Exploration Of Preparation And Properties Of One-dimensional Composite Thermoelectric Materials

In recent years,the intensification of energy and environmental crises has made the research and development of environmental protection and green materials more meaningful.Thermoelectric materials are increasingly attracted the attention of researchers due to their ability to convert electricity and heat energy directly.The main content of this work includes exploring the preparation of one-dimensional composite thermoelectric materials and optimizing the thermoelectric properties of the materials.It is aimed at the supplement for the study and innovation of one-dimensional thermoelectric materials.The specific work is as follows:1.PEDOT:p-TSA/glass fiber thermoelectric materials were prepared using in situ polymerization.The effects of different concentrations of oxidant,dopant mass fraction,and post-treatment on the thermoelectric properties of the material were explored,and the optimal synthesis conditions under the factors investigated in this experiment were obtained.At room temperature,the maximum conductivity and Seebeck coefficient of the pure 3,4-ethylenedioxythiophene:p-toluenesulfonic acid/glass fiber material were 169 Sm-1 and 32.1 ?VK-1,respectively.So the maximum power factor obtained was 0.121 ?Wm-1K-2.When the oxidant concentration is the same,the thermoelectric properties of materials with low doping fractions are generally higher than those with high doping fractions.Post-treatment with methanol optimized the thermoelectric properties of the material.The maximum conductivity and Seebeck coefficients were 3184 Sm-1 and 48.5?VK-1,respectively.When the mass fraction of p-toluenesulfonic acid relative to EDOT was 76%and the concentration of ammonium persulfate was 11 mmolL-1,the thermoelectric performance was the best.The optimized power factor was 6.74 ?Wm-1K-2,which is about 56 times larger than that of the pure sample.The thermoelectric properties of the materials were effected on the degree of conjugation and ordering of the polymer chains.In addition,a preliminary explanation of the transport mechanism of carriers was given in this work.2.Polypyrrole/glass fiber thermoelectric materials were prepared by in situ polymerization.The effects of different oxidant concentrations and pre-treatment on thermoelectric properties were explored.The maximum Seebeck coefficient of the original polypyrrole/glass fiber without pretreatment at room temperature was 9.9 ?VK-1.After the pre-treatment of glass fiber,the conductivity increased to 13.5 Sm-i,the Seebeck coefficient decreased slightly,and the value was 6 ?VK-1.The maximum power factor calculated was 486×10-6 ?Wm-1K-2.Pre-treatment was an effective method to increase the force between the substrate and the coating in the polypyrrole/glass fiber material,therefore the thermoelectric performance was enhanced.