High-Performance Flexible Triboelectric Nanogenerator Based on Environmentally Friendly, Low-Cost Sodium Carboxymethylcellulose for Energy Harvesting and Self-Powered Sensing

The urgent need to address energy consumption and environmental issues has triggered a strong interest in triboelectric nanogenerators (TENGs), and thus, the exploration of novel materials with environmentally friendly characteristics and low cost for the preparation of high-output TENGs has shown great attraction. Herein, we proposed a method to increase the electron-donating ability of sodium carboxymethylcellulose (CMC) by adding polyethyleneimine (PEI) to CMC through simple physical mixing. By systematically adjusting and optimizing the CMC concentration and its content with PEI, it not only greatly improves the tribopositive performance of CMC but also makes the prepared film have excellent flexibility. The obtained CMC/PEI-TENG open-circuit voltage and short-circuit current can reach 385 V and 51 μA, respectively, with a maximum output power density of 1.056 mW/cm2, which can easily power 320 commercial LEDs. Moreover, the triboelectric output is improved by approximately 1.7 times compared to that of pure phase CMC film-based TENG. In addition, the new TENG shows great potential as a self-powered power source and sensor. The novel CMC-based composite film TENG proposed in this study provides a new idea for the development of environmentally friendly TENGs.