Self-Accelerating Drops on Silicone-Based Super Liquid-Repellent Surfaces

Area of Science:

• Materials Science
• Surface Chemistry
• Tribology

Background:

• Super liquid-repellent surfaces often use unsustainable perfluoroalkylated materials.
• These materials are prone to static charge buildup, hindering performance.
• There is a need for sustainable, antistatic alternatives.

Purpose of the Study:

• To investigate drop interactions with perfluoroalkyl- and silicone-based surfaces.
• To compare the performance of sustainable low surface energy materials with antistatic properties.
• To understand the influence of surface chemistry and electrostatics on drop mobility.

Main Methods:

• Experimental analysis of drop behavior under gravity, lateral, and normal forces.
• Utilized force-and-charge instruments to measure adhesion, friction, and electrostatic effects.
• Quantum mechanical density functional theory calculations to analyze surface charge distributions.

Main Results:

• Drop mobility is dependent on surface chemistry, with sequential interactions significantly affected.
• Rolling drops are governed by adhesion and electrostatics, not friction.
• Silicone surfaces exhibit superior antistatic properties, rapidly saturating charge and enhancing drop mobility compared to perfluoroalkylated surfaces.

Conclusions:

• Surface chemistry and coupled electrostatics critically influence drop mobility.
• Silicone-based surfaces offer a promising, environmentally friendly alternative for antistatic super liquid-repellent applications.
• Understanding atomic-level charge distributions and ion lifetimes is key for designing advanced surfaces.