces have been approved to be an ideal candidate for anti-icing applications. Although extensive research has been conducted to date, the relationship between the anti-icing performance and the anti-condensation performance of superhydrophobic surfaces has yet to be investigated. In this study, superhydrophobic coatings with different surface microstructures were prepared. Tuning of surface morphology was conducted by controlling molar ratio of SiO 2 nanoparticles and polyester powders. The superhydrophobic coatings with uniform surface microstructures exhibit anti-condensation performance. Superhydrophobic coatings with cavities-pore combined surface structures demonstrated superior anti-icing performance to other coatings. The relationship between the anti-icing and anti-condensation performance was investigated. It is verified that the anti-condensation performance of the superhydrophobic surface do not have a simple correlation with the anti-icing performance. Furthermore, the coatings present oil repellency, durable superhydrophobicity and anti-fouling properties. [ABSTRACT FROM AUTHOR]

Abstract Among different types of anti-icing coatings, superhydrophobic coatings have attracted considerable attention due to their water repellency and low heat-transfer rate. However, condensation on superhydrophobic surfaces at low temperatures usually causes an increase in ice adhesion because of the induced wetting of micro- and nanostructures. By tuning the weight ratio of surface-modified nanoparticles to unmodified ones, five superhydrophobic coatings with different structural features at the microscale were developed. Ice-adhesion strength and ice-nucleation temperature were studied, together with the effect of moisture condensation on ice adhesion. It was found that the ice-adhesion strength and icing temperature of these coatings do not necessarily follow the same order among these surfaces because of different mechanisms involved. Surface roughness is inadequate to describe the necessary surface features that critically affect the anti-icing behavior of the coatings. Detailed topology/geometry has to be considered when designing icephobic coatings. Superhydrophobic coatings can be adopted for icephobic applications once the surface topology is carefully designed. Graphical abstract Unlabelled Image Highlights • Superhydrophobic coatings with distinct surface topology are fabricated. • Icing temperature and probability of the coatings were statistically analyzed. • Not all superhydrophobic coatings present the same desirable icephobicity. • Surface geometry and surface energy play important roles in the ice adhesion. • Superhydrophobic coating can be icephobic with careful design of surface topology. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fluorine-free icephobic coating has been developed based on silicone-epoxy hybrid resin. • The icephobic coating can be prepared by spraying coating and cured at room temperature. • The design of dual-sized nanoparticles leads to better icephobicity and mechanical properties. • The coating keeps an ice-adhesion strength below 100 kPa after UV irradiation and sand erosion. • Mechanical properties and durability are compared with literature reported coatings. Abstract Ice accumulation leads to improper functioning or even damages to ships, offshore platforms, sports facilities and land buildings in cold climate regions. Although fluorochemicals have demonstrated attractive performance for icephobic applications, their use has been restricted due to health and environmental concerns. Here, we present a facile method to fabricate fluorine-free icephobic coatings with potential applications for outdoor facilities and structures. The coating consists of a silicone-epoxy hybrid resin, polydimethylsiloxane (PDMS) and SiO 2 nanoparticles with different sizes. Particularly, the use of different sized (10–20 nm and 200 nm) SiO 2 nanoparticles results in excellent icephobicity and mechanical properties. The mechanical properties and durability of the coating were analysed according to respective test standards and compared with other reported icephobic coatings. The durable icephobic potency of the coatings is very promising as a sustainable green solution for various practical anti-icing applications. [ABSTRACT FROM AUTHOR]

Ice accretion and accumulation pose serious challenges for maintaining the operation and performance of outdoor facilities in cold climate. Epoxy resin, with a wide range of formulation possibilities, is widely used as protective coatings for outdoor facilities. However, bisphenol A (BPA), a key ingredient of conventional epoxy, is known to interfere with human's natural hormones and cause various disorders in the body system. Reduction or complete elimination of the usage of BPA is therefore high in the agenda of the coatings industries. In this study, a transparent, anti-icing, bio-based epoxy coating was developed for room-temperature processing. As a result of hydrophobic treatment with addition of silanes, the glass-transition temperature and anti-icing performance of bio-based epoxy resin increased significantly. The optimum coating exhibited good water repellency and ice-adhesion strength as low as 50 kPa at − 20°, which was half of the widely accepted threshold value of 100 kPa for icephobic coatings. The icing delay time was much delayed compared with that of an uncoated glass substrate. To further demonstrate the anti-icing performance of the optimized coating, supercooled-water dripping on coated wooden outdoor floors and wooded boards was conducted at − 15 °C, superior anti-icing performance was observed on the coated substrates. [ABSTRACT FROM AUTHOR]

