High‐Performance Thermoelectric Fibers from Metal‐Backboned Polymers for Body‐Temperature Wearable Power Devices

Metal‐backboned polymers (MBPs), with a unique backbone consisting of bonded metal atoms, are promising for optic, electric, magnetic, and thermoelectric fields. However, the application of MBP remains relatively understudied. Here, we develop a shear‐induced orientation method to construct a flexible nickel‐backboned polymer/carbon nanotube (NBP/CNT) thermoelectric composite fiber. It demonstrated a power factor of 719.48 μW ⋅m−1 K−2, which is ca. 3.5 times as high as the bare CNT fiber. Remarkably, with the regulation of carrier mobility and carrier concentration of NBP, the composite fiber further showed simultaneous increases in electrical conductivity and Seebeck coefficient in comparison to the bare CNT fiber. The NBP/CNT fiber can be integrated into fabrics to harvest thermal energy of human body to generate an output voltage of 3.09 mV at a temperature difference of 8 K. This research opens a new avenue for the development of MBPs in power supply. A novel nickel‐backboned polymer/carbon nanotube thermoelectric composite fiber is fabricated through a shear‐induced orientation method. It shows simultaneous increases in electrical conductivity and Seebeck coefficient, with a power factor of 719.48 μW m−1 K−2 as high as 3.5 times of the bare carbon nanotube fiber, opening a new avenue for the development of metal‐backboned polymers in power supply.