Quantifying Dielectric Material Charge Trapping and De-Trapping Ability Via Ultra-Fast Charge Self-Injection...

Area of Science:

• Materials Science
• Nanotechnology
• Energy Harvesting

Background:

• Triboelectric nanogenerators (TENGs) utilize the triboelectric effect for energy harvesting.
• Air breakdown effect enhances charge injection in dielectric polymers for TENGs.
• Characterizing charge trapping and its impact on TENG startup is crucial for applications.

Purpose of the Study:

• To develop an ultra-fast charge self-injection technique for TENGs.
• To introduce a standard method for quantifying charge trapping and de-trapping in triboelectric materials.
• To analyze the relationship between dielectric trap states and charge transport.

Main Methods:

• Proposed an ultra-fast charge self-injection technique based on self-charge excitation.
• Developed a standard method to quantify charge trapping/de-trapping abilities of 23 tribo-materials.
• Systematically analyzed the distribution of dielectric trap states and charge transport.

Main Results:

• Quantified charge trapping and de-trapping abilities of 23 traditional tribo-materials.
• Established that the charge de-trapping rate dictates the reactivation and failure of secondary self-charge excitation (SSCE).
• Achieved ultra-high charge density (2.67 mC m^-2) and ultra-fast SSCE startup time using a 15 µm poly(vinylidene fluoride-trifluoroethylene) film.

Conclusions:

• The de-trapping rate of charges is critical for SSCE reactivation and failure.
• The developed method provides a standard for material selection in TENGs.
• This research offers insights into charge transport in dielectrics and breaks records in material modification for TENGs.