Preparation And Thermoelectric Properties Of Polyaniline/carbon Nanofibers Composite Films

Polyaniline become a promising organic thermoelectric materials because of its special structure?easy preparation and unique doping/de doping properties.However,the electrical conductivity and Seebeck coefficient of PANI are poor.In this paper,the effects of different oxidant ratios on the thermoelectric properties of polyaniline films were investigated by controlling the feeding ratio of APS and Ani;1 D CNFs was used to prepare organic/inorganic nanocomposites and their thermoelectric performance were studied.A series of polyaniline with different degree of oxidation were prepared by changing the molar ratio of APS/Ani by chemical oxidation.The films were prepared by solution casting method,and the thermoelectric properties were investigated.The best thermoelectric properties 228 S cm-1 were obtained when the feeding ratio of APS/Ani is 1;CNFs/PANIwas prepared by physical stirring and sonicating,TEM characterization shows that CNFs and PANI were simply lapped together and the distribution of CNFs in PANI is not uniform,consequently the electrical conductivity of CNFs/PANI decreased a lot,the thermoelectric performance is less than pure PANI film;PANI@CNFs was prepared by in situ polymerization,the results show that the thermoelectric properties of PANI can improve a lot by in-situ polymerization than directly mixing.Aniline monomer can be absorbed to the surface of CNFs due to the functional group of CNFs.This affected the polymerization of PANI,leading the growth of PANI along the axis of CNFs,so that the surface morphology of CNFs covered by CNFs is better and the self-polymerized PANI is also less.A maximum electrical conductivity 395 S cm-1of PANI@CNFs was obtained when the CNFs weight fraction reaches 19%,and the tensile strength of the film is as high as 13.6 ± 0.68 Mpa.