Self-cleaning coatings with excellent water-repellence and good mechanical properties are in high demand. However, producing such coatings with resistance to mechanical abrasion and environmental weathering remains a key challenge. Mechanically robust coatings based on tetraethylorthosilicate (TEOS) and glycidoxypropyltriethoxysilane (Glymo) have been prepared using a sol–gel method. Emphasis is given to the addition of Glymo, an epoxy silane which creates an organic matrix that blends with the inorganic Si O Si matrix formed from the TEOS. The combination of the blended matrix produced coatings with good adhesion to substrates and improved mechanical properties. Fluoroalkylsilane (FAS) and silica fillers were introduced to increase the hydrophobicity of the coating. It was found that the water contact angle (CA) of these coatings increases from 115° to 164° upon decreasing filler size from 1–5 μm to 10–20 nm. The sliding angle (SA) for coatings with 15 wt.% loading of 10–20 nm silica is around 2°. UV weathering does not show significant effect on the properties of the coatings. Mechanical properties and performances including hardness, Young's modulus, coating adhesion and abrasion resistance were systematically analyzed. In the current work, a simple self-cleaning test, which measures the extent of dirt accumulation and subsequent removal by water spray, was performed. The coatings with 15 wt.% loading of 10–20 nm silica particles show the best self-cleaning performance both before and after mechanical abrasion. The developed coating process is simple and can be easily scaled-up for large surfaces that require self-cleaning function. [ABSTRACT FROM AUTHOR]

A breathable anti-condensation coating with robust superhydrophobicity has been developed by a simple, low cost and scalable method. The coating displays durable performance in continuous condensation test. In addition, the coated area maintains superhydrophobicity after removal of the coated surface. [Display omitted] • A breathable environmental friendly anti-condensation surface has been developed. • The coated cementitious substrates present a condensation delay time of 50 min. • The tolerance against condensation was verified according to ISO 6270 standard. • Mechanical tests show good adhesion between the coating and the substrate. • A comparison with other reported anti-condensation coatings has been done. Condensation poses a serious challenge to the mechanical durability and sustainable development of modern buildings in tropical environment. Moisture condensation and absorption in architecture causes inconvenience and requires extra maintenance measures. A mechanically durable anti-condensation coating that displays very low affinity with moisture is promising for applications on wall and ceiling of buildings. A main challenge in the fabrication of anti-condensation surface lies with the requirements of preventing water accumulation on the surface while maintaining the breathability of substrate. In this study, a breathable anti-condensation coating has been developed on cementitious substrates based on bio-based epoxy resins. The coating presented water repellency and a condensation delay time of 50 min when compared to the uncoated counterpart at a sub-cooled temperature of 8 °C. The excellent tolerance against condensation was verified after 200 h continuous condensation test according to ISO 6270 standard. The coating also displayed good breathability and moisture resistance, which are key to the inhibition of bacteria growth and structural deterioration in architecture. Moreover, the superhydrophobic sample demonstrated a 9.7% increase in thermal conductivity over the uncoated substrate. Mechanical tests showed good adhesion between the coating and the substrate. The coated area of cementitious substrate maintained its superhydrophobicity even after the bulk coating was removed. The coating also displayed superior mechanical durability over the state-of-the-art anti-condensation coatings. The reported method provides a practically useful and environmentally friendly solution to mitigate water absorption problem of concrete based architectures. [ABSTRACT FROM AUTHOR]

Ice accretion on automobiles, aerospace components, precision instruments, and photovoltaic devices detrimentally affect their performance and increase the maintenance cost. Despite significant efforts devoted to the investigation of anti‐icing coatings in the past decades, mechanically robust and transparent anti‐icing coatings are rarely reported. In this study, titanate nanotubes are used as filler to prepare mechanically robust anti‐icing coatings with a sol‐gel method. Specially, the effect of dispersion status of nanotubes on the transmittance, surface roughness, and water repellency is investigated. The optimized smooth, transparent coating exhibits higher water repellency and better anti‐icing performance in terms of ice‐adhesion strength, icing delay time, and ice‐nucleation temperature than the rough one. Much higher hardness and scratch resistance than that of commercially available icephobic or anti‐icing coatings is obtained on the smooth, transparent sample; the coating also presents good adhesion to the substrate. Dispersion status of elongated titanate nanotubes in sols is investigated. By applying mechanical force for different duration, coatings with different transmittance and water repellency are obtained. Comparison of coatings with distinct dispersion status of nanotubes verifies that coatings with uniform dispersion of nanotubes exhibit better anti‐icing performance than those with aggregated ones. [ABSTRACT FROM AUTHOR]