Greatly Enhanced Thermoelectric Performance of Flexible Cu<sub>2−x</sub>S Composite Film on Nylon by Se Doping
Xinru Zuo,
Xiaowen Han,
Zixing Wang,
Ying Liu,
Jiajia Li,
Mingcheng Zhang,
Changjun Huang,
Kefeng Cai
Affiliations
Xinru Zuo
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Xiaowen Han
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Zixing Wang
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Ying Liu
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Jiajia Li
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Mingcheng Zhang
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Changjun Huang
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
Kefeng Cai
Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, School of Materials Science & Engineering, Tongji University, Shanghai 201804, China
In this work, flexible Cu2−xS films on nylon membranes are prepared by combining a simple hydrothermal synthesis and vacuum filtration followed by hot pressing. The films consist of Cu2S and Cu1.96S two phases with grain sizes from nano to submicron. Doping Se on the S site not only increases the Cu1.96S content in the Cu2−xS to increase carrier concentration but also modifies electronic structure, thereby greatly improves the electrical properties of the Cu2−xS. Specifically, an optimal composite film with a nominal composition of Cu2−xS0.98Se0.02 exhibits a high power factor of ~150.1 μW m−1 K−2 at 300 K, which increases by ~138% compared to that of the pristine Cu2−xS film. Meanwhile, the composite film shows outstanding flexibility (~97.2% of the original electrical conductivity is maintained after 1500 bending cycles with a bending radius of 4 mm). A four-leg flexible thermoelectric (TE) generator assembled with the optimal film generates a maximum power of 329.6 nW (corresponding power density of 1.70 W m−2) at a temperature difference of 31.1 K. This work provides a simple route to the preparation of high TE performance Cu2−xS-based films.
