Surface modification of chitin nanocrystals using conducting polymer for triboelectric nanogenerator

Abstract

Single-electrode triboelectric nanogenerators (TENG) attracted much attentions due to their simplified structure, high energy conversion efficiency, flexible adaptability and wide application potential. Herein, a multifunctional, flexible and highly responsive single-electrode TENG was fabricated by grafting of conducting polypyrrole (PPy) onto the surface of chitin nanocrystals (ChNCs). ChNCs effectively improved the dispersibility of PPy in aqueous solution, thereby improving the electrochemical performance of the suspension. A single-electrode triboelectric nanogenerator (PC-TENG) was fabricated using PPy@ChNCs suspension as the electrode material and polydimethylsilane (PDMS) as the encapsulation material and friction layer. The solid-liquid double layer between the PDMS and the liquid electrode is conducive to output higher triboelectric performance. When the ratio of ChNCs to PPy was 1:2, PC-TENG has a maximum output voltage of approximately 65 V, output current of approximately 8.6 μA, and a transferred charge of about 38 nC. The power density of PC-TENG can reach 353 mW/m² with fast responsiveness and stable output performance after 1000 cycles. PC-TENG can realize human motion monitoring and tactile perception with a self-powered system. This work adopted biologically derived ChNCs to improve the dispersibility and conductivity of PPy, and the obtained PC-TENG exhibits promising application in wearable energy harvesting technology.