Recycling waste rubber bands and human hair into complementary surface structure-based tribo-layers for ultrahigh power generation and self-powered health monitoring

Abstract

Here, we mitigate hazardous waste materials such as rubber band and human hair waste by reusing the waste in triboelectric energy harvesters, thereby boosting resource recycling and realizing renewable energy sources, dramatically reducing the threats that the waste sources pose to the environment, humanity, and wildlife. We have successfully initiated the utilization of waste rubber bands into triboelectric nanogenerator (TENG) technology by an economic, simple, and eco-friendly chemical processing of waste rubber bands to fabricate a high-performance negative tribo-layer. Due to the strong triboelectrification between the waste human hair film and the waste rubber band film of complementary surface structures, a powerful electrical output of 7.24 KV and 196.44 μA, along with a high output power density of 28,459.43 μWcm⁻², was generated from a fabricated bio-TENG with dimensions of 5 × 10 cm², which represents a significant improvement over the recent advances in waste material-based TENGs. The lightweight and flexible rubber band-based negative side of the TENG device is capable of efficiently harvesting friction with natural hair and human finger tapping with significant selectivity, thereby exhibiting excellent prospects in self-powered smart human health monitoring. By realizing the systematic utilization of slowly degradable waste materials in TENG devices, we not only solve a problem in waste management systems and mitigate serious environmental issues but also pave the way for developing large-scale, cost-efficient, green self-charging power cells and self-powered modern health care applications. Therefore, we propose that this work can represent a great approach toward a circular bioeconomy.