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

Abstract

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/cm 2 . 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.

Environmentally friendly natural materials for triboelectric nanogenerators: a review

“…The SL-TENG was used to successfully power a stopwatch and thermometer. A study by Prasanna et al 144 compared the properties of TENGs (EM-TENG) based on four different types of starch (Fig. 10a and b), rice flour (RF), wheat flour (WF), gram flour (GF), and coarse flour (SM), where 5 wt% RF, WF, GF, and SM were added to PVA as different tribopositive layers and FEP was used as the tribonegative layer.…”

“…Natural materials-based devices can be used to harvest wind and mechanical energy. 75,112,135 In addition, they can also be used as monitors of the environment, 109 human motion, 144,145 and sweat, 150 as well as for powering small devices such as calculators and watches. 95,164 Moreover, progress has been made in developing natural-materials-based TENGs for use in wearable and implantable biomedical devices.…”

“…144 (b) Photographs of four starchy foods and a comparison of their output voltage and current.144(c) Charge transport pathways of the pure PVA and RF-incorporated PVA. 144 (d) Photograph of RF-PVA film degradation over 16 days 144. (e) Use of the EM-TENG to monitor human joint motion in real time 144.…”

Sustainable Triboelectric Materials for Smart Active Sensing Systems

“…A large amount of cellulose is also contained in commonly used edible materials such as buckwheat, [45] white potatoes, [46] and peppers, [47] which are major components of daily food products and are one of the main sources of cellulose extraction. [48] Additionally, bacterial cellulose (BC) fabricated by biotechnological assembly methods is made of fiber bundles with a network structure, [49] which is mainly derived from bacteria on decaying fruits and vegetables. The unique origin of BC extends the application of cellulose materials in new properties and functions.…”

Induced Piezoelectricity in Cotton-Based Composites for Energy-Harvesting Applications

“…The use of green materials which are biocompatible and easily degradable in the field of electronics is of high importance. Harnessing green energy from natural surroundings using green and sustainable materials can be a big step in sustainable and alternative energies. , Cellulose is one of the most abundant natural polymers with better piezoelectric properties, due to the presence of the non-centrosymmetric arrangement of the hydroxyl groups . Ram et al prepared nylon 11 and biomass-derived cellulose nanocrystal (CNC) composites using the solution casting route, which generated a maximum output voltage of 6.95 V at ∼23 N forces.…”