Surface manipulated triboelectric polymer films via direct fluorination towards high performance TENG

Triboelectric polymer with high charge density and stable output performance is the cornerstone to promote the urgent commercialization of triboelectric nanogenerators (TENGs) for various applications. In this work, the facilitated surface manipulation strategy based on direct fluorination technique is applied for triboelectric polymers to boost their performance. The Polydimethylsiloxane film as experimental samples is treated with different fluorination temperatures and times, whose characterization results demonstrated significant changes in both physical and chemical properties. The F atoms substitution in the fluorination process yields strong electron-withdrawing groups on the molecular, and a μm level fluorinated layer is formed with nanostructured surface. In the atmosphere environment, the fluorinated sample-based contact separation TENG attains a maximum charge density of about 150 μC/m2, an enhancement of 385% compared to the original sample. Meanwhile, the TENG features favorable output stability with output charge retention of about 87% in a high humidity environment and realizes sustainable operation in the long term. The enhanced charge density is attributed to the fluorinated molecular with negative electrostatic potential and lower energy level of the lowest unoccupied molecular orbital, while a rougher and denser physical structure with favorable humidity resistance allows to maintain the charge stability. Finally, the manipulation strategy for elevating the electrification performance of triboelectric polymers is summarized in terms of both elemental composition and physical structure. This work represents a feasible approach to manipulate the triboelectric polymer on surface that can be large-scale preparation and utilization, which is dedicated to guiding high performance TENGs employment towards commercialization and practical application in the near future.