Thermoelectric properties of nanocomposite thin films prepared with poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) and graphene.

Carbon nanotubes (CNTs), either single wall carbon nanotubes (SWNTs) or multiwall carbon nanotubes (MWNTs), can improve the thermoelectric properties of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT : PSS), but it requires addition of 30-40 wt% CNTs. We report that the figure of merit (ZT) value of PEDOT : PSS thin film for thermoelectric property is increased about 10 times by incorporating 2 wt% of graphene. PEDOT : PSS thin films containing 1, 2, 3 wt% graphene are prepared by solution spin coating method. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy analyses identified the strong π-π interactions which facilitated the dispersion between graphene and PEDOT : PSS. The uniformly distributed graphene increased the interfacial area by 2-10 times as compared with CNT based on the same weight. The power factor and ZT value of PEDOT : PSS thin film containing 2 wt% graphene was 11.09 μW mK(-2) and 2.1 × 10(-2), respectively. This enhancement arises from the facilitated carrier transfer between PEDOT : PSS and graphene as well as the high electron mobility of graphene (200,000 cm(2) V(-1) s(-1)). Furthermore the porous structure of the thin film decreases the thermal conductivity resulting in a high ZT value, which is higher by 20% than that for a PEDOT : PSS thin film containing 35 wt% SWNTs.

[1]  Yang Yang,et al.  On the mechanism of conductivity enhancement in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film through solvent treatment , 2004 .

[2]  K. Y. Wong,et al.  Effects of a base coating used for electropolymerization of poly(3,4-ethylenedioxythiophene) on indium tin oxide electrode , 2006 .

[3]  Arthur J. Epstein,et al.  Secondary doping in polyaniline , 1995 .

[4]  G. Papavassiliou,et al.  Thermoelectric figure of merit of ττ-(EDO-S,S-DMEDT-TTF)2(AuBr2)1+y, (y≤0.875y≤0.875) and (TMTSF)2PF6 , 2009 .

[5]  Andre K. Geim,et al.  The rise of graphene. , 2007, Nature materials.

[6]  Wenqing Zhang,et al.  Enhanced thermoelectric performance of single-walled carbon nanotubes/polyaniline hybrid nanocomposites. , 2010, ACS nano.

[7]  J. Kysar,et al.  Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene , 2008, Science.

[8]  Ju Hyun Park,et al.  Stable aqueous dispersion of reduced graphene nanosheets via non-covalent functionalization with conducting polymers and application in transparent electrodes. , 2011, Langmuir : the ACS journal of surfaces and colloids.

[9]  H. J. Kim,et al.  Conductivity enhancement in single-walled carbon nanotube bundles doped with K and Br , 1997, Nature.

[10]  Qin Yao,et al.  The High Thermoelectric Properties of Conducting Polyaniline with Special Submicron-fibre Structure , 2005 .

[11]  P. Pickup,et al.  Chemical Synthesis, Characterization, and Electrochemical Studies of Poly(3,4-ethylenedioxythiophene)/Poly(styrene-4-sulfonate) Composites , 1999 .

[12]  H. Yan,et al.  Stretched polyaniline films doped by (±)-10-camphorsulfonic acid : Anisotropy and improvement of thermoelectric properties , 2001 .

[13]  G. Fudenberg,et al.  Ultrahigh electron mobility in suspended graphene , 2008, 0802.2389.

[14]  M. Dresselhaus,et al.  Recent developments in thermoelectric materials , 2003 .

[15]  R. Colman,et al.  Comparisons between Haydeeite, α-Cu3Mg(OD)6Cl2, and Kapellasite, α-Cu3Zn(OD)6Cl2, Isostructural S = 1/2 Kagome Magnets , 2010 .

[16]  K. Koumoto,et al.  Electrical and Optical Properties of Radio-Frequency-Sputtered Thin Films of (ZnO)5In2O3 , 1998 .

[17]  Yuyan Shao,et al.  Graphene Based Electrochemical Sensors and Biosensors: A Review , 2010 .

[18]  Peter Andersson,et al.  The Origin of the High Conductivity of Poly(3,4-ethylenedioxythiophene)−Poly(styrenesulfonate) (PEDOT−PSS) Plastic Electrodes , 2006 .

[19]  H. Tan,et al.  Covalent bonded polymer–graphene nanocomposites , 2010 .

[20]  A. Halliday,et al.  Core formation on Mars and differentiated asteroids , 1997, Nature.

[21]  Lidong Chen,et al.  Thermoelectrics: Direct Solar Thermal Energy Conversion , 2008 .

[22]  Peng Wei,et al.  Anomalous thermoelectric transport of Dirac particles in graphene. , 2008, Physical review letters.

[23]  Wha-Tzong Whang,et al.  High-conductivity poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film for use in ITO-free polymer solar cells , 2008 .

[24]  J. Schlenoff,et al.  Correlation of Seebeck coefficient and electric conductivity in polyaniline and polypyrrole , 1998 .

[25]  Li Shi,et al.  Two-Dimensional Phonon Transport in Supported Graphene , 2010, Science.

[26]  M. Cutler,et al.  Electronic Transport in High-Resistivity Cerium Sulfide , 1964 .

[27]  Choongho Yu,et al.  Improved thermoelectric behavior of nanotube-filled polymer composites with poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate). , 2010, ACS nano.

[28]  C. N. Lau,et al.  Superior thermal conductivity of single-layer graphene. , 2008, Nano letters.

[29]  Andreas Hirsch,et al.  Doping of single-walled carbon nanotube bundles by Brønsted acids , 2003 .

[30]  G. J. Snyder,et al.  Complex thermoelectric materials. , 2008, Nature materials.

[31]  Klaus Müllen,et al.  Composites of Graphene with Large Aromatic Molecules , 2009 .

[32]  S. Woo,et al.  Electrochemical oxygen reduction on nitrogen doped graphene sheets in acid media , 2010 .

[33]  F. Chen,et al.  High‐Conductivity Poly(3,4‐ethylenedioxythiophene):Poly(styrene sulfonate) Film and Its Application in Polymer Optoelectronic Devices , 2005 .

[34]  H. Dai,et al.  Highly conducting graphene sheets and Langmuir-Blodgett films. , 2008, Nature nanotechnology.

[35]  P. Kim,et al.  Thermoelectric and magnetothermoelectric transport measurements of graphene. , 2008, Physical review letters.

[36]  Yang Yang,et al.  A one-step, solvothermal reduction method for producing reduced graphene oxide dispersions in organic solvents. , 2010, ACS nano.

[37]  Andre K. Geim,et al.  Electric Field Effect in Atomically Thin Carbon Films , 2004, Science.

[38]  G. Lisensky,et al.  Thermoelectric Devices: Solid-State Refrigerators and Electrical Generators in the Classroom , 1996 .