Control of Triboelectrification by Engineering Surface Dipole and Surface Electronic State

Area of Science:

• Surface Science
• Materials Science
• Tribology
• Physical Chemistry

Background:

• Triboelectrification, the charge transfer between materials upon contact, is a widely observed phenomenon.
• A systematic, fundamental understanding of the surface-level mechanisms governing triboelectrification remains incomplete.
• Existing models often lack detailed insights into how surface properties dictate charge generation and polarity.

Purpose of the Study:

• To systematically investigate the role of surface potential, specifically surface dipoles and electronic states, in controlling triboelectrification.
• To elucidate how surface functionalization influences the magnitude and polarity of triboelectric charges.
• To provide a deeper, atomistic understanding of the triboelectrification mechanism and charge retention.

Main Methods:

• Controlled modification of material surfaces using various electron-donating and -withdrawing functional groups.
• Characterization of surface potential, including surface dipoles and electronic states.
• Experimental measurement of triboelectric charge generation and polarity.
• First-principles simulations to confirm atomistic origins and charge retention sites.

Main Results:

• Demonstrated that surface dipoles and electronic states, modulated by functional groups, are key determinants of triboelectrification.
• Showed that even a monolayer modification (<1 nm) can significantly alter the conventional triboelectric series.
• First-principles simulations confirmed the atomistic basis of charge transfer and identified locations of charge retention post-contact.

Conclusions:

• Surface potential, particularly surface dipoles and electronic states, fundamentally governs triboelectrification.
• Tailoring surface functional groups offers a powerful method to control triboelectric charging behavior.
• This research provides novel insights into the fundamental mechanisms of triboelectrification and charge localization.