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Photothermal superhydrophobic surfaces have been demonstrated for anti-icing/deicing applications. However, preparing these materials using simple and environmentally friendly methods remains a challenge. Herein, a high-efficiency energy utilization strategy based on a photothermal-wind synergistic effect combined with superhydrophobicity has been proposed for anti-icing/deicing. Using onestep femtosecond laser direct writing technology, we modified a polyether ether ketone surface, which resulted in a superhydrophobic surface with photothermal effects. The optimized fabrication condition was laser treatment with velocity of 80 mm s−1 (LT-V80), which gave a surface possessing a high water contact angle (∼160.9°) and a low rolling angle (∼3°), and excellent self-cleaning properties were seen. Furthermore, LT-V80 showed high light absorptivity (∼94.6%), which caused the surface temperature to increase by 44.5 °C under 1.0 sun illumination. The addition of wind to the system resulted in a synergistic effect together with the photothermal and superhydrophobic properties, and caused a 87.1% reduction of the deicing time and a 220.3% increase in the icing time. This strategy also demonstrated good deicing efficiency in a cold outdoor environment. An efficient solar energy utilization strategy as demonstrated by LTV80 indicates that efficient anti-icing/deicing is possible using simple, environmentally friendly, and low cost fabrication methods. [ABSTRACT FROM AUTHOR]

Frost formation is a normal phase transition phenomenon in cold climates, while it usually brings certain troubles to human lives and production. Therefore, it is of great significance to develop frost resistant materials and key technologies. Here, a salt-philic and superhydrophobic surface is designed on a PDMS substrate by femtosecond laser direct writing technology in combination with salt–ethanol–water mixtures droplet treatment. The laser-treated PDMS embedded salt (LTP-S) surface exhibits superhydrophobicity, which alone is a property that can resist the formation of frost and enables a self-cleaning effect. Meanwhile, the salt coating further enhances the frost resistance of the surface by reducing the freezing point temperature. The LTP-S surface is revealed to perform well in frosting-defrosting cycles, washing resistance, chemical corrosion resistance, heating resistance, and long-term air exposure tests as a highly efficient and stable anti-frosting surface. This work demonstrates a facile strategy to fabricate a salt-philic and superhydrophobic surface for efficient anti-frosting. [ABSTRACT FROM AUTHOR]

Liquid droplets on superheated surfaces produce the Leidenfrost effect. This phenomenon might lead to droplet manipulation and control strategies in microfluidics and thermal management. However, Leidenfrost droplets move randomly and irregularly on superheated surfaces and the manufacturing of special surfaces to control Leidenfrost droplet movement poses great challenges. Here, we propose a simple and environment-friendly method to create heterogeneously wetting surface structures to control the spin motion of droplets on superheated brass using femtosecond laser patterning. The water contact angle of the superhydrophobic area on the surface was ∼160°, and the superhydrophilic area showed ∼7°. A z-shaped pattern was fabricated, which segmented the vapor film and influenced gas flow, and it resulted in the spinning of oval-shaped droplets analogous to a spinning egg. We used simulation to explain this phenomenon and also expanded the application of this droplet control in accelerating dissolution of solids and mechanical driving. This study provides the basis for a creative control method using the Leidenfrost droplet phenomenon, which has broad implications in steam-driven droplet motion and future fluid manipulation. [ABSTRACT FROM AUTHOR]

Crystalline and porous metal–organic frameworks (MOFs) are potential candidates for different antibacterial, photocatalytic, and adsorption applications. Moreover, multiprincipal element nanoparticles are effective against multidrug‐resistant bacteria, and combining metals with carbon nanomaterials can enhance activity. Herein, a Tri‐MOF comprised of iron, zinc, cobalt and 2‐methyl imidazole is grown together with laser‐induced graphene (LIG) powder. Electron microscopy imaging shows the successful preparation and the crystalline nature of the LIG/Tri‐MOF composite. Fourier‐transform infrared and X‐Ray photoelectron spectroscopy confirm a noncovalent mixture of LIG and Tri‐MOF. Compared with the negligible activity of LIG alone, low doses (0.91–4.54 mg mL−1) of the prepared LIG/Tri‐MOF composite show excellent antibacterial activity (≥95% bacterial removal) and a MIC of 0.6 mg mL−1 for Gram‐negative bacteria, via the gradual leaching of metal ions and organic linker from the material enhanced by bacterial aggregation near the LIG/Tri‐MOF. Compared to a mixture of separately synthesized Tri‐MOF and LIG, the LIG/Tri‐MOF composite shows improved antibacterial effects. All materials show cytotoxicity for L929 mouse cell lines, the solids showing a disrupting effect on cells grown in vitro. Performance‐enhancing combinations of various materials leading to synergistic or additive antimicrobial effects are essential strategies for minimizing the possible emergence of antibiotic‐resistant strains. [ABSTRACT FROM AUTHOR]