Sandwiched Composite Fluorocarbon Film for Flexible Electret Generator

An electret material with high charge storage ability is the key factor for fabricating high performance electret generator for wearable electronics and self-powered sensor systems. This work presents a new sandwiched composite fluorocarbon (SCF) film, which stores more residual charges compared to traditional electret materials such as dense fluorinated ethylene propylene or fibrous polytetrafluoroethylene films with the same thickness. Electret generator based on the SCF film shows a largest peak power density of ≈31.4 μW cm−2 with load resistance of 40 MΩ. Moreover, the application of the electret generator for a self-powered human breathing sensor is also demonstrated. This work offers a new strategy to enhance the output of the electret generators.