Effect of Nonionic Conjugated Matrix Polymer and P-Dopant on Carbon Nanotube Aggregation and Thermoelectric Properties

MRS Advances ◽  
2018 ◽  
Vol 3 (60) ◽  
pp. 3483-3487
Author(s):  
Hui Li ◽  
Jiyuan Huang ◽  
Toshiyuki Sato ◽  
Paul Czubarow ◽  
Howard E. Katz
Keyword(s):  
Carbon Nanotube ◽  
Methyl Methacrylate ◽  
Optical Microscopy ◽  
Polymer Composite ◽  
Thermoelectric Properties ◽  
Electronic Conductivity ◽  
Conductivity Measurements ◽  
Matrix Polymer ◽  
Seebeck Coefficients ◽  
Comparable Concentration

ABSTRACTThe properties of a mixed metallic and semiconducting carbon nanotube (CNT) sample dispersed in nonconjugated poly(methyl methacrylate) (PMMA) and conjugated poly(bisdodecylquaterthiophene) (PQT12) were compared, with and without p-doping by NOBF4. The CNTs were distributed much more evenly, and percolated at much lower concentrations (ca. 2%), in the PMMA as compared to PQT12, as judged by optical microscopy and electronic conductivity measurements. Seebeck coefficients (S) obtained on the PMMA samples indicated dominance by the metallic fraction, with values <10 µV/K. Composites made with PQT12 alone showed slightly higher values of S, but with the addition of 3 wt % dopant, S increased markedly to about 100 µV/K at 5-10% CNT fractions, while conductivity was unexpectedly low. As the CNT fraction in the doped sample was increased to 25-30%, conductivity approached that of the comparable concentration of CNTs in PMMA, while S, ca. 15 µV/K, was still higher than that measured in PMMA. The observations inform interpretations of CNT-polymer composite thermoelectric data, pointing out the roles of conjugated main chains and added dopants in modulating contributions of CNTs to thermoelectric composite performance.

scholarly journals Enhanced thermoelectric properties exhibited by unreduced freestanding graphene oxide/carbon nanotube membranes

2021 ◽  
Author(s):  
Md. Saidul Islam ◽  
Hitomi Ohmagari ◽  
Mohammad Atiqur Rahman ◽  
Masahiro Fukuda ◽  
Yuta Shudo ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Carbon Nanotube ◽  
Thermoelectric Power ◽  
Thermoelectric Properties ◽  
Single Wall Carbon Nanotube ◽  
Single Wall Carbon ◽  
Seebeck Coefficients ◽  
Nanotube Membranes ◽  
Carbon Nanotube Membranes

Herein we determine the Seebeck coefficients, electric conductivities, and thermoelectric power factors of a range of unreduced graphene oxide (GO)/single-wall carbon nanotube (CNT) membranes incorporating different GO/CNT ratios as well...

scholarly journals Thermoelectric Properties of ZnSb Films Grown by MOCVD

1997 ◽  
Vol 478 ◽  
Author(s):  
R. Venkatasubramanian ◽  
E. Watko ◽  
T. Colpitts
Keyword(s):  
Thermoelectric Properties ◽  
Growth Parameters ◽  
Chemical Vapor ◽  
Growth Conditions ◽  
Free Carrier ◽  
Conductivity Measurements ◽  
Seebeck Coefficients ◽  
Short Annealing ◽  
P Type ◽  
Concentration Levels

AbstractThe thermoelectric properties of ZnSb films grown by metallorganic chemical vapor deposition (MOCVD) are reported. The growth conditions necessary to obtain stoichiometric ZnSb films and the effects of various growth parameters on the electrical conductivity and Seebeck coefficients of the films are described. The as-grown ZnSb films are p-type. It was observed that the thicker ZnSb films offer improved carrier mobilities and lower free-carrier concentration levels. The Seebeck coefficient of ZnSb films was found to rise rapidly at approximately 160°C. The thicker films, due to the lower doping levels, indicate higher Seebeck coefficients between 25 to 200°C. A short annealing of the ZnSb film at temperatures of ˜ 200°C results in reduced free-carrier level. Thermal conductivity measurements of ZnSb films using the 3-ω method are also presented.

