Ti-doping inducing high-performance flexible p-type Bi0.5Sb1.5Te3-based thin film

Bi2Te3-based flexible thermoelectric power generator is a competitive candidate for wearable electronics. However, the strongly coupled Seebeck coefficient and electrical conductivity limits thermoelectric performance of p-type Bi0.5Sb1.5Te3-based flexible thin films (f-TFs). In this work, we report Ti-doping by a magnetron co -sputtering method can strengthen the texture orientation of as-prepared Bi0.5Sb1.5Te3-based f-TFs and corre-spondingly contribute to a high electrical conductivity of 532.69 S cm-1 at room temperature. Under simulta-neously optimized carrier concentration (nh), a high Seebeck coefficient of-196.15 mu V K-1 and an high room -temperature power factor of-19.67 mu W cm-1 K-2 have been achieved. A 3 single-leg flexible thermoelectric device demonstrates high applicability. Simultaneously, the as-prepared Ti-doped Bi0.5Sb1.5Te3 f-TFs and device demonstrate high bending resistance as evidenced by the <10% change of thermoelectric performance before and after bending. Our study indicates that Ti-doping can simultaneously tune the texture orientation and nh of Bi0.5Sb1.5Te3-based f-TFs and achieve high thermoelectric performance.