ULTRA-LOW WATER CONTACT ANGLE HYSTERESIS SURFACES: INTERFACIAL DESIGNS TOWARDS PRACTICAL APPLICATIONS

Abstract

Ultra-low water contact angle hysteresis (CAH<5°) is the key factor in achieving high-performance materials with various useful functions such as self-cleaning, anti-fouling, and anti-icing. However, the real implementations of such surfaces are considerably limited by the complexity in the manipulation of surface morphology/chemistry, cost-ineffectiveness, environmental friendless and lack of longevity. To this end, the main purpose of this thesis was to develop cost-effective, easy-to-process, long-lasting, fluorine-free and hysteresis-free systems, understand the fabrication principles, study the correlation between their structural and wetting properties, and explore their environmental applications. Accordingly, strategies mainly based on macromolecular self-assembly were developed to construct interfacial materials with superhydrophobic surfaces (SHS), slippery liquid-infused porous surfaces (SLIPS) or liquid-like smooth slippery surfaces (LSS). Through proper structural/molecular design, the resulting materials can support robust liquid/solid/air composite interface or highly dynamic interfaces when in contact with water, giving rise to negligible CAH and desirable longevity for practical applications. Besides, the correlation between materials properties (surface chemistry and morphology) and wetting characteristics was also investigated. On top of that, a general guideline for the design of ultra-low CAH surfaces is proposed