Ultra-Durable and Transparent Self-Cleaning Surfaces by Large-Scale Self-Assembly of Hierarchical Interpenetrated Polymer Networks

Abstract

In nature, durable self-cleaning surfaces such as the Lotus leaf rely on the multiscale architecture and cohesive regenerative properties of organic tissue. Real-world impact of synthetic replicas has been limited by the poor mechanical and chemical stability of the ultrafine hierarchical textures required for attaining a highly dewetting superhydrophobic state. Here, we present the low-cost synthesis of large-scale ultradurable superhydrophobic coatings by rapid template-free micronano texturing of interpenetrated polymer networks (IPNs). A highly transparent texture of soft yielding marshmallow-like pillars with an ultralow surface energy is obtained by sequential spraying of a novel polyurethane-acrylic colloidal suspension and a superhydrophobic nanoparticle solution. The resulting coatings demonstrate outstanding antiabrasion resistance, maintaining superhydrophobic water contact angles and a pristine lotus effect with sliding angles of below 10° for up to 120 continuous abrasion cycles. Furthermore, they also have excellent chemical- and photostability, preserving the initial performance upon more than 50 h exposure to intense UVC light (254 nm, 3.3 mW cm(-2)), 24 h of oil contamination, and highly acidic conditions (1 M HCl). This sprayable polyurethane-acrylic colloidal suspension and surface texture provide a rapid and low-cost approach for the substrate-independent fabrication of ultradurable transparent self-cleaning surfaces with superior abrasion, chemical, and UV-resistance.

Design Rules for Laser‐Treated Icephobic Metallic Surfaces for Aeronautic Applications

“…Among the several approaches that can be used to generate lotus leaf‐like structures on surfaces, [ 24–26 ] short/ultrashort (S/US) laser pulses present several advantages. The material removal takes place locally at the zone where the laser beam is interacting with the substrate and also causes a limited chemical surface modification.…”

Bio‐Derived Co2P Nanoparticles Supported on Nitrogen‐Doped Carbon as Promising Oxygen Reduction Reaction Electrocatalyst for Anion Exchange Membrane Fuel Cells

“…The peaks of the P 2p spectra located at 130.3 and 132.6 eV were ascribed to PO and phosphide (CoP), respectively. For the Co 2p spectra, the peaks located at 778.8 and 793.7 eV were assigned to CoP . CoO and CoN x species were confirmed by the peaks centered at 780.1 and 795.1 eV, and 782.9 and 797.9 eV, respectively.…”

“…For the Co 2p spectra, the peaks located at 778.8 and 793.7 eV were assigned to CoP. [28,29] CoO and CoN x [30] species were confirmed by the peaks centered at 780.1 and 795.1 eV, and 782.9 and 797.9 eV, respectively. Shake-up satellite peaks could also be seen at 786.6 and 803.4 eV.…”

Self‐Healing Functional Surfaces

“…Different roughness‐directing elements have been used, such as single particles or aggregates embedded in a polymer film, particles (or aggregates) covered or functionalized with a thin layer of low surface energy molecules and deposited on a surface, porous materials, highly heterogeneous interpenetrated networks, and responsive polymers that change their state of agglomeration upon application of external stimuli. It should be highlighted that, regardless of the strategy or roughness‐shaping elements chosen a sufficient reservoir of the both, the low surface energy and the roughness‐shaping components need to be provided, namely, for multiple healing events.…”