High-performance and high-stability bismuth selenide core thermoelectric fibers

Bismuth selenide exhibits high thermoelectric performance, which is a promising candidate for thermal-electrical energy conversion. Here, Bi2Se3 core thermoelectric fibers with K9 glass cladding were fabricated by a molten core drawing method. The 50-μm-diameter Bi2Se3 core fibers exhibit an ultrahigh Seebeck coefficient of −150.85 μV/K. In addition, it has a high dimensionless figure of merit of 0.18 (at 300 K) and a long-term stability in air. The results indicate that the drawing approach is an effective way to fabricate high-performance and high-stability thermoelectric fibers, which will have potential application in fiber-integrated thermoelectric devices.