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The exceptional performance of graphene has driven the advancement of its preparation techniques and applications. Laser-induced graphene (LIG), as a novel graphene preparation technique, has been applied in various fields. Graphene periodic structures created by the LIG technique exhibit superhydrophobic characteristics and can be used for deicing and anti-icing applications, which are significantly influenced by the laser parameters. The laser surface treatment process was simulated by a finite element software analysis (COMSOL Multiphysics) to optimize the scanning parameter range, and the linear array surface structure was subsequently fabricated by the LIG technique. The generation of graphene was confirmed by Raman spectroscopy and energy-dispersive X-ray spectroscopy. The periodic linear array structure was observed by scanning electron microscopy (SEM) and confocal laser imaging (CLSM). In addition, CLSM testings, contact angle measurements, and delayed icing experiments were systematically performed to investigate the effect of scanning speed on surface hydrophobicity. The results show that high-quality and uniform graphene can be achieved using the laser scanning speed of 125 mm/s. The periodic linear array structures can obviously increase the contact angle and suppress delayed icing. Furthermore, these structures have the enhanced ability of the electric heating deicing, which can reach 100 °C and 240 °C within 15 s and within 60 s under the DC voltage power supply ranging from 3 to 7 V, respectively. These results indicate that the LIG technique can be developed to provide an efficient, economical, and convenient approach for preparing graphene and that the hydrophobic surface array structure based on LIG has considerable potential for deicing and anti-icing applications. [ABSTRACT FROM AUTHOR]

The exceptional performance of graphene has driven the advancement of its preparation techniques and applications. Laser-induced graphene (LIG), as a novel graphene preparation technique, has been applied in various fields. Graphene periodic structures created by the LIG technique exhibit superhydrophobic characteristics and can be used for deicing and anti-icing applications, which are significantly influenced by the laser parameters. The laser surface treatment process was simulated by a finite element software analysis (COMSOL Multiphysics) to optimize the scanning parameter range, and the linear array surface structure was subsequently fabricated by the LIG technique. The generation of graphene was confirmed by Raman spectroscopy and energy-dispersive X-ray spectroscopy. The periodic linear array structure was observed by scanning electron microscopy (SEM) and confocal laser imaging (CLSM). In addition, CLSM testings, contact angle measurements, and delayed icing experiments were systematically performed to investigate the effect of scanning speed on surface hydrophobicity. The results show that high-quality and uniform graphene can be achieved using the laser scanning speed of 125 mm/s. The periodic linear array structures can obviously increase the contact angle and suppress delayed icing. Furthermore, these structures have the enhanced ability of the electric heating deicing, which can reach 100 °C and 240 °C within 15 s and within 60 s under the DC voltage power supply ranging from 3 to 7 V, respectively. These results indicate that the LIG technique can be developed to provide an efficient, economical, and convenient approach for preparing graphene and that the hydrophobic surface array structure based on LIG has considerable potential for deicing and anti-icing applications.

Carbon fiber reinforced plastic (CFRP) is the main material of aircraft skin. Preparing superhydrophobic anti-icing/deicing surface on the CFRP is of great importance for aircraft flight safety. In this work, a variety of multi-scale micro-nano structures were imprinted on CFRP by femtosecond laser processing, and a transition from hydrophilic to superhydrophobic CFRP was realized. After being optimized by different geometries and laser conditions, the water contact angle, which is tested at 24.3 °C and 34% humidity, increased from 88 ± 2° (pristine) to 149 ± 3° (100 μm groove) and 153 ± 3° (80 μm grid). A further anti-icing test at −10 °C (measured on the cooling platform) and 28% humidity showed that the freezing time was increased from 78 ± 10 s (pristine) to 282 ± 25 s (80 μm grid). Most importantly, the tensile tests showed that the femtosecond laser processing method did not deteriorate the mechanical properties of CFRP. This work provides great significance for aircraft passive deicing technology. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced plastic (CFRP) is the main material of aircraft skin. Preparing superhydrophobic anti-icing/deicing surface on the CFRP is of great importance for aircraft flight safety. In this work, a variety of multi-scale micro-nano structures were imprinted on CFRP by femtosecond laser processing, and a transition from hydrophilic to superhydrophobic CFRP was realized. After being optimized by different geometries and laser conditions, the water contact angle, which is tested at 24.3 °C and 34% humidity, increased from 88 ± 2° (pristine) to 149 ± 3° (100 μm groove) and 153 ± 3° (80 μm grid). A further anti-icing test at −10 °C (measured on the cooling platform) and 28% humidity showed that the freezing time was increased from 78 ± 10 s (pristine) to 282 ± 25 s (80 μm grid). Most importantly, the tensile tests showed that the femtosecond laser processing method did not deteriorate the mechanical properties of CFRP. This work provides great significance for aircraft passive deicing technology.

