Simple, low-cost, water-processable n -type thermoelectric composite films from multiwall carbon nanotubes in polyvinylpyrrolidone

• DOI: 10.1016/j.synthmet.2016.11.014
• Publication Date: 2016-11-18T17:31:48Z
• Authors: Ruben Sarabia-Riq...; John Craddock; E. Ashley Morris; David Eaton; Rodney Andrews; John Anthony; Matthew C. Weisen...
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract A significant challenge facing the advancement of organic thermoelectric devices is developing low-cost, solution-processable, air-stable, high performance n -type materials. In this work, we fabricate multiwall carbon nanotube (MWCNT)/polyvinylpyrrolidone (PVP) composite films by simply dispersing MWCNTs and PVP in water and spraying the resulting ink onto a substrate. We report a switch in the Seebeck coefficient of the MWCNTs from p -type to n -type behavior, even when the concentration of MWCNTs is as high as 90 wt.% in PVP. Additionally, we observe a great enhancement of the thermoelectric properties of the material when low quantities of polyethyleneimine (PEI) are added, reaching an n -type power factor of 1.98 μW m −1 K −2 for a composite film containing 30 wt.% MWCNTs in PVP and 0.05 PEI/MWCNT wt. ratio. Furthermore, the material shows good air and thermal stability. We believe that the low-cost of the components, the air-stability and the simplicity of the water-processable system make PVP/MWCNTs a potential n -type organic material for future thermoelectric applications.