TY - JOUR
T1 - Enhanced thermoelectric performance of PEDOT:PSS flexible bulky papers by treatment with secondary dopants
AU - Mengistie, Desalegn A.
AU - Chen, Chang Hsiao
AU - Boopathi, Karunakara M.
AU - Pranoto, Ferry W.
AU - Li, Lain-Jong
AU - Chu, Chih Wei
PY - 2015/1/14
Y1 - 2015/1/14
N2 - For inorganic thermoelectric materials, Seebeck coefficient and electrical conductivity are interdependent, and hence optimization of thermoelectric performance is challenging. In this work we show that thermoelectric performance of PEDOT:PSS can be enhanced by greatly improving its electrical conductivity in contrast to inorganic thermoelectric materials. Free-standing flexible and smooth PEDOT:PSS bulky papers were prepared using vacuum-assisted filtration. The electrical conductivity was enhanced to 640, 800, 1300, and 1900 S cm-1 by treating PEDOT:PSS with ethylene glycol, polyethylene glycol, methanol, and formic acid, respectively. The Seebeck coefficient did not show significant variation with the tremendous conductivity enhancement being 21.4 and 20.6 μV K-1 for ethylene glycol- and formic acid-treated papers, respectively. This is because secondary dopants, which increase electrical conductivity, do not change oxidation level of PEDOT. A maximum power factor of 80.6 μW m-1 K-2 was shown for formic acid-treated samples, while it was only 29.3 μW m-1 K-2 for ethylene glycol treatment. Coupled with intrinsically low thermal conductivity of PEDOT:PSS, ZT 0.32 was measured at room temperature using Harman method. We investigated the reasons behind the greatly enhanced thermoelectric performance.
AB - For inorganic thermoelectric materials, Seebeck coefficient and electrical conductivity are interdependent, and hence optimization of thermoelectric performance is challenging. In this work we show that thermoelectric performance of PEDOT:PSS can be enhanced by greatly improving its electrical conductivity in contrast to inorganic thermoelectric materials. Free-standing flexible and smooth PEDOT:PSS bulky papers were prepared using vacuum-assisted filtration. The electrical conductivity was enhanced to 640, 800, 1300, and 1900 S cm-1 by treating PEDOT:PSS with ethylene glycol, polyethylene glycol, methanol, and formic acid, respectively. The Seebeck coefficient did not show significant variation with the tremendous conductivity enhancement being 21.4 and 20.6 μV K-1 for ethylene glycol- and formic acid-treated papers, respectively. This is because secondary dopants, which increase electrical conductivity, do not change oxidation level of PEDOT. A maximum power factor of 80.6 μW m-1 K-2 was shown for formic acid-treated samples, while it was only 29.3 μW m-1 K-2 for ethylene glycol treatment. Coupled with intrinsically low thermal conductivity of PEDOT:PSS, ZT 0.32 was measured at room temperature using Harman method. We investigated the reasons behind the greatly enhanced thermoelectric performance.
KW - PEDOT:PSS
KW - Seebeck coefficient
KW - conductive polymer
KW - conductivity enhancement
KW - flexible thermoelectrics
KW - power factor
UR - http://www.scopus.com/inward/record.url?scp=84921266962&partnerID=8YFLogxK
U2 - 10.1021/am507032e
DO - 10.1021/am507032e
M3 - Article
AN - SCOPUS:84921266962
SN - 1944-8244
VL - 7
SP - 94
EP - 100
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 1
ER -