Superhydrophobic property is highly demanded for fiber reinforced polymer composites (FRPC) to deal with the accumulation of ice and stains. However, the traditional superhydrophobic coating prepared by nanoparticles & adhesive strategy cannot avoid the unreliable interfaces. Herein, the flexible interface-free superhydrophobic films were fabricated by infusing the paper template with PTFE and subsequent sintering treatment. The adjustable self-growing hierarchal structure could be achieved by crystallization of PTFE tuned by cooling rate. By pressure-assisted integrated molding, the optimized textured film obtained at a cooling rate of 2 °C/min was employed to FRPC with reliable interfacial bonding. The prepared superhydrophobic FRPC (SH-FRPC) could withstand at least 800 cycles' tape peeling, 200 cycles' sandpaper friction and 24.8 m/s water impact (We = 16908) with unchanged superhydrophobicity. Besides, the worn surface by extreme effect recovered its superhydrophobicity by specific sandpaper friction in <10 s or reheat treatment at 380 °C. What's more, the prepared SH-FRPC shown excellent self-cleaning and anti-icing capacities compared with the original FRPC. With outstanding operational feasibility and retention of mechanical properties, the multi-functional FRPC is attractive for applications in rainy or dusty environments. [Display omitted] • An interface-free superhydrophobic film with self-growing hierarchal structure tuned by cooling rate is prepared. • The superhydrophobic fiber reinforced polymer composite (FRPC) is prepared by pressure-assisted integrated molding. • The superhydrophobic FRPC surface has high tape-peel/abrasion/water-impact resistance and strong interfacial bonding. • The superhydrophobicity could be recovered by sandpaper friction or heating treatment expediently. [ABSTRACT FROM AUTHOR]

THE SUBJECT OF THE PRESENT PAPER is the applicability of hydrophobic surfaces for passive anti-icing protection. The experiments were focused on freezing droplets and on various droplet impingement and deformation scenarios. Droplet impact was investigated using high-speed camera for surfaces with different physico-chemical properties. To investigate the difference in droplet behavior on the surfaces with different wettability the steel and the aluminum plates were used and compared with specially designed surfaces characterized by a low surface energy. The influence of air humidity on droplet freezing was confirmed. The effective prevention of icing was observed only if humidity was removed from the system during the experiment. [ABSTRACT FROM AUTHOR]

Superhydrophobic coating acting as ice prevention is of great interests for academic researches and real-world applications, but whose application is challenging to obtain satisfactory anti-icing performance, remain long-term water repellency and strong mechanical stability, as well as adopt environmental-friendly and commercializable methods. Herein, we report a fluorine-free and low-cost approach introduced by self-assembly deposition of nanoparticles for the fabrication of superhydrophobic anti-icing coating applied onto aeronautical composite. Regarding to the as-prepared coating, multi-scale hierarchical structure with low intrinsic surface energy was demonstrated by morphological and compositional characterizations. Such coating displayed reasonably good repellency against water and acid/alkaline droplets, long-time durability, and superior mechanical stability with compared to recent reports. Besides, the mechanism of anti-icing performance by superhydrophobicity was explained. The resultant coating could delay ice accretion by 120 min and exhibit low ice adhesion strength at 53.6 kPa, thus promising to achieve anti-icing applications for aerofoils, wind turbine blades, etc. Image 1 • Multi-scale hierarchical structure is formed within the superhydrophobic coating. • Such coating exhibits excellent chemical durability and strong mechanical stability. • The mechanism of anti-icing performance by superhydrophobicity is explained. • As-prepared coating can delay ice accretion and reduce ice adhesion. [ABSTRACT FROM AUTHOR]