Green Energy from Edible Materials: Triboelectrification-Enabled Sustainable Self-Powered Human Joint Movement Monitoring

Green energy from the ambient environment is crucial for reducing global pollution and moving toward sustainable development goals for the future. Triboelectric nanogenerators (TENGs) are emerging as green energy sources, from which the energy can be generated from the ambient environment in the form of mechanical motions. Incorporating novel edible materials to fabricate triboelectric layers and devices is one of the ways to reduce global pollution, which can also reduce electronic and plastic wastes. Herein, polysaccharides like starch- and cellulose-enriched edible food ingredients such as rice flour, wheat flour, gram flour, and semolina are used to make the active layers of the TENG device, which is named EM-TENG. The edible materials are incorporated into a biocompatible polymer, polyvinyl alcohol (PVA), to make a flexible film, and fluoroethyl polymer is used as the opposite layer for the complete fabrication of the device. The edible material-incorporated PVA film is tested for biodegradability, and the electrical response of the EM-TENG device was studied. The rice flour-based device generates a maximum electrical response of 96 V and 0.6 μA with a load resistance of 70 MΩ giving a power density of 300 μW/cm2. The device is further tested for its real-time application in joint motion monitoring by scaling up and attaching it to various human body parts such as fingers and joints. The EM-TENG device proves from the tests and analysis that a promising device candidate for powering up electronic components has a huge potential for use in health care and rehabilitation in the near future.