Human bio-electric generator: Self-powered cellulose-based wearable sensor with ultra-stretchability and low-grade...

Integrating ultra-stretchability to adapt seamlessly to human movement, while ensuring complete independence from external power sources, presents a substantial challenge for the development of advanced bioelectronic systems. This challenge becomes even more critical as the demand for wearable technologies that can both harvest energy and monitor physiological signals grows. In response to these needs, we introduce a bio-flexible thermoelectric gel composed of microcrystalline cellulose (MCC) and poly (deep eutectic solvent) (PDES), which is synthesized via a simple one-pot method for body heat harvesting in self-powered sensors. The resulting sensor demonstrates impressive performance: a Seebeck coefficient of 25.86 mV K^-1, low thermal conductivity of 0.2972 W m^-1 K^-1and a ZT value of 0.27 at room temperature. Additionally, it exhibits remarkable mechanical flexibility, with an elongation at break of 2080 %, making it highly suitable for detecting significant bodily deformations. The supramolecular hydrogen bonding network within gel ensures excellent mechanical properties and sensing sensitivity even at low temperatures (∼249.15 K). Overall, PDES-MCC_2% sensor holds great potential for smart wearable applications like generators, respiratory monitoring and motion optimization, marking a significant step toward truly autonomous, sustainable bioelectronic systems that could revolutionize daily tech interaction.