Electrostatic charging of fluoropolymer and its application for triboelectric energy harvesting

Abstract

More than 80 % of global energy consumption depends on fossil fuels, and this trend will not change for decades. Energy consumption is also increasing due to the rapid advances in portable electronic devices and wireless sensors. Therefore, environmentally friendly energy harvesting technology that converts various energy sources such as solar energy, wind power, ocean waves, and ambient mechanical vibrations into electric energy have actively studied. Among them, triboelectric nanogenerator regard as one of the most promising technique for self-powering of small electronics. In this paper, the study of electrostatic charge and its application of fluorinated polymers, which have the greatest influence on the performance of triboelectric nanogenerators, have been studied. In the first part, energy generator inspired by lotus-leaf is introduced. Electrical energy is generated due to the formed electric double layer (EDL) at the interface between fluoropolymer and water drop. In addition, the theoretically efficient superhydrophobic structure was calculated and observed through electrical generation. In the second part, the novel fluoropolymer is introduced as a candidate for the triboelectric series. The new PFDMA shows strategy of fabricating roughened surface under mild condition and first analysis on effective work function and electrical output of PFDMA. Also, superhydrophobic surface of PFDMA shows energy harvesting from water drops. In the third part, the intrinsic characteristic of PFDMA with improved performance by annealing effect is focused. The improvement of electrical characteristics was observed due to the increased crystallinity and the better orientation of the fluoroalkyl group depending on the annealing temperature. Based on the analysis, experimental guideline of novel tribo materials of TENG is suggested.