Structure and Thermoelectric Properties of New Quaternary Tin and Lead Bismuth Selenides, K1+xM4-2xBi7+xSe15 (M = Sn, Pb) and K1+xSn5-xBi11+xSe22

2000 ◽  
Vol 626 ◽  
Author(s):  
Antje Mrotzek ◽  
Kyoung-Shin Choi ◽  
Duck-Young Chung ◽  
Melissa A. Lane ◽  
John R. Ireland ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Single Crystal ◽  
Thermoelectric Properties ◽  
Three Dimensional ◽  
Structure Type ◽  
Narrow Gap ◽  
Low Thermal Conductivity ◽  
Seebeck Coefficients ◽  
Metal Atoms ◽  
Anionic Framework

ABSTRACTWe present the structure and thermoelectric properties of the new quaternary selenides K1+xM4–2xBi7+xSe15 (M = Sn, Pb) and K1-xSn5-xBi11+xSe22. The compounds K1+xM4-2xBi7+xSe15 (M= Sn, Pb) crystallize isostructural to A1+xPb4-2xSb7+xSe15 with A = K, Rb, while K1-xSn5-xBi11+xSe22 reveals a new structure type. In both structure types fragments of the Bi2Te3-type and the NaCl-type are connected to a three-dimensional anionic framework with K+ ions filled tunnels. The two structures vary by the size of the NaCl-type rods and are closely related to β-K2Bi8Se13 and K2.5Bi8.5Se14. The thermoelectric properties of K1+xM4-2xBi7+xSe15 (M = Sn, Pb) and K1-xSn5-xBi11+xSe22 were explored on single crystal and ingot samples. These compounds are narrow gap semiconductors and show n-type behavior with moderate Seebeck coefficients. They have very low thermal conductivity due to an extensive disorder of the metal atoms and possible “rattling” K+ ions.

Bioinspired neuromorphic module based on carbon nanotube/C60/polymer composite

2015 ◽  
Vol 49 (15) ◽  
pp. 1809-1822 ◽  
Author(s):  
Kyunghyun Kim ◽  
Andrew Tudor ◽  
Chia-Ling Chen ◽  
Dongwon Lee ◽  
Alex M Shen ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Polymer Composite

Study on Phases and Thermoelectric Properties of Bulk Fe4Sb12 and Fe3CoSb12 Prepared by Milling and Sintering

2011 ◽  
Vol 121-126 ◽  
pp. 1526-1529
Author(s):  
Ke Gao Liu ◽  
Jing Li
Keyword(s):  
Thermoelectric Properties ◽  
Impurity Phase ◽  
Semiconductor Materials ◽  
Thermal Constant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Seebeck Coefficients ◽  
Maximum Value ◽  
Type Semiconductor ◽  
P Type

Bulk Fe4Sb12 and Fe3CoSb12 were prepared by sintering at 600 °C. The phases of samples were analyzed by X-ray diffraction and their thermoelectric properties were tested by electric constant instrument and laser thermal constant instrument. Experimental results show that, the major phases of bulk samples are skutterudite with impurity phase FeSb2. The electric resistivities of the samples increase with temperature rising at 100~500 °C. The bulk samples are P-type semiconductor materials. The Seebeck coefficients of the bulk Fe4Sb12 are higher than those of bulk Fe3CoSb12 samples at 100~200 °C but lower at 300~500 °C. The power factor of the bulk Fe4Sb12 samples decreases with temperature rising while that of bulk Fe3CoSb12 samples increases with temperature rising at 100~500 °C. The thermal conductivities of the bulk Fe4Sb12 samples are relatively higher than those of and Fe3CoSb12, which maximum value is up to 0.0974 Wm-1K-1. The ZT value of bulk Fe3CoSb12 increases with temperature rising at 100~500 °C, the maximum value is up to 0.031.The ZT values of the bulk Fe4Sb12 samples are higher than those of bulk Fe3CoSb12 at 100~300 °C while lower at 400~500 °C.

Sign in / Sign up

Export Citation Format

Share Document