Achieving High Thermoelectric, Stretchable, and Self-Healing Capabilities in Self-Supported PEDOT:PSS/Nafion/Poly(vinyl Alcohol) Composites for Wearable Thermoelectric Power Generators and Sensors
Lijun Lu, Zhixiong Liao, Dongxia Xian, Boyu Zhao, Chunmei Gao, Lei Wang
Abstract
In wearable devices, the escalating demand for self-powered and low-maintenance cost energy has emphatically underscored the significance of organic thermoelectric materials (OTMs). Nevertheless, a widespread challenge is that most high-performance OTMs are prone to damage, which significantly hampers their reliability and longevity. This study presents a flexible and self-healing thermoelectric composite comprising poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/Nafion/poly(vinyl alcohol) (PVA) and explores its application in self-powered strain and sensors. The results reveal that the self-healing thermoelectric material showcases impressive flexibility, with a tensile strain capacity of 141% and a peak tensile strength of 26 MPa. Notably, it demonstrates superior thermoelectric performance, featuring a remarkable conductivity of 424.14 ± 34.28 S·cm –1, the peak value reported thus far for self-healing and stretchable all-organic thermoelectric materials, along with a notable power factor of 8.70 ± 0.81 μW·m –1 ·K –2 . The dynamic interplay of hydrogen bonding among PEDOT:PSS, Nafion, and PVA facilitates swift and effective repair of scratches and cuts, sustaining 76.1% of the initial thermoelectric performance. Furthermore, utilizing the composite, a thermoelectric generator was assembled with a power output of 120.64 nW at a temperature difference of 36 K. In addition, sensitive self-powered strain and temperature sensors were successfully developed. This work introduces an effective method for achieving intrinsic self-healing in OTMs, resulting in enhanced electrical conductivity and power generation capabilities.