SnS/PEDOT:PSS composite films with enhanced surface conductivities induced by solution post-treatment and their application in flexible thermoelectric

Authors：Wu, Qinggang; Zha, Keyu; Zhang, Jiyun; Zhang, Jiaxuan; Hai, Jiefeng; Lu, Zhenhuan^*

Source：Organic Electronics: physics, materials, applications , 2023, 118: 106799.

DOI：10.1016/j.orgel.2023.106799

• Conductivity
• Flexible
• Thin-films
• Organic-inorganic composites
• Post -treatment
• Thermoelectric

Developing low-cost and high-performance thermoelectric materials is warranted. Herein, a series of flexible thermoelectric organic-inorganic composite films of tin sulfide (SnS)/poly(3, 4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) and SnS/PEDOT:PSS/multiwalled carbon nanotube (MWCNT) are prepared by drop coating. Then, a water-methanol solution is spun on the composite films to further improve the upper surface layer's conductivity. This facile water-methanol post-treatment does not affect the lower part of the film, which keeps the Seebeck coefficient of the film from being significantly reduced. As a consequence, SnS/PEDOT: PSS films show the most significant conductivity increase rate of 28.8% and the maximum power factor (PF) of 43.11 mu Wm- 1 K-2, whereas those for the SnS/PEDOT:PSS/MWCNT films are 4.5% and 44.54 mu Wm- 1 K-2, respectively. In addition, the prepared composite films show good stability in bending tests and could be applied to construct six-legged flexible thermoelectric devices to evaluate the prospects of the flexible thermoelectric application of these films. Our strategy for film design offers a new idea for thermoelectric research.

• Institution
  桂林理工大学