Ethylcellulose and bismuth sodium titanate-barium zirconate titanate (BNT-BZT) composite fibers for triboelectric energy harvesting

Green cellulose and toxic-free/rare earth-free nanomaterials are promising towards the development of triboelectric nanogenerators (TENGs) as energy harvesters for sustainable electronics. In this study, ethylcellulose (EC) and bismuth sodium titanate-barium zirconate titanate (BNT-BZT) are used as raw materials. An EC and BNT-BZT composite fiber mat was prepared by electrospinning and used as a positive triboelectric layer in a friction nanogenerator, while fluorinated ethylene propylene (FEP) was used as a negative triboelectric layer. After optimizing the electrospinning parameters and characterizing the materials, the developed TENG output power was studied as a function of the BNT-BZT doping concentration in the EC. At 2 wt% of doping, the output voltage of the TENG has a 3-fold increase compared with that obtained with a pure EC mat as the positive triboelectric layer. In addition, the TENG showed good output performance and operating stability after exposure to high temperature (70 ºC) and relative humidity (90 %). The maximum output power density of 134 μW/cm² was obtained at a load resistance of 210 MΩ, showing good prospects in powering Internet of Things (IoT) sensor nodes.