Nanoarchitectonics of High-Performance and Flexible n-Type Organic–Inorganic Composite Thermoelectric Fibers for Wearable Electronics
Jiajia Li, Xinyang He, Junhui Wang, Suiyuan Zhu, Mingcheng Zhang, Changxuan Wu, Guoying Dong, Ruiheng Liu, Liming Wang, Lidong Chen, Kefeng Cai
Abstract
Since most conductive polymers are p -type, developing high-performance n -type organic–inorganic composite thermoelectric (TE) fibers is a great challenge. Herein, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-coated Ag 2 Te nanowires (PC-Ag 2 Te NWs) were prepared by a liquid-phase reaction using PEDOT:PSS-coated Te nanowires (PC-Te NWs) as templates, and the PEDOT:PSS/PC-Ag 2 Te NWs composite fibers were then prepared by wet spinning. As the content of PC-Ag 2 Te NWs increases, the composite fiber changes from p -type to n -type. The PEDOT: PSS coating greatly improves the dispersibility of Ag 2 Te NWs in the PEDOT: PSS matrix, resulting in an ultrahigh content of 87.5 wt % of PC-Ag 2 Te NWs in the composite fibers, which exhibited a Seebeck coefficient of −61.3 μV K –1 and a power factor of 65.3 μW m –1 K –2 . The power factor value is higher than those of previously reported n -type composite TE fibers. Contrary to the estimated thermal conductivity in other reports, in this work, the thermal conductivity of the composite fibers was measured via a transient photoelectrothermal (TPET) technique. In addition, the composite fiber has good tensile properties and mechanical strength, elongating at a break of 47.37% and a tensile stress of 6.59 MPa. For an application demonstration, a self-powered temperature sensor was assembled, which can utilize the vertical temperature difference between the human body and the environment and respond quickly to a small temperature difference.