Baghdadi Neazar, Zoromba M Sh, Abdel-Aziz M H, Al-Hossainy A F, Bassyouni M, Salah Numan
Center of Nanotechnology, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Department of Chemical and Materials Engineering, King Abdulaziz University, Rabigh 21911, Saudi Arabia.
Polymers (Basel). 2021 Jan 16;13(2):278. doi: 10.3390/polym13020278.
Conducting polymers have attracted significant attention due to their easy fabrication, morphology modification, and their electrical properties. Amongst them, polypyrrole (PPy) has attractive thermoelectric (TE) properties. Engineering of this polymer in one-dimensional (1D) nanostructured form is found to enhance its TE performance. This was achieved in the present work by using multi-walled carbon nanotubes (MWCNTs) as a core template to direct the self-assembly of PPy and also to further enhance its TE performance. The growth of PPy on the sidewalls of MWCNTs was performed in an acidic medium based oxidative in situ polymerization. Various concentrations of MWCNTs within the range 1.1-14.6 wt.% were used to form the MWCNTs/PPy nanocomposites in 1D core-shell structures. The morphology and microstructure results of the produced nanocomposite samples showed that this MWCNTs were successfully coated by thick and thin layers of PPy. At low concentrations of MWCNTs, thick layers of PPy are formed. While at high concentrations thin layers are coated. The formed 1D nanocomposites have enhanced TE performance, particularly those containing higher contents of MWCNTs. The power factor and figure of merit values for the formed 1D nanocomposites recorded around 0.77 µV/mK and 1 × 10 at room temperature (RT), respectively. This enhancement was attributed to the perfect coating and good interaction between PPy and MWCNT through π-π stacking between the polymer chains and these nanotubes. These results might be useful for developing future TE materials and devices.
导电聚合物因其易于制备、形态可修饰及其电学性能而备受关注。其中，聚吡咯（PPy）具有吸引人的热电（TE）性能。发现将这种聚合物加工成一维（1D）纳米结构形式可提高其TE性能。在本工作中，通过使用多壁碳纳米管（MWCNTs）作为核心模板来引导PPy的自组装，并进一步提高其TE性能，实现了这一点。PPy在MWCNTs侧壁上的生长是在酸性介质中通过氧化原位聚合进行的。使用1.1 - 14.6 wt.%范围内的各种浓度的MWCNTs来形成一维核壳结构的MWCNTs/PPy纳米复合材料。所制备的纳米复合材料样品的形态和微观结构结果表明，MWCNTs成功地被PPy的厚层和薄层包覆。在低浓度的MWCNTs下，形成PPy的厚层。而在高浓度下则包覆薄层。所形成的一维纳米复合材料具有增强的TE性能，特别是那些含有较高含量MWCNTs的复合材料。所形成的一维纳米复合材料在室温（RT）下的功率因子和优值分别记录在约0.77 μV/mK和1×10左右。这种增强归因于聚合物链与这些纳米管之间通过π - π堆积实现的PPy与MWCNT之间的完美包覆和良好相互作用。这些结果可能对未来TE材料和器件的开发有用。
